Hey gang re doing the roof on my detached garage.
Roof boards vs plywood 05b.
Plywood is an engineered wood from the manufactured boards family which also includes particle board and oriented strand board osb.
As roofing contractors in seattle we are often asked why do we need plywood over our old solid sheathing.
There are always comparisons of plywood to particle board but at the end of the day both are susceptible to.
Since the boards used for shiplap were manufactured here in the pacific northwest it was still cheaper than plywood up through the 1960s.
Snowfall and ice accumulation can affect the load put on a roof.
The minimum plywood for roofing.
For the less standard 20 inch apart rafters plywood with inch or 5 8 th inch thickness can be used.
When sheathing a roof.
It is made from thin sheets of veneer peeled from debarked wood.
My existing fascia board is wood 2 x10 not sure why so large and heavy but that is what it is and the existing soffit is ply.
Osb and plywood come in thicknesses ranging from 5 16 to 3 4 inch and the thickness needed for a particular roof depends on several factors including rafter spacing expected load and roof design.
Both cdx plywood and osb have advantages and disadvantages when it comes to plywood for roofing.
Most western washington residential homes during this time were built with shiplap roof decks rather than plywood.
Rafters run from the peak of the roof.
Is plywood or osb best.
The edges may also swell during this time creating small yet visible ridges on the roof where the boards meet.
The ability of plywood to return to shape after wetting makes it a lot less risky in this application and while a little more expensive that s still cheaper than having to replace a floor.
However 3 4 th inch plywood is also used for a roofing system that has a heavier load.
These 8 to 12 inch wide boards were nailed together tight.
This carries enough structural integrity for most roof loads.
Why re sheet over shiplap.
My soffits and fascia board need to be replaced what do you recommend wood or hardie plank.
At the end of the day what kind of plywood should you use for your roof.
Until the 1940s exterior grade plywood was not available.
Contractors often prefer to use osb because of the significant.
These thin layers also called plies are glued together in alternating right angles to create a cross grain pattern.
In an ideal world you would schedule your roof construction during a dry period if possible.
The keyword here is solid it used to be standard to use shiplap 1 boards tongue groove or other boards for the roof deck.