Aveline Flooring July 14th, 2017 - 21:02:21
Raw sheathing comes in 4`x8` sheets, most often installed as 3/4" thick plywood panels. This type of sheathing is adequate for spanning joist work spaced up to 24" apart. The sheathing is lain with the joints staggered in such a matter, that no two edge joints line up with adjoining sheets. It is very easy to install, requiring the least amount of labour. The sheets are fastened with either 1-1/2" flooring screws, or 2-1/2" nails, spaced about 8" apart. Although not required, it is a good idea to provide backers or supports under the joints, between sheets which run perpendicular to the framed floor assembly.
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.
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.
The third variable is installation costs. Our engineered product has labor savings over our solid wood product because it is pre-sanded and milled to tighter tolerances. It is also prefilled in the holes and has next to zero waste. On the other hand you may have a little more in cost of gluing it down in addition to nails, but this is just a step in direction of better quality and peace of mind during the install.