Nail-laminated timber (NLT or nail-lam) is a century-old construction material that is undergoing a design renaissance. Its structural performance and design elegance come together to create inspiring spaces in many historical buildings as well as modern new projects of all sizes.
To create NLT, dimension lumber is placed on edge with individual laminations mechanically fastened together with nails or screws. The boards are nominal 2x, 3x, and 4x thickness. Width is typically 4-12 inches. NLT gets its strength and durability from the nails/screws that fasten individual pieces of dimensional lumber into a single structural element.
NLT’s revival is due in large part to domestic availability. The mass timber product does not require a dedicated manufacturing facility—compared with other building materials like cross-laminated timber (CLT)—and it can be fabricated with readily available dimensional lumber. This allows project teams and manufacturers to use locally sourced materials.
Applications for NLT include flooring, decking, roofing, and walls, as well as elevator and stair shafts. Because NLT is made of wood, it offers a consistent and attractive appearance for decorative or exposed-to-view applications.The International Building Code (IBC) recognizes NLT as code-compliant for buildings with varying heights, areas, and occupancies, allowing for Type III, Type IV, or Type V construction.
Architects like NLT because it can be used to create monolithic slab panels that support a range of structural and design needs, including curves and cantilevers. The addition of plywood or oriented strand board sheathing on one face of the panel provides in-plane shear capacity, allowing NLT to be used as a shear wall or structural diaphragm.
Its exposed wood ceilings add aesthetic warmth while absorbing noise. Floors are topped with reinforced concrete for added durability.