What is the best plywood to use for roofing?
CDX is the grade of plywood most commonly used for roofing (CDX plywood means it is Construction Grade for exterior purposes). The wood is graded on each side from A to D, depending on the level of imperfections, (A being free of all imperfections and knots and D being un-sanded and considerably defected).
Is OSB better than plywood for roofing?
OSB takes longer than plywood to get saturated, but also takes much longer to dry out. When used as roof sheathing, this tendency to hold moisture means it will degrade faster than plywood when exposed to chronic leaks.
Do you use treated plywood for roofs?
Contractors generally recommend treated plywood rather than regular plywood for roof decking because condensation can build up on the sheathing and cause rot. Roofers understand that when it comes to the roof deck, the amount of water that gets on the wood is a concern.
What type of wood should I use for roofing?
Oriented strand board (OSB) – OSB is the most common type of material used for roof decking. It’s durable and readily available, and has relatively low costs. OSB is made of interwoven strands of wood bonded with adhesive.
Can CDX plywood be used for roofing?
Only use CDX plywood for the interior of a house, where water damage is far less likely. Do not use CDX for roofing, sheds, or other places that are exposed to moisture consistently. The sole exception to this is pressure treated CDX, which can survive for decades without even a protective coating.
How much is a sheet of plywood for roofing?
Your price could vary depending on how much the roofing company charges for labor, but generally, you can expect to spend between $70 to $100 for each sheet of plywood. A 4 x 8 sheet of plywood covers about 32 square feet of roof area—and the average roof measures about 3,000 square feet.
What thickness plywood is used for roofing?
Most roofs will be sheathed in plywood at least 3/8 inch thick. That will suffice on a roof with rafters set 16 inches apart with minimal roof loads.
Which is stronger OSB or plywood?
Osb is stronger than plywood in shear. Shear values, through its thickness, are about 2 times greater than plywood. This is one of the reasons osb is used for webs of wooden I-joists.
What thickness OSB should be used for roofing?
If you are using OSB for your roof deck, then ⅝” is the recommended thickness. For plywood, which is slightly stronger than strand board, ½” thick is appropriate.
How much is a sheet of OSB plywood?
OSB (Oriented Strand Board) Prices
|in Inches||in MM (rounded)||Price per Sheet|
|1/4″||6||$15 – $20|
|7/16″||11||$20 – $25|
|1/2″||13||$21 – $28|
|23/32″||18||$26 – $32|
Do I need pressure treated plywood for shed roof?
Ordinary exterior-grade plywood is made with weather-resistant glue, but the wood itself is not particularly rot resistant. This is why pressure-treated plywood is best for a shed floor. Even a floor that’s raised off the ground a bit will last longer if it’s made with pressure-treated plywood.
Do I need pressure treated wood for roof?
As long as there’s a good chance that moisture can reach the wood, it should be pressure treated. This is why the International Building Code requires that siding and structural lumber used for the last six inches of the structure above the ground is pressure treated.
Is 7/16 OSB OK for roofing?
…or a non-laminated panel, such as this OSB. Either one is acceptable. The typical thickness of roof sheathing is about 7/16-inch, which is just under 1/2-inch. … If you find 3/8-inch plywood installed as roof sheathing, it’s a good idea to make your client aware of its presence.
What kind of wood do you use for roof rafters?
Kiln-dried Douglas fir wood presents the number one choice for building a rafter-styled roof in a wood frame house.
What size wood do you use for rafters?
Max. Live Load 20 lbs/ft2 (956 N/m2)
|Maximum Span (ft – in)|
|Nominal Size (inches)||Rafter Spacing, Center to Center, OC (inches)||Lumber Grade|
|2 x 10||16||25′|
|24||20′ – 9”|
|2 x 12||12||33′ – 6”|