Building Enclosures for 5&6 Storey Mid-rise Buildings Lessons Learned & Best Practices MID-RISE WOOD-FRAME WORKSHOP, CALGARY - FEBRUARY 4, 2016 GRAHAM FINCH, MASC, P.ENG PRINCIPAL, RDH BUILDING SCIENCE GFINCH@RDH.COM - 604-873-1181 Presentation Outline 7 Background why taller wood? 7 5&6 storey wood-frame building enclosure best practices & lessons learned 7 Wood framing, energy codes & additional insulation 7 Considerations & detailing for woodframe shrinkage 7 Balcony design trends 7 LUNCH BREAK 7 Water management & claddings 7 Air barrier strategies & materials 7 Maintenance & renewals planning 7 Reference guides & resources G.Finch - RDH - gfinch@rdh.com 1
Recent History of Mid-Rise Wood Buildings in Canada 7 Pre 1900 many examples of mid-rise wood buildings up to ~10 storeys still around today 7 Mid 1900s national building/fire codes were introduced limited wood-buildings to 3-4 storeys 7 Mid 1990s to early 2000s, Washington & Oregon States begin to allow construction of 5 storeys wood frame over concrete podium ( 5 over 1 ) 7 2009 BC allows 5&6 storey wood-frame 7 Over 250 buildings planned, under construction or built in BC to date 7 2013 Quebec allows 5&6 storey wood-frame 7 2015 Ontario allows 5&6 storey wood-frame 7 May 2015 Alberta allows 5&6 storey woodframe with adoption of 2015 NBC allowances 1900s era Tall Wood Buildings AcrossCanada 2014 - WoodInnovation Design Centre,BC A Number of Recent Code Changes in Alberta 7 As of May 1 st, 2015 the new Alberta Building Code has allowed for wood-frame buildings up to 6 stories G.Finch - RDH - gfinch@rdh.com 2
Drivers for Larger & Taller Wood Buildings 7 Recent industry interest, research and pilot projects to advance construction of 5&6 storey and even taller wood buildings 7 Several Canadian efforts and initiatives 7 Changes to building codes, allowance for alternate solutions with more wood 7 BC Wood First Act 7 Tall Wood Study & Tall Wood Guides (FP) 7 Carbon sequestration (carbon sink of wood vs. carbon source for steel or concrete structures) 7 Sustainable & Renewable Resource 7 Aesthetics & Architectural Considerations 7 Speed of Construction, Cost Worldwide Tall Mass Timber Buildings 8 storeys LCT One, Austria, HermannKaufmann 9 storeys MelbourneAustralia, LandLease 8 storeys Finland, OOPEAA 14 storeys, Treet Norway, Artec 9 storeys Murray Grove, UK, Waugh ThistletonArchitects Many Similarities: - Mass Timber Components, CLT, Glulams etc. - Pre-fabricated components (walls, floor panels) - Hybrid wood & concrete structures G.Finch - RDH - gfinch@rdh.com 3
Emerging Trends - Taller Wood in North America 12 storey wood, Portland OR (in design) ~100ft wood, Prince George, BC Wood Innovation Design Centre 18 storey wood, Vancouver, BC 10 storey wood, New York (in design) Mid-rise Wood-frame Building Enclosure Trends G.Finch - RDH - gfinch@rdh.com 4
Building Enclosures for 5&6 Storey What is Different? 7 Taller buildings = increased exposure to wind and rain 7 Need for better site protection, use of more robust assemblies and materials including roofing, claddings & windows, consideration of pre-fab 7 More structural framing 7 Less space for insulation within studs 7 Unique wood/steel/concrete interfaces and details to consider 7 Non-combustible claddings & enhanced fire-safety considerations during construction & in-service 7 Different energy code requirements than 3&4 storey & Part 9 wood-frame Building Enclosures for 5&6 Storey Trends 7 More than decade of experience with 5&6 storey wood-frame buildings on the west coast (BC, WA, OR) 7 Continuous progression of building enclosure practices resulting from: 7 Building code changes including WA State requirements for whole building air-tightness testing 7 Energy code changes pushing minimum wall R- values beyond 2x6 studs w/ batt insulation 7 Pre-fabrication of walls, balconies and other components to speed-up construction 7 Unique details to accommodate or minimize the impacts of wood shrinkage 7 Reconsidered material, assembly, & detailing choices appropriate for increased exposure G.Finch - RDH - gfinch@rdh.com 5
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And When It Isn t Challenging Enough on Land Wood Framing, Energy Codes & Mid-Rise Wood Buildings G.Finch - RDH - gfinch@rdh.com 7