Nynette Flooring August 07th, 2017 - 18:19:16
Truss floors are simply that. They are constructed from small dimensioned lumber, interconnected in a webwork pattern by the use of metal or wood plates. Occasionally, the trusses will be built on site, utilizing plywood plates to connect the webwork together. Generally they are installed 24" apart, either suspended on bearing walls or beams, or installed with plywood trim or rim joists around the perimeter. Strapping is installed on the bottom side, to prevent turning in place, which is a common ailment for deep truss components.
In the case of long span truss work, bearing lengths of at least 3" are quite common. Trusses span greater distances than framed floor assemblies and can be designed to span the entire building, eliminating center load bearing supports. They are moderately more expensive than framed floor assemblies, but provide a remarkably strong floor with little deflection or "bounce" to it. Another advantage to this type of structural system, is that utility installations can be run between the webwork components. Never allow trades to cut or drill into the members of a truss, for they are manufactured precisely for the loading conditions they will undergo during the life of the building.
In this article we will be discussing several different categories of wood flooring. Solid wood flooring is one board with no glued up laminations; it is basically wood board that has been sized and profiled to a certain dimension. Engineered flooring has a on the top whatever species and texture you want, and this is glued to a plywood backer on the bottom. Engineered is still all wood but is made with multiple layers that are laminated for better stability and dimensional accuracy. Floors that we will not cover here are laminates or any composite products which are often not wood entirely through the plank or may be made with a photo printed surface. We also will not cover vinyl, carpet, stone, or tile.
One drawback is that this type of floor requires special hanger systems designed for the joists, to enable them to be hung from each other or against beams/bearing walls. Manufactured joists are becoming a popular flooring system, for they are relatively cheap, reduce labour time and provide adequate support. However, builders need to familiarize themselves with its installations, for poor installation can cause severe structural damage to the joists. A good example is a three point, center bearing joist, left with the top chord uncut, which can potentially fail or pull apart, over the center bearing point.