THE TIMBER TOUR, 17-21 MAY 2005 AUSTRIA AND SWITZERLAND

FEEDBACK SEMINAR: NOTES Collated by Chris, 21.05.05 amended and added to by Sandy 23.05.05

THE PROJECTS VISITED

1. THE CARDBOARD HOUSE Architect Walter Unterrainer. Two dwelling units, façade in cardboard behind glass, nearly passive energy standard (one third of normal energy use, 21kwh for heating). Built 10 years ago. About 3mm of th eair layer in the cardboard gets solar heated (sun penetrated further in in the winter)- then the U-value of the wall is 0. U-value 0,2, but overall 0,12 due to this. – a kind of air curtain. A wall with 0,1 is usually 40cm thick, this one is 28cm. (8+6+14) Need for work with dynamic U-values not only static. This is a more offensive or active design strategy using solar in the building facades – as opposed to just heavy insulation. Generation house, to be extended over the garage - flexibility - advantage of the clear span provided by the massive wood. Most mounted in one day. Query regarding some vapour and damp problems on the wood – as in other houses. WU said it functions as regards vapour. Says cardboard and timber helps regulate humidity. Solar thermal on top quarter of the façade. Flax insulation. Quite cheap. Has done 4 “cardboard” projects including an office, a veterinary hospital.

2. SOHM DIAGONALDUBELHOLZ FACTORY Andreas Kempf, www.sohm-holzbau.at 40 employees, also does ordinary timber work Cost E80,000 for , new one costs three times more (not yet mounted) Up to 16m long, 580-620cm broad, 8-30cm thick produce 8000m3 per year, of which 6000 DD, 15% sold, rest used in own projects. Cost E500 per cu.m. S10 wood quality, 95% local pine. Wall elements have one side with finished quality. Also quite complex section: 100 dubelholz, board, 15cm hemp insulation, softboard… Doing other things to, standard elements etc. CAD. Said about same cost as glueing 12RH wood and 7%RF . Dowels 20mm diameter, rammede in at 150 bar pressure.. At 15 degree angle., double layered. Even wood movement, no big cracks/gaps can develop Drying time of glue? Stress after 3 days. The local timber is not stamped, only the packaged type has been machine tested: an issue of ceetification if export?

3. HOTEL POST EXTENSION KLH – kreuzliegendeholz, 3 ply, blockboard core Need for extremely quick mounting for the hotel. 9 weeks start to finish – or else the contractor must pay for the rooms! Weathering uneven, and some parts had been coated.

1 On basement. 9cm walls + 3cm insulation + 9cm. Slab 12-14cm. Also: presentation about traditional shingle facades. Local larch – 80 year life – must be cut by hand, not saw which destroys the cell structure. 2-3 layers, but 4 on roofs. Old massive wood (block-haus) farmhouses were often clad with shingles later on.

4. BLONS COMMUNITY CENTRE AND SCHOOL Historical project and local pride – avalanche in 1953 killed about 60 villagers, forest planted, now harvested for these buildings. Tiny school, for about 10 kids, nice indoor space, warm atmosphere and good daylighting. Diagonal. 42cm of massive wood, curious - no insulation. 8cm horizontal, 22 vertical, 8 horizontal. Roof 24cm massive wood plus 12cm insulation. School: bounce in the floor (okay!) Local sheep wool felt Beech load bearing compression plates at top of columns Key process – local timer, local artisans, local history, show their skills. School produced by Sohm

5. NEW HOUSE ABOVE BATSCHUNS Next to Baumschlager artist studio Passive house. E250,000. Massive wood with earth paint with rough finish. On just 8 concrete pillars, Triple glass U=0,6. 6,2 metres wide. 6 hours mounting time for the massive wood elements. Heat pump with ground air system. (ca 18cm pipe, 25-30m length, works a lot from –16 to +1 in winter, works less well in summer. Tightness: law requires 2,5 ach, passive recommends 0,6, this was about 0,45 (at 50Pa).. WU asks for 0,5 in his contract Super efficient burner. Verandah in steel not completed yet. Nice detailing. Weisstanne instead of larch. Not diagonal because it cantilevers 2 direction – can be solved in other ways says Birger.

6. BATSCHUNS PASSIVE ROW HOUSES Group of 4+2 units, including WU’s own house. 4 units are 6x12 metres and 2 floors, the 2 units are 6x9 and 3 floors. 1240sq.m site, owner wanted 4-5 units, WU proposed 6. Importance of the density issue . efficient land use, which is also encouraged. The first Austrian passive houses. Detailing around windows etc. Removable facades. Not even fireplaces. 1997. 23 degrees in winter. Designed for family. (for heat, need a family especially at the ends!) Simplified electric solutions, avoid unused plugs, 14 cm high skirting, cleaner room geometry Anthracite paint on ordinary glass, toughened only around holes. Solar hw, but co-owners in a PV plant down the valley, no point to do that on every house. Wheelchair ramps. Very special kitchen furnishing, storage maximising! All details drawn by WU down to the last thing!

2 7. WALTER’S LECTURE Inspiration from traditions. And seeing the qualities in “poor” architecture, which much so-called rich architecture often doesn’t have. Simplicity. Importance of understanding and designing the ageing of buildings. Finnish in the 1960’s! Essential to combine with craftsmen. Early projects from th elate 1980’s. Now passive houses for only 2-4% extra cost. Austrian system for encouraging green buildings. Loan increases according to how many green points a building gets. And 50% subsidy for conversion from fossil to wood heating. County laws are all different. A wall section: cladding on battens fixed to the stiff insulation mats – 30 cm insulation .- moisture-open barrier – loadbearing zone 10cm with insulation and electrics – interior panels.

8. TEXTILE FAÇADE HOUSE Cow shed textile costs E4 per sq.m, material??, 80% airtight. Usually made 100 x 2m rolls, making the house was a tailoring type job. 3 colours were available. Black was chosen. Culvert pipe 20cm, polyethylene, 25m long, at least 1,2 metres deep, 40cm sand around it compressed, filter at the intake. Cleaning with hose, must slope 2 degrees, one of them needed no cleaning after 3 years. Norway says there is a mould risk in small pipes. Interior walls: 3cm earth panels 1,2 metres long, and earth plaster. (no straw but flax fibres) Windows: 0,5 glass whole windows 0.8, maximum size 2,5 metres dimension, light frames. Glass emissivity: low e-factor Air to heat exchanger: ceiling inlet in living room, outtake in kitchen Wood burner, 22 sq.m roof PVs. 22mm massive wood becech floor Wall: from outside: textile on battens, OSB board,40cm cellulose, 4 wood, 3 flax and electrics, earth board.

9. HOLZBAU LOT FACTORY Happy workers, good atmosphere. Family, 15 employees. E800 per sq.m, good detailing – high quality level at that price! 20x20m hall and adjacent office (26x6 m and which has almost passive standard) , great daylighting, competition 7 architects. Bio heating from own wastes., 5m diameter silo. OSB (oriented strand board) facades including a 0-emission chipboard. “Living board” Radiant ceiling panels Modular, 5x2 metres. Fibre cement strips on butyl strip as covers on cheap façade, and no horizontal joints, just overlap. Crane detail and console. Roof flaps for summer ventilation, 4 on each side Good for parties! Drive through.

10. MÄDER PRIVATE SCHOOL Churerstrasse 24, next to Steiner school and a new very elegant WU passive house.

3 Cost E1,000 per sq.m and 98 sq.m, very simple plan, could be a house, temporary, movable, etc, designed self build, standard cheap window cheaper too. Cheapest everything, but people are asking him for houses like this! Roof also massive wood, with sound absorbing profile of 12mm channels which also take electric wiring. Rainwater siphoning system – in case the normal runoff doesn’t function. Floor slab is insulated under. Play areas, tree, nice door surround detail. Massive wood with orthogonal dowels (even pallets used as verandah, see the floor cracks), all cheap materials, rough surfaces, texture nice. White pine. Many of WU’s buildings are very reasonable costs. Simplification is a key, but then a few high quality details. Understanding of materials and structure.

11. OELZBUNDT HOUSING Apartment block. architect Kaufman, early project, culvert intake only 2m high, too low to avoid possible vandalisation. The energy-saving glass was not best, too dark, should have had about 25% more glass. Energy: overestimated internal heat as based on families, and equipment, but many were occupied by singles, so they were not heated enough. High acoustic standards. Stimulated others, gained acceptability, one of the first examples, about 6 years old.

12. SCHINDELEGI SITE, TSCHOPP Surprisingly poor site health and safety! But good skills levels, all seemed to know what they were doing! Composite brettstapel and concrete floors. Too many layers! Attractive finished ceiling, with acoustic profiling. Some steel too, clad in plasterboard. Weight saving saves foundation costs … but again they must add weight to solve the acoustics in the floors. Cheaper to get rid of wastes wood than concrete. 14 days for whole structure of 3 floors, wood parts just 2-4 days. Total building time 2-3 months. Fermacell panels. Reasons: wood is popular, ecology, breathing, lightness, no wet site jobs. 6-8% more expensive, but maybe save some due to quick time. Fire regs have changed recently to allow 6 floors.

13. TSCHOPP HOLZBAU Hochdorf. Ivan Tschopp after father. Brettstapel is one of three divisions. Timber - Interiors - Bresta 17,000 sq.m per year. 30 apartments. Bresta system since 1995, 65 employees including 7-8 trainees. Clients come to them with own architects mostly. Dowelling and . Direct from CAD to machine shops. Good quality working and effective machines setup. Showroom upstairs with sectional models etc. TQM quality teams.

4 NHGKL II (two) wood quality which is about S10. On the visible wood, other was industry quality. They set L/600 bending on floors, stricter than normal /300. Length mostly only 4,80.

14. PIRMIN JUNG LECTURE www.cadwork.ch 110m covered bridge designed in 1780 … focus on craftsmen Showed a series of projects and how he contributed to developing new timber solutions, worked with Natterer and Tschopp. He started dowelling, invented the concrete-brettstapel combination. Also did the first timber lift shaft. Avoid lateral members, columns on columns . avoid sinking of the timber parts. 12% Swiss houses now in wood, was only 3-4% ten years ago. Sports Hall Lucerne with Bresta walls and 18x7 m stage folding down. Market is coming he thinks now for the multistorey.

15. RENGGLI FACTORY 100 houses per year, more bigger buildings now. Average age workforce 36 years, 120 people. Also a family dynasty From standard 8,5 litres of oil per year to Minergie 4,5 litres oil, to passive about 1,5. Have standard houses including passive, with flat roofs. Very unecological materials use, but could easily be bettered. Insulation, polystyrene, glues, tropical , etc. Timber from Germany, others. 1,0 glass, 2 month building time, 22cm insulation for Minergie Prices E490,000 to 600,000 180sq.m Often cellars. E2,700 per sq.m 4 articulated lorries per house. Thinks not much future for brettstapel in walls.

16. LYSS Architects Itten and Brechbuhl. Forest Training Centre. Alan Kocher director. Great! Very legible building. Opened 1998. A Foundation, owned by 11 cantons. Was to be conrete, previous director insisted on wood. Timber industry is on a decline. They also use it for other groups now (police courses) – gives them more contacts. Clear felling not allowed since 1901. All furniture is “red heartwood beech”. Wet wood biomass boiler, about 320kW – more than needed. Calculated need about 1300cu.m per year but in fact they only use about 650. Land costs are extremely high, can be 85-500SFR per sq.m.Foundations: swampy area, 320 friction piles, due to lighter weight of a timber building their length could be reduced by 4-5 metres. Columns – 11 metres, 300, local, 3 cuts, compression tested up to 100tons but their load is only 40. Abies alba, silver . No sticky sap, and 10% cheaper than Norway . Steel consoles. Floor construction: suspended MDF acoustic ceilings below rough roundpole, then planks, cheap garden tiles made of recycled materials, fibreboard, beech parquet. Pinus cedmbra some places, distinct aroma even after years. Budget 42M SFR including land, was cut to 40, final around 33. About 2,000 cu.meters of timber was used (same as grows in Switzerland in about 1,7 hours). 4 degree slope roof was preferred to required flat roof.

5 4 escape routes in each class, fire regs, 4 requiremetns: compartments, doors., concrete crosswalls, sprinklers, escapeways and ladders; then wood stairs were allowed too. 15-17 degree unheated corridors (semiclimatised) Four student hostel sections, set transversally, duplexes, nice. Solar hot water. Black solar shading curtains come down inside the glass and timber ledges along the facades. Prefab external wood stairs mounted by crane. Facades in larch. (Chestnut is very good too but expensive). Also larch windows, nice but can twist a bit. NO chemicals used at all in the whole timber building, except a bit on some parquet floors. Design goals: reasonable costs – sustainable materials – no luxury – low maintenance. Floor construction including round pole.

17. BIEL-BIENNE Engineer Jurg Conzett, Chur. Architects Meili and Peter. Bern canton; 350 students; old buildings around it. Very interesting issues of scale, proportions, architectural mastery or not. A very strong, impressive building, but many things maybe not quite successful. Some of us didn’t like it. Useful video showing the construction process.. Concrete core, timber prefab cells, 10m deep, on each side. Concrete stairwells with glass roofs. Cooperation between several factories, to provide sufficient capacity. Prefab box beams (lignatur) and elements, using partly quite cheap wood pieces; sawdust-concrete mix on floors. Black walls, dark and unnecessarily wide corridor, not a legible building, unclear entrance (two of them, and no clear reception), functionally not very good either. 10m span elements, 3 storeys high. Untreated oak (from Schaffhausen) façades. Local pine (sylvestris) from the Bern area.

And much more!!

6 DISCUSSION

Key Themes and Issues • Prefabrication • Speed of erection • Scale of construction – crane /handling • Integration of fabrication and erection • Industrial products and engineered timber • Localised markets – limited radius • Minergi / energy standard • Buy 2nd hand equipment (eg Brettstapel machine) • Modern style accepted – architectural diversity • Flexibility – social agenda • Fiscal /loan incentives for eco-building • Application for non-domestic buildings (UK) • Eco-building @ low budget • School buildings as educational tool • Fire regs and insurance • Quality and fitness

Over page – Roundtable discussion

Thanks to everyone for their participation and their contributions

Sandy Halliday & Howard Liddell Gaia Group The Monastery Hart Street Lane Edinburgh EH1 3RG 00 44 131 557 9191 [email protected] www.gaiagroup.org

7 Birge Sandy Willi Bernard John What • Engineering • Conversion • eye opener • need to • Inspirational learnt is OK and not in relation to • contacts and move to learning difficult Egan and network prefabricated opportunity • industrial want to wipe approach • new spying my desk and • confirmed appreciation develop a fears about opf modern prefab factory costs of architecture tooling up What • convince • fire, energy • incentivising • need • narrow change customer regs minergi prefabrication minded • do a project • revisit future houses and building approach to to proofing • mass timber integrity design • demonstrate discussion re- longer terms • try to attention to and change flexible design develop detail production • fiscal simpler ???? after incentives • develop eco- • integrate house market examples into • simplify CPD designs to publication bring down and maybe cost green guide How • build a • publications • need to find • import a • show project (slow) and lectures - out more ready made pictures • Need specialist little • badgering building • put detail knowledge publication for • build sheets and from pilot the web? something in pictures on project • update the brettstapel website • do it myself regulations • look for report to cleints for integrate the more above - run modernist seminar? buildings • build our • form the own stuff scottish flat • not just roof/ housing ecominimalist • more tours society • building control officers (CIC) • Look to research in modelling culverts, acoustic transfer, thermal/air/m oisture issues, compression resistance, slippage

8 Catriona ESA Juarma Howard Chris What • good mix of Knowledge of • See how • Conversion • Shows value learnt group brettstapel brettstapl has to pre-fab – of study tours experience developed speed and • importance from early efficiency of pilot days important projects • Similar • Fire values in regulations – Austria and test and show Finland • Specific opps for brettstapel – not ubiquitous • Value for money of passive houses and very reinforcing What "can do" Attitudes to How challenge Change change attitude • Brettstapel ecological 1. build on assumpotion Fabrication existing • that you need 2. Fire adding a new to minimise 3. Energy option amount of wood How • talk to Own research • Need good Identify • need to director and examples with existing persuade • advice/discuss good companies , planners and dissemination ion with information build on politicians of tour • going indudtry of • Include people who • need to for demo 130 wood timber ???? have skills – respect how project in one product not reinvent we got here place • get producers wheel. • people in the Start fire regs industry debate Learn interested from here – • a targeted what did they group (need do to get more technical them changed information) • Exemplar • raise at x- projects in my party group work because of • Case study interest in in minergie affordable standard and housing. passive standard

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