While steel and concrete construction releases large amounts of carbon into the atmosphere, wood traps and stores carbon. Triple Bottom Line
Mass timber, unlike the wood used in stick-built residential construction, is more fire resistant than steel, with 30% the weight.
1. Cross Laminated Timber (CLT) - Layers of timber (lamellas) glued together with grain alternating at 90 degree angles. SmartLam, with a location in Alabama, was the first commercial Cross Laminated Timber (CLT) manufacturer in the U.S. Their work includes the Tacoma Washington Train Station.
2. Glue Laminated Timber (Glulam) - Larger and longer beams and columns are produced by layering laminates with the grain aligned. Samples by Rubner Holzbau in Europe.
4. Dowel Laminated Timber (DLT) - No glue, no nails, easy reuse. Also called DowelLam and Dübelholz (“Dowelled Wood”).
"DLT panels are made from softwood lumber boards stacked like the boards of NLT, but friction-fit together with hardwood dowels instead of nails. The dowels hold each board side-by-side, forming a stiffer and stronger connection than the nails in NLT. Each board lamination in a DLT panel is finger-jointed, creating a stiffer and stronger panel than NLT as it eliminates the board splices and butt-joints which are characteristic of NLT. DLT panels may be processed using mill machinery, unlike NLT panels due to the nails. This creates a high tolerance panel which can also contain pre-integrated electrical conduit and other service runs." more
Timber and CLT components should be located on a suitable damp proof course membrane (DPC) at a minimum of 150mm above finished ground level unless a solution using an active drainage system is provided to reduce the distance.
In February of 2020 Macy's headquarters announced their move into Georgia's first mass timber office building - T3 West Midtown at Atlantic Station.