The 2005 World Sustainable Building Conference, 01-136 Tokyo, 27-29 September 2005 (SB05Tokyo)

ECO - OFFICE BUILDING: REALISED PROJECT: NAVAN: IRELAND

Paul Leech1

South Corner Roof New Existing Diagonal section: North South 1 Paul Leech BE B Arch RIBA MIEI Architect Engineer

Paul Leech: GAIA ecotecture; 11 Upper Mount Street, Dublin 2, Ireland Tel: + 353 1 6610957 Fax: +353 1 6785124: author e-mail [email protected] [email protected]

Keywords: timber structure, venturi, natural ventilation, deciduous shading, double facade, clay products, eco cement, solar chimney. Abstract The 5 storey timber office building is currently (March 2005) under construction on site; already roofed, clad, glazed with many interior specialist/ services subcontracts in progress, to open within a few weeks. By the time of the conference in Tokyo the scheme will have been completed and occupied with many practical lessons learned which we believe may be worth sharing at SB05, as a precedent case study, and hopefully as an exemplar. The building, as completed, will be presented at the conference with an emphasis less on description of the specific design but more on the generic lessons learned. Some months of occupation will already have yielded some results especially over the summer season when office cooling will be an issue. Early user feedback will be reported. The salient features for relevance to SB05, in no particular order are: Five storey office building completely of engineered timber structure and fabric; Swiss/ German engineering and technology (Pirmin Jung; Projekt Holzbau Merkle) within an overall ecological design Philosophy; Brettstapel;Kerto. (Displacing concrete and steel while meeting many stringent criteria of Eurocode 5, fire safety issues etc.): Primary-energy use target = 50 kWhrs/ sq.m per annum. Natural ventilation using a double wall of glazing; (engineered composite timber window systems with trickle ventilation devices) Passive solar chimney and a roof-light ventilator on the Venturi principle to assist natural ventilation via an atrium: Passive solar space heating; carefully oriented space planning: Passive cooling by deciduous shading , night purging; undercroft culvert plenum: Very strategic, limited, targeted auxiliary heating and cooling; gas heat pump source: Thin shell clay rain screen cladding on timber battens; very careful application of embodied energy for long life / durability: Baubiologie principles adopted: lime plaster/ tierrafina, interior finishes integral blind systems: cellulose insulation; sisal paper vapour check ’breathing wall’: Eco elevator; 5 stops; No Machine room; in shaft low energy electro mechanics: Transport -Modal split away from the private car: very restricted parking: generous, secure bicycle parking facilities for both members and staff: showers ,changing facilities and lockers: Owner –occupier client: Life Cycle analysis: Community ownership of a financial institution:Participative group process with member board and staff: Sustainable urbanism contribution in macro scale: All externally sourced electricity from renewable sources; natural gas fired heat pumps: Photovoltaics powering servos for intelligent BEMS system and for water pumping of harvested rainwater: Solar Thermal panels for hot water supply: Green roofs for oxygenation, insulation and amenity: Green terraces for respite and stress relief: Peace Garden dedicated to global respect, solidarity and understanding

SYNOPSIS re SBO5 topics under heading: Energy Use and Climate –Technology Design for Energy Conservation

Low Energy/ Energy Design Concepts -‘Factor X’ thinking 2; use less of everything, much more efficiently; e.g. use six times less twice as efficiently gives a reduction factor of 12. - Low embodied energy in the fabric; - Basic passive design methodology: orientation of volume for solar gains when required; mitigation by shading / location when not. - Timber structural engineering6

- 948 - The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo)

Design Process / Decision Making Process Holistic- art of architecture; 3 pillars of sustainability; economy, equity, ecology: Client 4 involvement- participative; pluridisciplinary; townscape / urbanism issues resolved; determination to see decisions through on site. Design Tools Ecotecture is the main design ‘tool’ - with the benefit of research and 25 years experience in this field with feed-back from previous designs; we are skeptical of deterministic, reductive design tools; we have found that holism ‘works’. Innovative Materials The main 5 storey construction is of timber Glulam/ Kerto/ Brettstapel 5-‘stacked planks’- engineered softwood jointed with hardwood (ribbed) dowels (see detail below). The outer rain screen cladding is of very thin clay tile, to a very high quality control standard, on fire stopped timber battens (good up to 20 M) on cellulose insulated brettstapel5. An airtight moisture transfusive ‘breathing’ wall construction is used for healthy indoor air quality. Baubiologie principles are also applied inter alia Clay terrafina7 and clay paint internal finishes. Intermediate floors are of exposed brettstapel soffite5, with sand topping to floor services for power/data and telecoms. The engineered softwood window system (composite with thin metal cladding) has high performance glazing.8 (with hydroelectrically derived aluminium for reduced embodied primary energy- for composite UV and weather protection to timber)

Clay Products; thin clay rain screen cladding; GIMA / Moeding 3 Colloidal clay dam proofing Voltex damp proofing in lieu of petrochemicals 9 Clay wall paneling / finishes7; clay paints10 Double window wall 6 M high of engineered timber 8 Eco cement from Granulated Blast Furnace Slag aggregate (GBFSA)11

Timber Frame Construction.

Ref 6 Steel connections6, covered with at least 50mm Timber

It was an intention in ecotecture to design floors /ceilings, lift shaft and stairways in timber structure, making this among the taller timber-framed office buildings in the world, within contemporary practice, regulations and standards. The type of structural system being used is a framed structure of Glulam with brettstapel kerto / panellised infill. This is highly preferable according to ecological criteria: glues are avoided as much as possible. Detail design, calculations and modelling have established the optimum, structurally.6 In the brettstapel system being used by Merkle Holzbau beech dowels (at 8% moisture content) are inserted, under pressure, through slightly smaller drillings (typically at 12% MC): As the moisture contents equalise, the hardwood dowel expands and the softwood shrinks becoming an integral solid timber construction, with attractive fire safety characteristics, while retaining very low embodied energy. This component is manufactured to a quality control level which allows it to be used directly as a finish eliminating other materials. N.B: It is a matter for any other design team to satisfy themselves professionally in relation to their own design projects /regulations jurisdiction and not to rely on this precedent without the utmost specialist rigour on a case-by-case basis. The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo)

Timber Engineers comments (Pirmin Jung - Ingenieure fur Holzbau) 6

“General comments: All relevant load bearing elements in this building are constructed with timber. The timber engineer was involved in a very early stage and could therefore choose an optimal structure. It is important, that the specialised engineer is involved from the outset. Only this way, an optimised structure in terms of costs, lateral stability etc. can be chosen. Technically it is possible to build up to 8 levels nowadays. The limits are mostly given and set by the laws concerning the fire protection. The first main key point of a building in such a size as the credit union building is, to solve the fire protection. After consultations and having approval by the fire officer, the detail designing of the structure starts.

Grossweid 4 Tel.: 041 459 70 40 Mail: [email protected] CH-6026 Rain Fax: 041 459 70 50 ww w.ideeholz.ch Objekt: No: Phase: PIRMIN JUNG

Detail: scale: Date: Ingenieure Fire protection: Inhalt: gez: für Holzbau GmbH Content:

To match the requirements for the fire safety set up by the fire officer there were a few points to pay attention to:

Load bearing structure including the connections with a fire resistance of 60min

Surface of lift shaft and stairways are non combustible

The structure of lift shaft, outside wall, stairways as well as the ceiling is air- and smoke tight sealed.

The load bearing structure of the walls is generally packed either with 2 layers of Fermacell boards from the outside, or with 100mm timber from the inside. This way, the structure of these walls is protected for 60 minutes in case of a fire.

Section of external wall at typical cill / head to ‘Box’ Window

Load bearing structure: Members where vertical load occurs is running directly through the whole building without having any horizontal members in between. This way, the shrinkage of the vertical members and the whole building is minimised.”

Comments of Projekt Holzbau Merkle 5 “Preparing and planning the structure happened in a very harmonic way. To finalize and define all relevant parts in a 3D-Computer Model and to generate complete elements in the production from this model was the correct decision, when looking back (faster, right on time, optimised procedure on site). We see the works on this building as absolutely being on the right track for the future. It is bold and future orientated. This building shows that the material timber is destined for buildings with high quality in terms of high architectural demands. For the vapour barrier, Merkle used products of the company AMPACK.The fibreboards came from the company XELLA, Type: FERMACELL.The insulation came form the company STEICO. Product: Steicoflex and Steicotherm Timber: 100% pine Glulam and non visible timber studs: Timber (pine) form Germany; Kerto Q came from Finland Visible Brettstapel: the material came from Sweden”

Acoustics

There is a synergy between fire safety and acoustic considerations in massive composite timber construction. Imperforate fire barrier ceilings with the services zone above the floor were used. The sand layer in a card ‘egg crate’ ref mitigates airborne and structure sound transmission

Fire Safety A fire-engineering approach has been adopted. Preliminary discussions were held with the Fire Officer, several experts have been consulted including Dr Howard Morgan30. A Kone evacuation standard lift has been installed: A very high standard of detection and alarm has been applied. The charring rate of timber is a key criterion and the careful detail design to avoid ignition of small timber sections in a situation of updraft is crucial. Massive timber has inherent fire safe qualities as compared with light sections. Surface spread of flame is a key issue and may be addressed with specialised coatings where required. However, care must The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo) be taken to minimise the use of any toxic substances affecting indoor air quality. We have used Bollom32 Intuclear et al. The stairwells/ Venturi/ Link/ Building have all been provided with smoke ventilators to allow the Building be evacuated and smoke to exhaust to atmosphere, all controlled via the automatic smoke and fire dampers/ BMS fire strategy/ in the Building Fire Alarm System. A reservoir for initial smoke containment of volume 64 cubic metres has been fitted below the Venturi ventilator. All of these features would have overriding control by the fire chief in the event of fire.

Steel Structures There are a number of external lightweight steel structures attached to the basic timber volume; In general these steel structures use cold-formed pressed steel structural studs and multibeams, circular hollow sections, and a minimal amount of hot rolled sections only where necessary. Galvanised steel is used to the weather side: steel is chosen for small neat sizes, incombustibility and long life. Note; Many eco buildings ‘wear their heart on their sleeve’ with timber cladding which will not last in a moist temperate climate like Ireland’s; our view is that a long design-life building like this with low maintenance should have only very durable long term materials on the exterior; the galvanised steel is matched with sheet zinc cladding where required. This lightweight ‘filigree’ of steel is wrapped around the basic timber volume, (omitted in illustration 12)

Responsive Building Elements Deciduous shading to glazed walls; in synergy/ phase with natural processes; oxygenation; cleansing of urban air especially in dry season of particulates and other toxins. We consulted Marta Lam13 at University of Brighton in relation to our design for deciduous shading on the brise soleil pergola on the SE SW and NW facades of the banking hall. The photograph shows their experimental rig at the University where Virginia Creeper has been used for seasonal shading of a room for comparison with a control room unshaded; Drops in temperature of 5 degrees C have been recorded in the test room with enhanced indoor air quality. This low energy natural cooling technique displaces primary energy use in active cooling . University of Brighton; M Lam13 Active solar thermal panels for hot water supply. 14 Active solar photovoltaic panels used inter alia to power servos on ventilation windows etc tied into BEMS 14 Double walls of glass acting to preheat incoming air in winter by trickle venting the cavity space; 8 interstitial blinds and plants Weather station informing BEMS (Building Energy Management System)15 Passive solar chimney16 15 - hypocaust effect- most active at time of greatest need Atrium to Venturi16 15 roof ventilator combining stack and venturi effect- augmented by solar chimney Colloidal clay water proofing 9; gels on contact with ground dampness forming impermeable layer in lieu of petrochemical products for damp proofing.

Innovative Building Envelope Brettstapel wall / roof with ample Steicoflex/ Steicotherm cellulose insulation 5 Double window wall of engineered timber glazed frame 9

The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo)

Clay Cladding 3: 30 mm cavity clay Moeding 3 tile compared with traditional cavity fired brick wall of 90 mm; nett difference is 90 mm vs 15 mm; a factor of 6 reduction in fired clay but enhanced performance - reduced dead load; concomitant reduction of structure and substructure. Whereas the fired terracotta has relatively high embodied energy per m3, the mass quantity is minimised by hollow construction and the tiles have very small thickness. The firing is essential for a long life cladding. It is, therefore, a sustainable specification choice.

Energy Efficient HVAC System/ Innovative Ventilation System 17 24 Very closely controlled ventilation rates; very low rates in winter to conserve heat; very high rates in Summer to assist cooling; night purging; use of undercroft as precool / preheat passive affect on incoming ventilation air. As close to zero auxiliary energy as possible. Auxiliary Primary energy from Natural Gas heat pump Wind generated grid electricity for auxiliary lighting, motive power etc Installed capacity of auxiliary heating and cooling well above demand likely but ‘safety net’ for client / user comfort during ‘spikes’ in demand

Ventilation System. The offices are naturally ventilated at all times summer and winter using purpose designed trickle ventilators for normal loads and rapid response increased ventilation rates from windows with PV power driven servo motors opening based on intelligence from the BEMS (Building Energy Management System) 18. Stale air rises vertically through the central atrium (assisted by the combined stack effect of buoyancy and wind pressure differential) under normal situations, and exit via the specially designed ‘Venturi’ natural ventilation device at the top of the atrium.

The building is a totally naturally ventilated passive building. The orientation of the facades is strategically directed towards the prevailing winds in Ireland. The building will be in dynamic equilibrium for 8 months of the year and will only use the natural gas heating for heat-up in the mornings and that the building will sustain itself during most of the day with a boost required in the afternoon. Auxiliary cooling, when/ if required will be the obverse. The natural ventilation system is designed to provide passive free-cooling at night time utilising a B.M.S. system to open the relevant motorised louvers / windows / dampers to provide the cool air flow across and up through the building and also utilising the ground floor undercroft pre- cooled chilled air .The roof of the plantroom is covered in photovoltaic cells which feed a battery back and are used via an invertor to drive the motors of the natural ventilation system. The entire ventilation system is naturally driven relying on auxiliary primary energy as back up only. Each individual two person office has a personally regulated trickle vent built into the external window and ingress internal glazing unit, closed, tilted or turned.

Under abnormal conditions (i.e. during summer with negligible wind) a specially designed solar chimney with parabolic cross section is designed to evacuate the stale air and provides a minimum of one air change per hour throughout the building 16 15

Heating/Hot Water. Heat is supplied via two natural gas fired atmospheric condensing boilers for heating the radiators. Hot water is provided by means of a vacuum enhanced solar array on the roof with the system topped up via a similar atmospheric natural gas-condensing boiler.

Water Consumption. A rainwater harvesting system 19 is used to gather water to supply the water to the Toilets in the Building, and will supply 66% of the building water requirements.

The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo)

Day Lighting & Lighting Installation. The Building’s banking hall’s main fenestration has been provided with high level windows to provide deep internal light to the offices. This fenestration has been provided with extensive seasonal deciduous planting on the outside to shade the south and west elevations from solar transmission ratio of 38% whilst maintaining daylight admission to 65%. The lighting system throughout comprised of low energy fluorescent lights using high frequency lamps. The lighting system is controlled by Infra Red sensor technology and set to operate on occupancy of the offices and the desired lux level. Careful attention to lighting layout; banked switching; automatic switching to avoid nugatory use; very low energy lamping. Balancing of heat loads with ventilation /heating regime Cooling. The building utilising the B.M.S. controlled natural ventilation systems will maintain the correct ambient in the building throughout the year. However, a gas-fired heat pump has been installed to provide the installed capacity for auxiliary cooling to deal with any excesses or ‘spikes’ above 24 deg.C or during meetings etc. To enhance the free cooling effect of the Building the undercroft under the Banking Hall has been provided with B.M.S. controlled Natural Ventilation to allow the floor of the Banking Hall to be cooled as in a chiller beam effect. Computational Fluid Dynamic (CFD) Modeling 16 The Building was subjected to three-dimensional CFD (computational fluid dynamics) tests at Strathclyde University to ascertain the effectiveness of the passive ventilation system, particularly as affected by the ‘Venturi’ roof ventilator .We commissioned Dr Jeremy Cockroft and Dechau Tang at the University of Strathclyde to carry out cfd testing of a virtual model of our design; the following images are visualisation of their results which informed some detailed design aspects;

Intelligent Energy Management System 18 TREND system; The BMS monitors the following: Temperature within the Solar chimney: Flow and return temperature to the Solar panel from the HWS system: Main Incoming Gas meter: Main Incoming water meter: Main Incoming Electricity meter (wind derived) : Water tank High/low level:Bazak heat Absorption Machine common fault:Rain Water tank High/low level: Mains Water Booster Fault:Rain Water Harvesting Unit Common Fault: Rain Water Submersible Pump Fault: Solar Panel Power Supply Status: Solar System Demand Low Status: Solar System Failure: Solar Panel Common Fault

Lifestyle and Energy Conservation The staircases have been attractively designed to encourage use in lieu of lift for healthy exercise and reduced energy use. The lift is an ‘eco-elevator’ by Kone20 of relatively low energy consumption. In a town choked with traffic the Credit Union is encouraging a modal split away from the private car by providing very restricted private parking and generous, secure, bicycle-parking facilities attractively designed for both members and staff: Within the building, generous showers, changing and locker facilities acknowledge the needs of staff who opt for this more sustainable and healthy mode of transport, reducing traffic congestion and pollution. In hard edged economic terms the building needs to be, and perceived to be, as having high added value in the process of converting their liquid asset reserves into fixed asset building stock with low actual depreciation in terms of long-life loose-fit and high appreciation in conventional property market terms. In other words there are synergies between these determinants The whole ethos of the Credit Union Movement is within the terms of the sustainable development movement in terms of the three pillars of economy, equity, ecology. The building aims to be attractive, interesting, rewarding in architectural terms and have the quality of fascination. Because the building is for an owner-occupier the logic of life cycle analysis is validated without the need for undue external regulation; the benefits of investment in the building come naturally to the owners, over time. A key point is that the the gestalt / nature of the building, is crucial to the continuing prosperity of the Union, which is quite literally owned by 25,000 members; their affection for the building is important; it needs to be a user friendly, even ‘loveable’, building. Architectural Concept

Toni Morrison has remarked that the best art was political and that one “ought to be able to make it unquestionably political and irrevocably beautiful at the same time.” The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo)

The fundamental formal concept is an implicit simple cube - with the attendant benefits of rectilinear geometry; this cube is then ‘worked’, internally and externally, articulating different elements and functions. The plan is a simple basic grid of 9 squares including a central bay, being a void. This is a profound archetype going back through human culture in many traditions, with a centred, resonant, energy. The relationship with the existing building33 (which we also designed) is via a simple glazed link onto an existing structural opening. The cube orientation is square-on-diagonal with one vertex due south. Irish people perhaps value sunlight more than most, given our often cloudy weather. The orientation of the main spaces to the South responds to this. The main banking hall space opens onto a landscaped peace garden. At higher level the managers office and overhead the canteen / reception room both open out onto a loggia on two levels providing external space for taking lunch outdoors in good weather and a ‘step out’ from the stresses of the working day. This two storey loggia is a spatial cube being set into the parent solid cube. The central void does not just drop down through the building in a banal way but alters laterally to improve sunlight access and provide a visual cascade to the edges of the floor plates, which also have provision for trailing cleansing plants between levels. At the top of this void is the rooflight / ventilator: off this opens a solar chimney device (see above).

This sculpting of the inherent cube continues in the staircases, lift shaft and associated external service ducts which are pulled proud and given distinctive form and colour. The tradition here is of clean volumes seen in space; not an urban street building as such but one which addresses the linear civic space providing closure and a prospect from within the prismatic east stair.

IMPEDIMENTS and how they were overcome The first impediment was procuring planning permission; in fact this took some years! Determination is the only answer to this and slowly the zeitgeist is changing to recognise sustainable building as the way forward. The second major impediment is resistance of the market to change; this leads to gross over pricing of innovation, especially in a buoyant economy, such as Ireland has been experiencing for some years; the ‘sellers market’ tends to amplify convention – subcontractors want to do ‘more of the same ‘ for profit reasons and are resistant to new ideas and bespoke work. Once again we found that determination and careful placing of sections of the work was the answer. Innovation brought its challenges on site; when subcontractors are in unfamiliar territory the coordination becomes a much bigger task as familiar interfaces are no longer to be taken for granted. See Main Contractor’s comments. We chose this main contractor PJ Hegarty, from bids received not on the basis of lowest initial price but on a total profile of quality and a preparedness to take on the challenges of innovation and adopt a partnership approach with the design team. This has worked well on site.

Comments from the Main Contractor “From the outset everybody involved on the site, from management through to the workforce, were aware that they were involved in something quite different to standard Irish construction projects. The cutting edge design, incorporating an extensive design development input from the specialist subcontractors, was a challenge for all involved. The use of non-standard materials, products and methods involved a learning curve for all. The structural timber frame, detail designed in Switzerland and manufactured in Germany, was the first of its kind in Ireland. The erection of the 5 stories was completed in approx 6 weeks. This left us with the challenge of protecting 75% of the building finishes, from a very early stage in the project.”

Art We have been fortunate to find two such sympathetic artists as Rachel Parry 21 and Cormac Boydell 22 who have further embodied the spirit of the building in manifest forms relating to the human figure and creatures in flight, as well as figuration of the two lovely rivers which come together at the town site of Navan, in a piece titled ‘Confluence’.

Acknowledgements I would like to acknowledge all the design team: Sally Starbuck (Project Architect), Kerstin Schmidt, Caoimhín O’Maollalaigh, Derek Kiernan, Deborah Burrows, G&T (QS); David Myers, G&T (QS); Brian McPhillips17; fellow members of GAIA International who gave us general collegiate assistance during the design development of this project in particular architects Joachim Eble23, Dag Roalkvam24 , Bjorn Berge26; on the contracting side - Kevin OBrien Director, Ed Reid Site Manager, et al, in PJ Hegarty & Sons.31 The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo)

References 2 Lovins A. et al : 1998: “FACTOR FOUR: Doubling Wealth- Halving Resource Use” The New Report to the Club of Rome, published by Earthscan ISBN 1 85383 406 8 3 Gima Moeding WWW.Gima-Ziegel.de 4 St Mary’s Navan Credit Union Ltd www.navancu.ie 5 Merkle Holzbau GMBH http://www.projekt-holzbau.de 6 Pirmin Jung, Consulting Engineers Ingenieure für Holzbau GmbH CH - 6026 Rain ; [email protected] www.ideeholz.ch Contact: Jurg Stauffer / Pirmin Jung 7 Clayplaster: Tierrafino: www.tierrafino.com 8 Nordan: www.nordan.co.uk 9 Voltex / Volclay : Colloidal clay damp roofing http://www.cetco.com/bmg/ 10 Earth Born Clay paints: www.earthbornpaints.co.uk 11 Ecocement: from Granulated Blast furnace slag aggregate www.ecocem.ie 12 CTC / Newline Engineering: Strucad Software 13 Lam, Marta ; Ip, Dr K :“Bioshaders for Sustainable Buildings”( CIB T2S4 Special Environmental Design www.brighton.ac.uk/environment/contact/research_students/marta_lam.htm 14 Solar Thermal and Photovoltaic :Energy 365 www.energy365.ie 15 Pensher Skytech; Venturi Ventilator rooflight and Solar chimney www.pensher.co.uk 16 ESRU :Univ. of Strathclyde : CFD modeling www.esru.strath.ac.uk/Consultancy/Ex4_navan/navan.htm 17 Derham McPhillips: Consulting Engineers,(Services) Dublin Ireland ([email protected]) 18 BMS Standard Controls :Trend [email protected] 19 Rainwater harvesting http://www.greenshop.co.uk/ 20 Eco Elevator www.kone.com www.hightechfinland.com/2002/newmaterials-processes/sivu.php 21 [email protected] 22 www.cormacboydell.com 23 Eble Architektur:[[email protected]]Joachim Eble member GAIA International

24 Roalkvam, Dag: 1997 “Naturlig Ventilasjon” av siv ark GAIA LISTA: Member GAIA International

25 Gardiner and Theobald: Quantity Surveyors (www.gardiner.com) 26 Berge, Bjorn: GAIA Lista 2000 Architectural Press ISBN 0 7506 3394 8 “Ecology of Building Materials” member GAIA International 27Hammer, Peter: (editor) 1998 ISBN 0 86282 111 0 “ Acoustic Performance of Medium Rise Timber Buildings” COST Action E5 Workshop 28 IABSE Conference Report: Lahti Finland 2001 ISBN 3 85748 1003 X “Innovative Wooden Structures and Bridges” 29 Oesterle.LIeb.Lutz Heusler Prestel 2001 Double Skin Facades: Integrated Planning: ISBN 3 – 7913 2504 3 30 Dr Howard Morgan, International Fire Consultants www.intfire.com 31 PJHegarty Main Contractor WWW.PJHEGARTY.IE 32 www.bollom.com/fireprotection 33 Plan Magazine Ireland: May 1988: Also ‘Build’ Magazine Ireland March 1988