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

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

THE PROJECTS VISITED

1. THE CARDBOARD HOUSEArchitect 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 furtherin in the winter)- then the U-value of the wall is 0. U-value 0,2, but overall 0,12 dueto this. – a kind of air curtain. A wall with 0,1 is usually 40cm thick, this one is28cm. (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 clearspan 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 regulatehumidity.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 FACTORYAndreas Kempf, www.sohm-holzbau.at40 employees, also does ordinary timber workCost E80,000 for machine, new one costs three times more (not yet mounted)Up to 16m long, 580-620cm broad, 8-30cm thick produce 8000m3 per year, of which6000 DD, 15% sold, rest used in own projects. Cost E500 per cu.m. S10 woodquality, 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 glueing12RH wood and 7%RF dowels. Dowels 20mm diameter, rammede in at 150 barpressure.. At 15 degree angle., double layered. Even wood movement, no bigcracks/gaps can developDrying time of glue?Stress after 3 days.The local timber is not stamped, only the packaged type has been machine tested: anissue of ceetification if export?

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

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On concrete basement. 9cm walls + 3cm insulation + 9cm. Slab 12-14cm.Also: presentation about traditional shingle facades. Local larch – 80 year life – mustbe 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 SCHOOLHistorical project and local pride – avalanche in 1953 killed about 60 villagers, forestplanted, now harvested for these buildings. Tiny school, for about 10 kids, niceindoor space, warm atmosphere and good daylighting.Diagonal. 42cm of massive wood, curious - no insulation. 8cm horizontal, 22vertical, 8 horizontal. Roof 24cm massive wood plus 12cm insulation. School:bounce in the floor (okay!)Local sheep wool feltBeech load bearing compression plates at top of columnsKey process – local timer, local artisans, local history, show their skills.School produced by Sohm

5. NEW HOUSE ABOVE BATSCHUNSNext to Baumschlager artist studioPassive house. E250,000. Massive wood with earth paint with rough finish. On just 8concrete pillars, Triple glass U=0,6. 6,2 metres wide. 6 hours mounting time for themassive wood elements. Heat pump with ground air system. (ca 18cm pipe, 25-30mlength, 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 (at50Pa).. WU asks for 0,5 in his contractSuper 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 saysBirger.

6. BATSCHUNS PASSIVE ROW HOUSESGroup 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 densityissue . 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 roomgeometryAnthracite 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 everyhouse.Wheelchair ramps.Very special kitchen furnishing, storage maximising!All details drawn by WU down to the last thing!

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7. WALTER’S LECTUREInspiration from traditions. And seeing the qualities in “poor” architecture, whichmuch so-called rich architecture often doesn’t have. Simplicity.Importance of understanding and designing the ageing of buildings.Finnish prefabrication 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 howmany green points a building gets. And 50% subsidy for conversion from fossil towood heating.County laws are all different.A wall section: cladding on battens fixed to the stiff insulation mats – 30 cminsulation .- moisture-open barrier – loadbearing zone 10cm with insulation andelectrics – interior panels.

8. TEXTILE FAÇADE HOUSECow shed textile costs E4 per sq.m, material??, 80% airtight. Usually made 100 x 2mrolls, making the house was a tailoring type job. 3 colours were available. Black waschosen.Culvert pipe 20cm, polyethylene, 25m long, at least 1,2 metres deep, 40cm sandaround 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 insmall pipes.Interior walls: 3cm earth panels 1,2 metres long, and earth plaster. (no straw but flaxfibres)Windows: 0,5 glass whole windows 0.8, maximum size 2,5 metres dimension, lightframes. Glass emissivity: low e-factorAir to heat exchanger: ceiling inlet in living room, outtake in kitchenWood burner, 22 sq.m roof PVs.22mm massive wood becech floorWall: from outside: textile on battens, OSB board,40cm cellulose, 4 wood, 3 flaxand electrics, earth board.

9. HOLZBAU LOT FACTORYHappy 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. “Livingboard”Radiant ceiling panelsModular, 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 sideGood for parties! Drive through.

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

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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. Cheapesteverything, but people are asking him for houses like this!Roof also massive wood, with sound absorbing profile of 12mm channels which alsotake electric wiring. Rainwater siphoning system – in case the normal runoff doesn’tfunction. Floor slab is insulated under.Play areas, tree, nice door surround detail.Massive wood with orthogonal dowels (even pallets used as verandah, see the floorcracks), all cheap materials, rough surfaces, texture nice. White pine.Many of WU’s buildings are very reasonable costs. Simplification is a key, but then afew high quality details. Understanding of materials and structure.

11. OELZBUNDT HOUSINGApartment block. architect Kaufman, early project, culvert intake only 2m high, toolow 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 manywere 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 CONSTRUCTION SITE, TSCHOPPSurprisingly poor site health and safety! But good skills levels, all seemed to knowwhat they were doing!Composite brettstapel and concrete floors. Too many layers! Attractive finishedceiling, with acoustic profiling.Some steel too, clad in plasterboard.Weight saving saves foundation costs … but again they must add weight to solve theacoustics 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 time2-3 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 HOLZBAUHochdorf. Ivan Tschopp after father.Brettstapel is one of three divisions. Timber - Interiors - Bresta17,000 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 machines. Direct from CAD to machine shops. Good quality workingand effective machines setup.Showroom upstairs with sectional models etc.TQM quality teams.

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

14. PIRMIN JUNG LECTUREwww.cadwork.ch110m covered bridge designed in 1780 … focus on craftsmenShowed a series of projects and how he contributed to developing new timbersolutions, worked with Natterer and Tschopp. He started dowelling, invented theconcrete-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 FACTORY100 houses per year, more bigger buildings now.Average age workforce 36 years, 120 people. Also a family dynastyFrom 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 hardwoods, etc.Timber from Germany, others.1,0 glass, 2 month building time, 22cm insulation for MinergiePrices E490,000 to 600,000 180sq.m Often cellars. E2,700 per sq.m4 articulated lorries per house.Thinks not much future for brettstapel in walls.

16. LYSSArchitects Itten and Brechbuhl.Forest Training Centre. Alan Kocher director. Great!Very legible building. Opened 1998. A Foundation, owned by 11 cantons. Was to beconrete, previous director insisted on wood. Timber industry is on a decline. Theyalso 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 about1300cu.m per year but in fact they only use about 650.Land costs are extremely high, can be 85-500SFR per sq.m.Foundations: swampyarea, 320 friction piles, due to lighter weight of a timber building their length couldbe reduced by 4-5 metres.Columns – 11 metres, 300, local, 3 cuts, compression tested up to 100tons but theirload is only 40. Abies alba, silver fir. No sticky sap, and 10% cheaper than Norwayspruce. Steel consoles.Floor construction: suspended MDF acoustic ceilings below rough roundpole, thenplanks, 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 about1,7 hours).4 degree slope roof was preferred to required flat roof.

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4 escape routes in each class, fire regs, 4 requiremetns: compartments, doors.,concrete crosswalls, sprinklers, escapeways and ladders; then wood stairs wereallowed too.15-17 degree unheated corridors (semiclimatised)Four student hostel sections, set transversally, duplexes, nice. Solar hot water. Blacksolar shading curtains come down inside the glass and timber ledges along thefacades. 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 parquetfloors.Design goals: reasonable costs – sustainable materials – no luxury – lowmaintenance.Floor construction including round pole.

17. BIEL-BIENNEEngineer 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 verystrong, impressive building, but many things maybe not quite successful. Some of usdidn’t like it.Useful video showing the construction process..Concrete core, timber prefab cells, 10m deep, on each side. Concrete stairwells withglass 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, unclearentrance (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!!

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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 LiddellGaia Group

The MonasteryHart Street Lane

EdinburghEH1 3RG

00 44 131 557 9191architects@gaiagroup.org

www.gaiagroup.org

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Birge Sandy Willi Bernard JohnWhatlearnt

• Engineeringis OK and not

difficult• industrial

spying

• Conversionin relation to

Egan andwant to wipemy desk and

develop aprefab factory

• eye opener• contacts and

network

• need tomove to

prefabricatedapproach

• confirmedfears about

costs oftooling up

• Inspirationallearning

opportunity• new

appreciationopf modernarchitecture

Whatchange

• convincecustomer

• do a projectto

demonstrateand changeproduction

after

• fire, energyregs

• revisit futureproofing

discussion re-flexible design

• fiscalincentives

• integrateexamples into

CPDpublicationand maybe

green guide

• incentivisingminergihouses

• mass timberlonger terms

• needprefabrication

and buildingintegrity• try todevelop

simpler ????• develop eco-house market

• simplifydesigns to

bring downcost

• narrowminded

approach todesign •

attention todetail

How • build aproject (slow)

• Needknowledgefrom pilot

project• do it myself

• publicationsand lectures -specialist littlepublication for

the web?• update the

regulationsreport to

integrate theabove - run

seminar?• build ourown stuff• not just

housing• more tours

• buildingcontrol

officers (CIC)• Look to

research inmodellingculverts,acoustictransfer,

thermal/air/moisture issues,

compressionresistance,

slippage

• need to findout more

• badgering

• import aready made

building• build

something inbrettstapel

• look forcleints for

moremodernistbuildings

• form thescottish flat

roof/ecominimalist

society

• showpictures

• put detailsheets andpictures on

website

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Catriona ESA Juarma Howard Chris

Whatlearnt

• good mix ofgroup

experience

Knowledge ofbrettstapel

• See howbrettstapl has

developedfrom early

days• Similarvalues in

Austria andFinland

• Conversionto pre-fab –

speed andefficiencyimportant

• Fireregulations –

test and show• Specificopps for

brettstapel –not ubiquitous

• Value formoney of

passivehouses and

veryreinforcing

• Shows valueof study tours• importance

of pilotprojects

Whatchange

"can do"attitude •

build onexisting •

adding a newoption

Attitudes toBrettstapel

How challengeecological

assumpotionthat you need

to minimiseamount of

wood

Change1.

Fabrication2. Fire

3. Energy

How • talk todirector

•dissemination

of tour • goingfor demo

project in oneplace • getpeople in the

industryinterested

• a targetedgroup (need

more technicalinformation)• raise at x-party groupbecause ofinterest inaffordable

housing.

Own researchand

advice/discussion with

indudtry of130 wood

productproducers

• Need goodexamples with

goodinformation

• Includetimber ????

Identifyexisting

companies ,build on

people whohave skills –not reinvent

wheel. •Start fire regsdebate Learn

from here –what did they

do to getthem changed

• Exemplarprojects in my

work• Case study

in minergiestandard and

passivestandard

• need topersuade

planners andpoliticians• need to

respect howwe got here