Osb comes in 4 by 8 foot sheets as does plywood but the manufacturing process allows the production of longer and wider ones.
Osb thickness flat roof.
Typical types of wood used for roof sheathing are oriented strand board known as osb and plywood the most popular being osb.
Installed correctly allowing falls to roof using per furring.
Flat roof requires maintenance for a small leak in the middle of ceiling.
Current standards also permit swiss krono osb to be used as outer boarding in flat roof constructions.
Double nailed at each joist.
Large rooftops can be realised much more quickly and easily this way than with conventional boarding.
Oriented strand board osb osb is a type of wood panel comprising of timber strands and should be manufactured in accordance with bs en 300.
A minimum thickness of 18mm these will be able to span up to 600mm.
We re in dallas so we don t engineer for tremendous live loads for an asphalt shingle and we feel comfortable with 16 oc rafter spacing and 7 16 osb decking.
Osb a sterling board.
Currently we space rafters 16 oc and use 7 16 osb with h clips.
Most roofs are spaced at least 20 inches apart.
A minimum thickness of 22mm is recommended.
In this case you can t use a 3 8 inch thick sheet.
Impervious to any waters ingress.
However you might find that osb can better suit your needs than plywood for the roof.
With edge support and the same snow load 3 8 inch osb can be used.
Should we replace the entire roof with new materials 9.
Thicknesses range from 5 16 to 3 4 inch and the proper one to use.
Fortunately this is one issue that has primarily been standardized by the industry.
For this you can either go for a half inch or 5 8 inch thick sheet.
Both cdx plywood and osb tend to come in standard sheets of four foot by eight foot 4 8.
Osb roof decking thickness 7 16 1 2 or 5 8.
For the curious 7 16 osb has a span rating of 24 16 and with supports every 24 inches is good for a roof live load of 40 psf pounds per square foot with a 10 psf dead load.
Sheets of 7 16 inch thick with no edge support can be used in an area where the snow load is 30 pounds per square foot.
Laid with staggered joints.
The thickness required by josh s circumstances are good for roof snow loads of up to 70 psf again spanning 24.
Once the spacing hits 24 inches a 5 8 inch thick sheet is more ideal.