Published at Wednesday, 02 August 2017 by Solaina in Flooring, with total 25 digitals.
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.
There are three main types of sub-flooring installed to cover and span the floor structure. It is over this that the finished floor will be placed. The sub-flooring types include raw sheathing, interlocking and strip. It is utilized not only to provide a surface for the interior finishes to be placed on, but also to prevent twisting or torque forces placed on the building. The sub-floor also allows load sharing within the joist framing system. Often the sub-flooring is glued to the joist work to eliminate creaking floors and to prevent the floor joists from turning.
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.