Nail Laminated Timber – NLT

Overview

NLT (Nail Laminated Timber) is a mass timber panel system which can be used for floor, wall, and roof structures. Tall wood buildings like T3 Minneapolis have used NLT as floor and roof panels atop Glulam beams.

Dowel laminated timber (DLT) offers automated production of all-wood panels. NLT may suit projects that call for specific freeform or warped panel geometries.

Nail-lam floor and wall assemblies have been used for more than a century, particularly in warehouses where solid, sturdy floors were required. It is now being recognized again as a valid substitute for concrete slabs and steel decking in commercial and institutional buildings, and residential buildings in which it is often exposed to create a unique aesthetic. In addition to being used in floors, decks and roofs, mass timber panels are now often used for the timber elevator and stair shafts in six-storey, light-wood frame residential mid-rise apartment buildings.

NLT is created from dimensional lumber stacked on edge - 2x4, 2x6, 2x8, 2x10, or 2x12 at 1-1/2" on center - and fastened together with nails. Plywood sheathing is often added to one top side to provide a structural diaphragm. Plywood sheathing also allows the product to be used as a wall panel element.

In much the same way as tongue-and-groove wood decking, NLT is sanctioned by building codes in both Canada and the USA (NBCC and the IBC). NLT qualifies as Heavy Timber as long as it is "well-spiked together" and the depth is at least 64mm for a roof and 89mm for a floor (see NBCC 3.1.4.6 4b/6b and IBC 602.4.6.1). As such, it does not require an "alternative solution" application.

Our involvement

StructureCraft engineers and integrates NLT where its structural system and geometry suit the project.