I N D U S T R Y N E W S 12 West Virginia Forestry Association Mountain State Forestry | Fall 2018 www.wvfa.org Capability CLT is typically used for floor, roof, and wall elements of building structures with spanning capabilities of up to 8m or up to 12m when used compositely with concrete or as a fabricated cassette section. CLT has high in-plane strength and stiffness, which also allow it to be used effectively as shear walls, diaphragm plates and deep beams. Quality CLT is manufactured to strict QA requirements from stress graded timber of known structural capacity. Stability CLT is manufactured from kiln-dried timber (12% moisture content) and the cross-lamination process makes it less prone to movement caused by changes in moisture content. The report used two detailed exemplar cost models, one each for a CLT and concrete design for a seven-story private residential building. The scheme has been designed with both a timber and concrete solution in mind at the outset, for ease of comparison, with a structural layout to suit both. The cost model is based on: A building in London (Zones 3–6) 307,912ft² gross internal floor area / 223,286ft² net internal (residential) area A small retail shell at ground level 294 residential apartments (all for private sale) CLT frame, upper floors, roof, core, stairs, external walls (all first floor and above) Reinforced concrete ground and transfer slab CLT all non-visual grade Piled foundations due to poor ground conditions All rates are base dated at Q2 2017 and reflect a two-stage competitive design and build tender. Exclusions from the cost model include demolitions, fees (professional and pre- construction), external works, incoming utilities, section 106/278 agreements, and VAT. Authored by Alex Hyams, Steve Watts and Catherine Harvatt at Alinea Consulting, with assistance from Paul Grimes and Clive Fussell of Engenuiti, and Danny Hopkin of Olsson Fire & Risk.