Construction Department of the Heilongjiang Province

Design Manual for energy efficient and comfortable rural houses

Heilongjiang China

Abstract

Preamble...... 6 Introduction...... 7

Chapter 1 Essential of heat transfer and comfort in rural houses...... 9

1.1- Introduction...... 9 1.2- Main heat transfers in a rural house...... 9 1.3- Parameters of heat transfers in a rural house...... 11 1.4 - Thermal comfort in a rural house...... 13

Chapter 2 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ...... 14

2.1 - For a global approach...... 14 2.2 - Designing an energy efficient layout of the house...... 14 2.3 - Designing and implementing opaque building envelope components ...... 16 2.4 - Designing and implementing energy efficient windows...... 30 2.5 - Avoiding thermal bridges...... 34 2.6 - Infiltration and ventilation...... 37

Chapter 3 Achievment of a very low energy consumption house...... 39

5 Preamble

nergy growing demand, global warming and the environmental deterioration have stressed that combating the greenhouse effect and climate change require heightened dialogue and cooperation between all countries. France through Ethe “Grenelle Environment Forum”, which aims at dividing by 4 greenhouse gas emissions by 2050, and China through the “ National Climate Change Programme”, both recognize energy management as a key factor. They have targeted ambitious goals to improve energy efficiency in all economic sectors, with a special attention to construction. Supported by the French Ministry in charge of Energy, Environment, Sustainable Development and Spatial Planning (MEEDDAT), under the funding of the French Global Environment Facility (FGEF), a joint cooperation programme has been developed since 1999 involving the Chinese Ministry of Housing and Urban-Rural Development (MoHURD), the provincial Construction Commissions and municipal authorities.

This programme, coordinated by the French Agency for Environment and Energy Management (ADEME), has successfully demonstrated in a first phase a reduction of 50% of energy consumption in cold areas with a construction overcost of 7% in new urban buildings. It has been focused in particular in Heilongjiang province, where severe winter temperatures create significant heating needs. In a second phase, the programme was extended to rural housing, in Daqing and Heihe districts, by the construction of energy efficient pilot rural houses.

As China is holding the global highest construction rate in the world, with more than half the population living in rural areas, the generalization of such pilot projects will bring significant progress to reduce energy consumption and improve comfort at the same time. To disseminate these innovative construction practices, a guide book has been elaborated, with the support of ADEME.

The present “Design manual of comfortable and energy efficient rural houses in Heilongjiang province of China” has the objective to bring a contribution for helping out provincial and local authorities, construction teams, farmers and their families to tackle those social, economical and environmental issues of rural housing construction, both in Heilongjiang and in the other Northern Provinces of China.

It provides inputs to make more comfortable houses both in terms of inside temperature and air quality. It gives detailed indications for designing each component of the house (roof, walls, windows, floors, ventilation, heating systems...) with energy efficiency standards allowing to reduce coal expenses with minimal impact on construction costs.

Consequently, the implementation of such energy efficient designs will contribute to divide by 2 the yearly combustible consumption and thereby to avoid the release of about 5 tons of CO2 in the atmosphere per rural house, thus contributing significantly to reduce greenhouse gas emissions.

This guide book proposes practical solutions and covers energy efficiency building design technologies available in Nor- thern China, where it has already triggered the construction of 1 300 new energy efficient houses.

We sincerely hope this work, accomplished with joint expertise of Chinese and French specialists, will bring a contribution to rural harmonious development, quality of life and environmental protection in remote areas of Heilongjiang.

We are pleased to have participated to this cooperative work and we hope to continue our long time partnership with the Construction Department of the Heilongjiang Province of the People’s Republic of China for sustainable development achievement.

Dominique Campana Director of the International Affaires Division ADEME

6 Introduction

eilongjiang province is located on the most northern part of China. It has a continental cold climate with four clearly distinct seasons. It also has a vast territory and very rich Hproducts. Human activities in Heilongjiang province can be dated back to 50 000 years ago, so it has a long history and culture. Heilongjiang province, also a traditional agricultural province, has almost half of its population engaged in agriculture, amounting to most of the provincial economy. Due to its particular geographical conditions, the early inhabitants in Heilongjiang province lived on farming and hunting. Their habitats were mainly built with local and natural materials, such as wood, straw and mud. People used original ways and smart ideas to make their homes comfortable, warm and also environmental friendly. At that time, the typical houses, such as “Diyinzi”(1), “Mukeleng”(2) and “Gandalei”(3), were ideally energy efficient, as has been recorded in history. In the last century, rural houses have been changed to brick-tile-houses, which represented modern civilization and could also meet the growing needs of housing. But people kept on seeking an appropriate way to make their houses energy efficient and comfortable. After the reform and opening up, especially the movement of new country construction, along with the growth of economy and the demand for energy savings and carbon emission reductions, the Heilongjiang province makes great efforts to reduce the energy consumption of newly built houses. We carried on several projects, such as “Double Hundred-Thousand” and “Comfortable Home”, to improve living conditions and to motivate farmers’ involvement, in order to spark off the development of rural housing construction. At the same time, government also brings in the advanced experiences and techniques from other countries. We also guide farmers to use local materials and new energy saving technology in building their houses. The Heilongjiang province has a huge potential to reduce energy consumption, due to the great amount of houses, comprising about 4 400 millions square meters of existing houses and nearly 9 millions square meters of new houses each year. If half of these houses had been built or refur- bished as energy saving houses, there would be a reduction of 10 million tons in coal consumption during one heating season. In consequence, not only the living condition of farmers can be totally improved, it will also make a great contribution to provincial, national, even global reduction of energy consumption and carbon emission. French and Chinese governments have been cooperating for 10 years in energy saving aspects. During this period, we have made successful progress in several projects carried on in the cities of Harbin, Daqing and Heihe. In order to popularize our remarkable results, ADEME and the Heilongjiang Provincial Government as well as the Construction Department decided to make the “Design manual of comfortable and energy efficient rural houses in Heilongjiang province of China”.

(1) A simply house made by straw and mud. (2) A simply house in the shape of semi-basement. (3) A typical house made by timber crib.

7 Design manual for energy efficient and comfortable rural houses in HLJ

This manual concludes not only a successful experience in the construction of energy saving houses, but also contains new ideas and techniques brought by French experts. These techniques include very detailed design of structures, studies and strategies of natural ventilation, as well as insulation of the heat bridges. This manual demonstrates the best technology, fulfils the wise and hard work of experts of both countries, and also represents the sincere friendship of French and Chinese governments. This manual is simple and easy to learn. It has great value to guide the farmers on how to build their new houses. I believe this book will be widespread and well-liked by farmers as a good present. We will pay great attention to the popularization and utilization of this book, and give it to farmers as soon as possible. We also intend to widely recommend it as new building techniques and standards. Finally, I would express my heartfelt thanks to ADEME as well as the French officers and experts. Meanwhile, I also expect another cooperation between our two governments for the energy saving and improvement of farmers’ living conditions. I hope we can do a significant contribution to the environmental protection of our common home — the earth.

July 1st 2008

SHI Dianchen Director of Construction Department of the Heilongjiang Province

The FGEF programme in China

Between 1999 and 2009, France and China undertook a major cooperative project focusing on the issues of energy efficiency and sustainable development in the construction and rehabilitation of housing. The programme was endowed with a total budget of 6 million euros financed by the French Global Environment Facility (FGEF). The aid was primarily provided in the form of consulting and engineering services which facilitated access to new technologies. The programme, which applied to projects already decided on and financed at local level, made it possible to introduce measures designed to improve the energy efficiency of new and existing housing while requiring only low additional costs at a level acceptable for the local market (less than 7% of the additional cost relating to the construction of social housing and 18% relating to rural houses). Activities were concentrated in Shanghai, a city which has both heating and air conditioning requirements, as well as in two provinces and one municipality in the North where the very low winter temperatures result in significant heating requirements: Heilongjiang, Liaoning and Beijing. To date, 870,000 m2 of energy-efficient housing have been constructed and 29,000 m2 have been rehabilitated, thus reducing CO2 emissions by more than 50,000 tonnes every year. Special attention was paid to the construction of housing in rural environments since this sector represents more than 50% of construction work in China. The programme also included the construction of 24 rural pilot houses in a number of villages in Heilongjiang (in Shengli and the Heihe region). Methods which can be replicated at both the economic and technical levels were introduced in order to achieve the objective of a 50% saving in energy consumption for heating and to improve the comfort of inhabitants. This guide indicates the methods used, while also helping spread awareness of the concept of energy efficiency in the construction of rural houses in regions exposed to extreme winter climates.

8 Essential of heat transfer and comfort in rural houses

Chapter 1 Essential of heat transfer and comfort in rural houses

1.1- Introduction 1.2.2- Heat losses The heat losses consist of the conduction (and radia- In order to be able to design and build better rural hou- tion) heat losses and the convective heat losses: ses both in terms of energy effi ciency and comfort, it is • Conduction heat losses through the building en- essential to have a good understanding: velope whether they are opaque components (roof, • On a global scale, of what are the main heat transfers walls, fl oor, door) or transparent components (win- phenomena in a house and how these heat transfers dows and other glazed surfaces); occur ; • Convective heat losses which are due to cold air • On a more detailed scale, what are the main parame- infi ltration and ventilation through the houses. These ters driving these heat phenomena. cold and fresh air infi ltrations : • Mostly occur through windows and door cracks (and even sometimes through wall cracks if they are 1.2 - Main heat transfers not well sealed and mortared), through door openings in a rural house when people move in and out, through chimney and, in some buildings, through specifi c forced ventilation 1.2.1- Overall perspective systems ; Main heat transfers occurring in a rural house during • Are necessary for health purposes in order to al- heating season low people to breath and evacuate internal pollutants

Through chimney

Through roof Through roof

Through door Through windows By electrical Through walls equipment By person Through walls Conduction heat losses Through fl oor External heat gains Solar radiation Convective heat losses Internal heat gains

9 Design manual for energy efficient and comfortable rural houses in HLJ

(moisture, smoke, odors, ...) and to allow combustion electrical equipments like lighting, appliances, etc … of stove and boilers…; Such heat gains contribute to the heating of the house • But should not be too high in terms of volumetric and lower the energy consumption of the heating sys- flow rates because they bring a lot of cold inside the tems and this is why they are called “free heat gains”. houses, thus decreasing comfort and increasing hea- This contribution can be extremely significant in a well ting expenses. designed energy efficiency house.

Conductive heat losses through roof, walls and floor So called “passive solar houses” is a category of energy efficient houses making large use of very energy efficient windows and other solar collection technologies to minimize the use of conventional fuel for heating. This contribution to heat balance in a house is not negligible even in a conventional poorly insulated house because winter solar radiation availability is high in Heilongjiang and because rural architecture usually makes good use of passive solar collection by designing houses with South orientation and using large windows to the South. Conductive and convective heat losses through windows and door

1.2.3- Heat gains 1.2.4- Heat balance and heating needs The heat gains are from the exterior the interior: Once these basic principles are set, it is easy to un- • External heat gains due to solar radiation energy en- derstand that heating needs of a house that will have tering the house through windows and glazing and also, to be supplied by various heating systems (khang, to a smaller extent, through opaque surfaces like walls boiler,…) making use of various fuels (agricultural re- and roof (in fact solar gains through opaque building sur- sidues, coal, …) will be, for every day of the heating faces contribute to slightly reduce heat losses through season the difference between heat losses and free such surfaces). These solar heat gains are called pas- heat gains: sive solar gains. Obviously the closer to the South the windows are, the more passive solar heat gain they will bring inside the house ; heat needs = • Internal or indoor heat gains due to occupants (each heat losses – (solar gains + indoor gains) adult person sitting still releases an average heat power of about 100 W) and heat released in the building by The heating consumption of a house will be:

house heating consumption = heat needs / global heating system efficiency

One will never stress enough the basic fact that energy efficient house design consists in working si- multaneously in the following directions: - Reducing heat losses; - Optimizing components affecting heat gains; - Optimizing the energy efficiency of the various heating systems.

10 Essential of heat transfer and comfort in rural houses

1.3- Parameters of heat transfers in a rural house

We give here after the comparative calculation out- put of theoretical heating energy consumption for two rural houses located in Heihe area:

1- The first one is a conventional brick house with fairly poor insulation, even though much better than many traditionnal rural mud brick houses: • Double brick wall The theoretical coal consumption of the conventional • No floor insulation house is huge (close to 11 t / year). • Roof insulation with saw dust or wood chips above This is a theoretical calculation supposing that all rooms ceiling of this house are heated throughout the winter at a tem- • Double glazing wooden windows perature of 18°C. • Average air tightness Real houses do not consume that huge amount of coal because farmers cannot afford to heat all rooms simul- taneously and to maintain such comfort temperatures in their homes: for many of them their whole yearly income would barely be sufficient to buy the coal they would need. However the difference between such theoretical “energy consumptions for comfort” that would bring up the comfort level of farmers to the same level as other Chinese citizens experience in urban apartments with subsidized heating expenses on one hand, and the actual consumption of farmers (a few tons of coal per year) on the other hand, illustrate in a concrete way the poor comfort conditions that farmers experience. The lack of basic comfort is the price they pay for living in houses with poor design in terms of energy efficiency 2- The second one is a well insulated house and with no financial means for paying high energy similar to the most insulated house achieved costs. through the Sino-French pilot project in Heihe:

• 18 cm EPS insulation in walls • 12 cm EPS insulation in floor • 18 cm EPS + 20 cm wood chips in the roof above the ceiling • triple glazing plastic windows + well ceiled night times curtains • improved air tightness with inlet pipes for fresh hygienic air

11 Design manual for energy efficient and comfortable rural houses in HLJ

Conventional brick house

Convective heat losses through AIR INFILTRATION: 1.12 tons of coal per year 11% Energy consumption: 10.60 tons of coal per year Conductive net heat losses through ROOF: 2.02 tons of coal per year 19%

Conductive net heat losses through WALLS: 4.64 tons of coal per year 44%

Conductive net heat losses through DOORS: 0.13 tons of coal per year 1%

Conductive net heat losses through FLOORS: 1.30 tons of coal per year 12%

Conductive net heat losses through WINDOWS: 1.39 tons of coal per year 13%

Well insulated house Convective heat losses through AIR INFILTRATION: 0.52 tons of coal per year 19% Energy consumption: 2.75 tons of coal per year Conductive net heat losses through ROOF: 0.45 tons of coal per year 16%

Conductive net heat losses through WALLS: 0.55 tons of coal per year 20%

Conductive net heat losses through DOORS: 0.10 tons of coal per year 4%

Conductive net heat losses through FLOORS: 0.44 tons of coal per year 16%

Conductive net heat losses through WINDOWS: 0.69 tons of coal per year 25%

12 Essential of heat transfer and comfort in rural houses

The calculations of heat losses, heat needs as well as ronmental protection, it is also essential to do so while heating consumption, make use of official standard bringing inhabitants optimal thermal comfort. Chinese calculation method. The main parameters that have a significant influence on The calorific value used in the calculation is the value winter comfort in a rural house are the following: of average coal really used in HLJ (5500 Wh /kg) and • Internal air temperature; not the reference theoretical value of anthracite coal • Inner building envelope temperature (walls, glazing, which is used in standards (8140 Wh /kg). roof, floor); The global heating system efficiency is supposed to • Mean radiant temperature, also called resultant tem- be 62%. perature, which is the temperature effectively felt by oc- One can see that increasing insulation and air ti- cupants and related with the two previous parameters; ghtness of the house including night time shutters on • Internal relative air humidity that should be kept be- windows can bring down theoretical heating needs low 60% for better comfort and for avoiding condensa- and consumption by a factor of nearly 4. tion and moisture appearance on inner walls; • Air streams on occupants with air colder than skin temperature ( about 32°C) that should be kept below 0.2 m/s; • Temperature gradient in the room (air temperature difference at various heights within the room) that should Energy consumption be kept minimal by preferring radiant heating systems of heating system rather than convective ones (see the follow chapter) Envelope insulation not only reduces heat consumption by lowering heat transfer through building envelope, it Conventional house also contributes to improve energy efficiency by giving Well insulated house better comfort with relatively lower air temperature because of positive effect on higher internal surfaces Once again the actual savings from one conventional temperatures. house to the energy efficient house could be different from the theoretical saving computed here above because: • Actual average heating temperatures in the house, especially the conventional house where they can be much lower than the ones assumed in calculations; • Actual heated surface area is often limited to one or two rooms which decreases ctual energy needs and consumption; • Very likely a large part of the theoretical energy savings of the energy efficient house would be “converted “to comfort improvement.

1.4- Thermal comfort in a rural house

If it is essential to minimize fuel uses in a house in order to reduce energy expenses and contribute to envi-

13 Design manual for energy efficient and comfortable rural houses in HLJ

Chapter 2 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

· A single house S1=312m² 2.1- For a global approach Shape coefficient S1/V=1.08 Designing and building energy efficient and comfortable rural houses is a global process that require step by step careful attention in which none of the parameters that can affect overall performance should be neglected from the global house layout in the design phase to the least thermal bridge in the very last · A dual row house S2=288m² stage of construction. Shape coefficient S2/V=1.00 This chapter introduces a concrete and practical step- by-step methodology to design and implement such better houses. 2.2- Designing an energy A row house, in central position S3=264m² efficient layout of the house Shape coefficient S3/V=0.92

2.2.1- Optimizing the shape coefficient The shape coefficient expresses the ratio of the overall outside envelope (walls, windows, doors, ceiling and floor) area of a house with respect to its volume.

Total envelope surface area S(m2) Shape coefficient = Total volume V(m3)

Thus the lower the shape coefficient the most energy Heat losses and thus heating consumptions are di- efficient the house will be. rectly proportional to these shape coefficients. Traditional rural houses of HLJ generally have a good If many units row houses are not possible at least shape coefficient. dual row houses should be built rather than inde- For a house of 12m (length) × 9m (width) × 3m (habi- pendent houses because shared separation walls table height), with different neighboring possibilities, between houses decreases heat losses, together the shape coefficient will be: with reducing substantially construction costs.

14 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

2.2.2- Optimal floor plan design

Small North windows

Buffer space

Toilet Kitchen

Storage

Khang Air lock

Bedroom Living room

Large South windows

Floor plan design is an essential step in energy effi- • Put rooms generating their own heat to the North of ciency design by optimizing the use of climatic para- the house: kitchen, boiler room, etc. meters to reduce heating needs of a house. • Put the living spaces to the South of the house The main steps of energy efficient and comfortable so they can benefit from free and comfortable solar floor design illustrated on the above drawing are the gains; following: • Design a protected entrance with an air lock to • Put buffer spaces like storage, unheated rooms prevent cold wind to enter when farmers and their preferably on the North side of the house to protect families walk in and out the houses; the living spaces from North cold winds and lower The basics of energy efficient floor plan design are temperatures; fairly well mastered by farmers of HLJ that have an excellent empirical experience of their climate.

15 Design manual for energy efficient and comfortable rural houses in HLJ

2.3- Designing and implementing opaque building envelope components 2.3.1.2- Design and sizing • Humidity protection 2.3.1- Floor Humidity protection of the house is essential and 2.3.1.1- Justification floors should be carefully designed and implemented Floor insulation is not conventional in HLJ rural hou- with respect to these potential hazards of capillary ses. However it is absolutely essential: humidity transfer through floor and up walls. • To drastically reduce heating consumptions: floor The following measures should be achieved prior to can represent up to 30% of total heat losses in a rural floor construction insulation: house if it is not insulated while other parts are par- • Implement appropriate perimeter drain work with tially insulated; rocks and gravel; • To drastically increase comfort for inhabitants be- • Implement a plastic vapor barrier under the house cause cold radiation surface at feet level induces high before floor insulation work (usually a polyethylene discomfort called the “cold feet syndrome”. sheet) .

The drain will be put at the foot of the foundation.

Implementation of a plastic vapor barrier before pouring concrete slab to avoid humidity.

16 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

• Heavy mass or wooden floors? ring walls, insulation work has to be done separately High thermal mass floors require more heating energy from one room to the other and one can also use va- to reach comfort temperature. rious finishing like: In addition conductive materials like concrete and ti- • Wooden floor for living room ad bedroom les will conduct heat from body and “feel” colder than • Concrete floor for kitchen, bathroom and entrance wood structures. This is why it is better to use wooden floors for better comfort. Insulation with appropriate thickness should be installed under floor surface whether it is wood or concrete. Since various parts of the floor are separated by bea-

Concrete floor Wooden floor

Insulating material Thickness : Advantages / drawbacks minimum & Ideal Comments Perlite 20 cm - 40cm Fairly cheap. Requires high thickness for reaching good insulating value. Expanded Polystyrene 10 cm - 20 cm Available even though fairly expensive. (EPS ) Uncompressible high density EPS should be used (greater than 25 kg / m3). Can be destroyed (eaten) by rodents. Extruded Polystyrene (XPS) 8 cm - 15 cm Very expensive but very efficient. Not always available. The best insulating option for floors with respect to energy efficiency.

17 Design manual for energy efficient and comfortable rural houses in HLJ

2.3.1.3- Implementation details

Concrete floor

Baseboard

Plaster board or cement render Tiling

Brick

Concrete floor

Wire-mesh grid

XPS insulation

PE sheet

Gravel

Compacted soil

Frost line

• When foundation work is finished a thin concrete between boards edges above plastic PE waterproo- slab allows to set a flat zero level for floor. Water- fing layer. PE sheets should be pulled up at floor pe- proofing can be achieved with implementing conti- rimeter and a band of insulation should be installed nuous polyethylene (PE) sheets, with absolutely no vertically against the exterior walls before pouring interruption throughout concrete slab surface, sealed concrete slab in order to guarantee waterproofing. by bitumen and by continuing under insulation edges Insulation should be continuous between horizontal (on cross section it can be an EPS or XPS board) The and vertical boards in order to avoid thermal bridge walls were cut by a tight barrier (bitumen) above the at floor perimeter. natural ground level; • Finishing concrete slab should be a minimum of 60 • Insulation boards should be installed with no gaps mm thick.

18 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

The PE sheet and the vertical insulation at floor perimeter The concrete slab ends against the wall insulation so is not yet installed. there is no thermal bridge.

Wooden Sleeper Wooden EPS insulation with a vapor or plaster floor Baseboard barrier on the upper surface

Plancher bois

Ventilation hole Lathwork to Moisture Crawl support the bitumen space insulation • For the implementation of the wooden floor, one In addition a continuous plastic film should be im- should first finish the concrete foundations for supplemented as a vapor barrier on the upper surface of porting the wooden frame. The parting of the concrete the insulation (generally the insulation itsel does not support will depend of the distance between suppor- have a vapor barrier). The vapor barrier should also be ting planks (generally 30 to 60 cm). Foundations are continuous by using sealing tape. linked and stabilized in a concrete slab. Internal sheeting of the floor should be in wood to • The EPS panels are installed between the frames and optimize comfort. The baseboards around the perime- supported for example by the wooden lathwork. Insula- ter of a room improve air tightness of the wall-floor tion should be continuous to avoid thermal bridges. junctions.

19 Design manual for energy efficient and comfortable rural houses in HLJ

2.3.2- Roof

2.3.2.1- Justification Roof thermal insulation has been used in HLJ rural - to increase comfort for inhabitants that will not have houses, especially since the standard of the houses a cold surface above their heads; went from the raw mud house to the clay brick houses Because it is very cost effective and allows to make with tin roof and sheet-board ceiling: local material use of extremely low cost local insulation materials like wood chips, saw dust, straw have then be used that can thus be used in very large quantities and lead to insulate the room above ceiling and can be a cheap to a very low conductance factor. and energy efficient option. However this roof insulation is not always properly 2.3.2.2- Design and sizing achieved both in terms of selection of insulation ma- Obviously roof insulation will reduce heat transfer terial and thickness (optimal thickness according to between the house, that should be maintained in the the thermal conductivity of insulation material used) range of 18°C in the winter and the outside where it as well as in terms of implementation (vapor barrier, can be as cold as –30°C. moisture barrier, sustainable implementation, fire Roofs have to be insulated throughout their whole hazards, etc.). surface in order to minimize these losses and in- Efficient roof insulation is essential: crease comfort by allowing achieving higher inner - to reduce heating consumptions: roof have a large ceiling surface temperature. surface area and can represent a large part of total • Insulation materials selection and thickness house heat losses especially since most houses are The following insulating materials can be used with single floor house (roof area = living space area) the recommended following thicknesses:

Insulating Thickness : Advantages / drawbacks material minimum & Ideal Comments Straw, wood chips, saw More than 50 cm Very cheap. Requires very high thickness for reaching good dust, rice husks, … insulating value Such thicknesses might require to reinforce ceiling structure to be able to bear the load of insulation. Fire hazards since they are combustible. They soak humidity and their insulating value then decreases. However they can be frequently replaced. These natural insulating materials with no negative environmental impacts can also be used to supplement chemical insulating materials. Expanded Polystyrene 20 cm - 40 cm Available even though fairly expensive. Low density EPS (around 15 (EPS ) kg / m3) can be used. Can be destroyed (eaten) by rodents. Fiber glass 20 cm - 40 cm Availability limited in Northern China. or rock wool rolls Extruded Polystyrene 15 cm - 30 cm Very expensive but very efficient. Not always available. (XPS) The best insulating option with respect to energy efficiency.

20 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

2.3.2.3- Implementation recommendations

Galvanized steel Ventilation for roof space Vegetal or mineral insulation

Sleeper Ceiling (wood or Vapor plaster) barrier

• Install a continuous plastic sheet vapor barrier above • Leave a sufficient distance (about 40cm) between me- the sheet board ceiling before implementing insulation tal outlet piping of stove or burner in the roof and com- and fix it to the structure so it is not blown away. bustible insulation (wood, straw, etc.) in order to prevent • Install insulation in a continuous way so there is no fire hazards. Fill the gaps with the insulation with an thermal bridge: whether insulating boards (EPS, etc.) incombustible coating (plaster, rock wool, etc.). or loose insulation is used it should cover the whole structure, rafter and planks that could create very da- maging thermal bridges with a 50°C inside-outside temperature difference. • Make sure that insulation is evenly installed and that it will hold in place and will not be blows away. Good air tightness of sheet roof and closing of the access door to the ceiling is essential especially when loose insulation is used: otherwise winter wind will easily push part of the insulation in one corner of the roof and the remaining part will end up being poorly insulated. In addition air tight attics will act as additional buffer spaces between inside the house and outdoors and add up to insulation effectiveness of the ceiling. • However a tiny ventilation hole should be installed The wooden structure of the ceiling supports the for the attics in order to evacuate the possible resi- loose vegetal insulation. A ceiling plaster board will be dual moisture. screwed under the apparent structure on the picture.

21 Design manual for energy efficient and comfortable rural houses in HLJ

2.3.3- Walls

2.3.3.1- Justification Wall thermal insulation was not currently used in HLJ ru- Efficient proper insulation of rural houses walls ises- ral houses until fairly recently. Traditional raw mud brick sential: houses had no insulation in their walls. • to reduce heating consumptions: walls represent the With the development of new clay brick houses energy main surface area of outside envelope and represent a efficiency of walls increased with the use of double brick major part of total house heat losses; walls with an air cavity in between the brick layers and, • to increase comfort for inhabitants that will not have in some cases, implementation of various insulating ma- a cold surface surrounding them thus decreasing felt ra- terials within this air cavity. diant temperature. However this wall insulation is not always properly Because it can be cost effective and may allow to make achieved both in terms of selection of appropriate insu- use of fairly low cost local insulation materials like reed lation material and thickness (optimal thickness accor- panels (that have to be extremely well implemented) that ding to the thermal conductivity of insulation material can thus be used in very large thicknesses and lead to an used) as well as in terms of implementation. appropriate low conductance U factor (K coefficient with Chinese notation).

In this case, a specific vapour barrier has not been Insulation needs to be added along the edges of the installed. The interior wall is supposed to do this function. windows with the same thickness.

22 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

2.3.3.2- Design and sizing In an energy efficient house with a mass floor, a khang, • Wall thermal mass and position of insulation within internal mass walls, a heating wall, it is thus not ne- the wall cessary to have additional active mass on the outside It is generally said that walls with high active thermal walls. These walls will take a longer time to warm up mass should be used in rural houses: the active thermal and, with intermittent operation of heating systems as mass is the mass towards the inner side of the wall in- farmers currently do (in many houses depending on the sulation that can “soak up” excess heat from heating heating system and outside temperature, heating sys- systems or from solar gains and release it later to living tems are often fueled only twice or three times a day at spaces. meals hours) it might reduce the time laps when comfort If this argument made sense in old uninsulated or poorly is reached. For such houses the thermal mass of the floor insulated houses since mass walls were part of the in- and inner walls, and in the first place the khang itself, is sulation and contributed somehow to reduce impact of sufficient to maintain a decent temperature in the house harsh outside temperature swings inside the house, it is for several hours after heating system is off. not the case anymore in energy efficient houses. • Insulation materials selection and thickness Average thermal mass houses should be designed with The following insulating materials can be used with the a ratio of active thermal mass area versus floor area of recommended following thicknesses: the house of about 3.

Insulating Épaisseur minimum Avantages / inconvénients material et épaisseur optimale Straw panels 30 cm Fairly cheap option but not always available. Requires high thickness for reaching good insulating value Such insulating materials soak up humidity and their insulating value then decreases and proper water proof installation is essential. The use of these natural insulation materials with no negative environmental impacts also support craft industries in rural villages. Expanded Polystyrene 15 cm - 30 cm Available even though fairly expensive. (EPS ) Cheap low density EPS (around 15 kg / m3) can be used but is not recommended. Can be destroyed (eaten) by rodents. Fiber glass 15 cm - 30 cm Availability limited in Northern China. or rock wool rolls Extruded Polystyrene 12 cm- 25 cm Very expensive but very efficient. Not always available (XPS) The best insulating option with respect to energy efficiency.

23 Design manual for energy efficient and comfortable rural houses in HLJ

2.3.3.3- Implementation recommendations

Ferroconcrete chaining

Reinforced concrete lintel

Single or double glazing (Sliding opening)

Double glazing (Leaf opening)

Wood interior bearing

Lime render

Vapor barrier

Plaster board or wooden panel Batten EPS insulation

Moisture barrier (bitumen)

Brick

Ventilation hole

Gravel

Foundation footing ferro-concrete

24 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

• Install a continuous plastic sheet vapor barrier tion dedicated at wall corners, outside / inside walls between the heated space and insulation in order to junction, wall window junction, wall-ceiling and wall avoid vapor condensation within insulation. This is all floor junction as it is discussed here after; the more necessary that insulation used is water ab- • Make sure that insulation is evenly installed, that sorbent: vegetal insulation, fiberglass, ... Vapor barrier it will hold in place once wall is completed and that it should be fixed on the wall to avoid rolling down. If an will not move, fall, slide, thus opening space for huge internal brick wall is built, the vapor barrier should be thermal bridges that are very costly energy wise. If between the brick and insulation; vertical boards like EPS or XPS are used they should • The insulating plaster/polystyrene board has a coa- be mechanically fixed on the wall. ting of cardboard which will act as a vapor barrier; • If water absorbing insulation is used, like straw • Install insulation in a continuous way so there is no or reed panels, a ventilation layer should be kept thermal bridges: whether insulating boards (EPS,…) between outside layer of insulation and the outside or loose insulation is used it should be continuous brick wall . throughout the whole wall structure with close atten-

Wall insulation: polystyrene panel and plaster board. In this case, the insulation to be added along the edges of window will not be thick enough.

25 Design manual for energy efficient and comfortable rural houses in HLJ

Ferroconcrete chaining

Brick

High ventilation for Vegetal insulation Reinforced concrete lintel

Single or double glazing (Sliding opening)

Double glazing (Leaf opening)

Wood interior bearing

Vapor barrier

Straw panel

Lime render

Plaster board or wooden panel

Batten

Flat-iron holding the batten

Wit brick to separate Insulation from wall

Low ventilation for Vegetal insulation

Moisture barrier (bitumen) Ventilation hole

Grave

Foundation footing ferro-concrete

26 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

Ferroconcrete chaining

Lime render

High ventilation for Vegetal insulation Reinforced concrete lintel

Single or double glazing (Sliding opening)

Double glazing (Leaf opening)

Wood interior bearing

Vapor barrier

Brick interior wall Plaster board or wooden panel Brick interior wall

Metallic staple

Vegetal insulation panel

Wit brick to separate Insulation from wall

Low ventilation for Vegetal insulation

Moisture barrier (bitumen)

Grave

Foundation footing ferro-concrete

27 Design manual for energy efficient and comfortable rural houses in HLJ

Implementation of the interior brick wall in front of the vegetal insulation. An air space, ventilated by small pipes evenly, installed is created between the exterior wall and the insulation. In the above picture, the vapour barrier between the insulation and the interior wall is missing.

28 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

2.3.4- Doors

2.3.4.1- Justification Air lock Even though access doors represent only a very small fraction of total house envelope surface area they can have a very high impact on global energy efficiency of a house mainly because they can create unwanted very high cold air infiltration rates in the house.

2.3.4.2- Design The main tips that should be respected to design energy efficient doors are the following:

• Place the access door on the side of the house protected from cold winter winds : generally on the southern façade of the house; • Place the access door onto an air lock, or a room used as an air lock in the winter, and not directly on the living spaces; • Use a double door system with an outside door opening towards the outside and the inner door opening towards the inside ; • Use very air tight and core insulated doors like woo- Outside Inside den doors or doors filled with insulating materials and wooden door wooden door avoid highly conductive metal doors.

29 Design manual for energy efficient and comfortable rural houses in HLJ

2.4- Designing and implementing energy efficient windows

2.4.1- Justification Windows are essential and multifunctional components of rural houses that require very careful design because of their very high impact on energy efficiency and comfort: • They allow light to enter the house while permit- ting views toward the outside; • They allow solar radiation to contribute to comfort and house heating by inletting free passive solar gains, when windows are properly oriented ; • However in energy efficient houses in Heilongjiang, windows are net energy losers whatever their orientation is in comparison with well insulated wall surfaces.

Efficient design and sizing of rural houses windows • not necessarily to use expensive industrially manu- is essential: factured windows, but wooden double or triple win- • to reduce heating consumptions: North windows dows, locally made, combined with efficient and low are large contributors to rural houses heat losses cost night time insulation. though it is necessary to bring the light in, so their Traditional window design in HLJ rural houses has dimensions and their pisitions should be optimized always somehow taken into account energy efficiency • to increase comfort for inhabitants: by making use of double single pane wooden frame • efficient South windows bring in solar radiation windows for instance and or by adding up additional which contribute to comfort and house heating by in- PE plastic glazing to window frame in the winter in letting free passive solar gains. order to increase insulation value and comfort. • windows which are improperly oriented can bring discomfort by lowering radiative temperature. Because efficient window design can be a very cost effective and “win-win” (lower construction cost together with better efficiency) design and construction strategy it is recommended : • to under size windows with respect to common practices, especially in the northern side of houses where windows should be much smaller than on the southern side;

30 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

2.4.2- Design and sizing

The main design and sizing issues that should be dealt with are the following:

• Proper location and sizing of windows:

Southern windows should be large to be able to collect Northern windows should be less than 15% of total nor- solar gains : however they should not exceed 30% of thern wall surface area. Oversizing northern windows is a southern wall surface area. common “lose-lose” error in rural houses of HLJ.

Windows should allow view towards the outside at Window location, vertically speaking, should be as high appropriate location in the wall with respect to internal as possible in order to allow passive solar gain and light layout of the house. to enter the house as deeply as possible.

31 Design manual for energy efficient and comfortable rural houses in HLJ

• Window type selection:

Window energy efficiency will depend on the following parameters that will all affect energy efficiency and windows cost:

- Window frame selection:

Wood frame has good thermal properties PVC frame also has fairly good thermal properties even (low conductivity) and low cost; though negative environmental impact;

Metal frame, whether steel or aluminum, with high Frame size with respect to overall window size: conductivity or average conductivity if using thermal the thinner the frame the better for solar gains. bridge breaker;

32 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

• Night time insulation: Using night time movable insulation of windows will Traditional rural house of HLJ make very little use always drastically enhance windows performances of appropriate night time insulation technologies on and increase comfort in the house. windows and this is one of the major margins of cost Regular double glazing wooden frame windows, with effective improvements. Thin lose curtains are cur- tight night time insulation, are nearly just as good in rently used and their energy efficiency impact is close terms of overall conductance value as the most ad- to nil whereas various efficient technologies can be vanced low-e and krypton gas filled double glazing used as shown on drawings here after. windows with no night time insulation: 1.6W/m2K for the two types of windows. Various technologies and systems are possible according to local availability, costs and social accep- tance.

Rod attached on lintel Thick curtains Shutters fold up within window frame Self adhesive seal Internal foldable Interior bearing shutters covered by the curtains

Movable insulation panels (EPS panels straw panels)

Perfect air tightness with window side and bottom

33 Design manual for energy efficient and comfortable rural houses in HLJ

2.5- Avoiding • Comfort impacts of thermal bridges are negative thermal bridges because they create cold zones;

2.5.1- Justification • In addition thermal bridges have the following ne- Thermal bridges are those specific locations where gative impacts : envelope insulation is interrupted leaving privileged - Building durability by leading to large temperature zones for heat transfers between inside and outside swing within building structure; to occur, which has very negative energy impacts: - Paints and coatings durability are affected. - They may generate building pathologies like conden- • For example, a 2.5m tall wall, which is between sation, molds, fungi (…) that may induce serious two 20cm concrete slabs and insulated by interior human pathologies. Such pathologies are shown on with 10cm EPS, the thermal bridge at the end of the pictures here after for energy efficient houses built slab will multiply the heat losses of the wall by a fac- in HLJ. tor of 2;

34 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

2.5.2- Designing thermal bridge avoidance Avoiding thermal bridges require detailed knowledge of envelope discontinuity treatement. Thermal bridges will be avoided if one can take a plan section at every house level and at several significant cross sections and draw a continuous insulation line around the house as it is shown on the plan here after.

Continuous insulation around envelope avoiding thermal bridges

Typical thermal bridges may occur (non exhaustive list):

At wall ceiling or intermediate floor junction At wall-floor junction

35 Design manual for energy efficient and comfortable rural houses in HLJ

At wall corners At outside-wall / inside-wall junction

At window perimeter

Detailed and careful attention should be dedicated to those areas and detailed blueprints should be produced to construction teams.

36 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

2.6- Infiltration and ventilation

2.6.1 - Justification 2.6.2- Design Fresh air admission in a rural house is required: Hygienic ventilation can make use of: - For hygienic reasons : human activities currently - Mechanical system (by a electrical ventilators) require fresh air inlet of 15 to 20 m3/h person if whose flow rates should thus be adapted to recom- one does not smoke in the house and 30 m3/h if mendations here above. Ventilation outlets should be one does ; in kitchen and bathroom and small openings for fresh - To be used in combustion chamber of stoves or boi- air inlet can be made in the living spaces (living room, lers. bedrooms, ..); Required hygienic air change can thus be as low as 50 - Static natural ventilation (by natural convection) to 80 m3/h for a three person house thus representing with high outlet vents in kitchen and bathrooms and between 0.2 to 0.3 air changes per hour in a 250 m3 low inlet vents in the living spaces. house. The static natural ventilation is a simple technique, In addition to these hygienic ventilation needs, com- but it is less regular and can not be controled or be bustion air should be supplied to stove and burners ajusted as required. when such systems operate. High efficiency ventilation technologies such as cross Ventilation rates higher than required will lead to ex- flow heat recovery ventilation systems that could be cessive heat losses. very beneficial to energy efficiency and comfort in On the other hand reducing ventilation below the rural houses are beyond the scope of this manual be- above standards will lead to low air quality with ne- cause of their cost and their limited availability in the gative effect on comfort and potential negative effect Chinese market. on health.

Inlet vent inside the partition of a living room Inlet vent above a khang

37 Design manual for energy efficient and comfortable rural houses in HLJ

2.6.3- Implementation recommendations

• Air ventilation for combustion Ventilation for stoves and burners should be directly higher than hygienic needs and the air draft created feeding the stove or burner with outside air and not would excessively cool the living space and negati- cross the living space especially because excess vely affect heating needs of the house and comfort air volumes required for fuel combustion are much of inhabitants. Towards the chimney Towards

Flow rate should be made adjustable by a damper

Vers l’extérieur

Inlet pipes for combustion of wood, coal or straw should Air intake outside, for the stove of the kitchen lead directly to the stove

38 Designing and building rural houses with better energy efficiency and better thermal comfort in HLJ

• Hygienic air ventilation

Inlet pipes for fresh hygienic air should be preheated by traveling through khang or other heating element in order to avoid uncomfortable cold draft on users. One should insulate the exhaust ventilation pipes in order to avoid condensation of the water vapor and even the risk of freezing.

Air intake for ventilation, North side of the house Air intake for ventilation, beside the access door

39 Design manual for energy efficient and comfortable rural houses in HLJ

Chapter 3 Construction of a very low energy consumption house

The present chapter introduces the concept of very • close attention to natural ventilation systems that energy efficient house that could be built in Heilon- should allow sufficient air for good insuring air quality gjiang by bringing efficiency standards further than in the building and for allowing combustion of stove the standards implemented in the FFEM project and while not creating uncomfortable air streams on oc- up to the level of so called « low energy consuming cupants. houses » which are currently being built in Western Europe even in climates not as cold as Heilongjiang Also internal thermal mass of the house has been (typically 3000 DD while in HLJ many places expe- decreased when compared to conventional house. rience more than 6000 DD). These houses would lead, in the cold Provinces The blueprints here after introduce such a house that of Northern China, to much lower heating energy features, among others, the main following energy consumption and related environmental impact to- efficiency components: gether with allowing high comfort standards for • ceiling on attic insulated with 25 cm EPS supple- users. mented with 40 cm wood chips The suggested design has been achieved by adapting • brick wall with 25 cm EPS and internal 6 cm brick a current floor plan for a typical dual rural house. • insulated floor with 18 cm uncompressible EPS It makes use of technologies and components cur- • decreased size of North windows with respect to rently available on the Chinese market even though current practices and use of double windows with windows might require shipment from distant sites. double glazing on each one, the interior one being The main energy efficiency features of these houses argon filled and low emissivity are the following: • air tight thick night time shutters or internal mova- • high level of thermal insulation for walls , roof and ble insulation on windows ground floor. This insulation has to be implemented • detailed thermal bridges and air tightness treat- according to state of the art rules such as: ment of building envelope - selection of appropriate durable insulation compo- • very air tight lock on entrance door nents; • fresh air for stove combustion carried through spe- - implementation of vapor barrier; cific duct with adjustable damper - perfect continuity of insulation implementations and • fresh air for occupants through duct work circula- rigorous treatment of thermal bridges , which should ting through khang for preheating be planned, sketched and taken care of in a very detailed way. • very energy efficient double windows featuring ideally low emissivity and argon filled double glazing interior window and double glazing outside windows, those windows high thermal performances being supplemented by energy efficient (air tight) curtains or other internal movable insulation;

40 Construction of a very low energy consumption house

41 Design manual for energy efficient and comfortable rural houses in HLJ

42 Construction of a very low energy consumption house

43 Design manual for energy efficient and comfortable rural houses in HLJ

Thermal calculations, which have been carried out to conditions for village populations. It therefore shows evaluate the energy consumption of this rural house in that modern techniques can be used within the fra- the climate of Heihe shows that the consumption of coal mework of self-help housing construction where (calorific value: 5800 Wh/kg), is reduced to about 1.6 ton they bring about a level of comfort which many city per year to maintain a permanent temperature of 18 °C dwellers in cold areas would envy, without, however, throughout this house. It means that this consumption requiring changes to local habits, in particular with will be even lower because the users do not maintain regard to heating methods. this temperature throughout the house all winter. The first houses developed in this way were of an CONCLUSION exemplary nature and have already served as a model The present guide was drawn up within the fra- for the construction of 1,300 rural houses in Heilon- mework of a cooperative project between France and gjiang province and we have no doubt that Chinese China with the aim of reducing emissions of gases civil engineers will further improve the performance responsible for climate change. and quality of these constructions.We are looking It points out the special attention paid, within this forward to following these advances to which we programme, to the construction of rural houses in have made a modest contribution in opening up a the cold areas of China and the improvement of living path toward more sustainable development.

44 Coordination: ADEME in partnership with the French Ministry for Ecology, Energy, Sustainable Development and Spatial Planning, the Construction Department of the Heilongjiang Province of China and the French Global Environment Facility (FGEF)

Editorial: Robert Celaire and Alain Enard Photographies and illustrations: Robert Celaire and Alain Enard Design: O Communication About ADEME

The French Environment and Energy Management Agency (ADEME) is a public agency under the joint supervision of the French Ministries for Ecology, Energy, Sustainable Development and Spatial Planning, and for Higher Education and Research. It participates in the implementation of public policies in the fields of the environment, energy and sustainable development. The agency makes its expertise and consultancy skills available to business, local communities, public authorities and the general public and helps them to finance projects in five areas (waste management, soil preservation, energy efficiency and renewable ener- gies, air quality and noise abatement) and to make progress with their sustainable development procedures. based inks www.ademe.fr

Construction Department

of the Heilongjiang Province 6575 April 2009 • ISBN 978-2-35838-046-1 Printed on European ecolabel paper with vegetable-