As long as the interior of your roof is protected from moisture accumulation, underlayment is not required, though homeowners planning to insulate their house heavily may choose to install plywood to protect their investment.
Is roof sheathing necessary?
Your roof sheathing is an important component of your roofing system. Sheathing holds up your shingles, keeps the elements out, and helps distribute weight evenly across your roof.
Does new roof include plywood?
If you are getting a new roof, while you may not necessarily need to have the plywood decking replaced, you should have it carefully inspected by a qualified roofing contractor. … When considering a contractor for your project, be sure to address the subject of plywood replacement, and what the cost per plank will be.
Is plywood required under shingles?
Over the years, plywood replaced boards, and oriented strand board, or OSB, has gradually replaced plywood. Typically, older homes were originally roofed with wood shakes or shingles. … When the original wood shakes or shingles failed, they were typically replaced with asphalt shingles, which require solid sheathing.
What type of wood is used for roofs?
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.
What is the best roof sheathing?
OSB is now the most-used sheathing and subflooring material for new roofs and roof replacements. OSB is currently selling for less than plywood by approximately $3 per sheet, meaning a savings of several hundred dollars per conventional home.
Should plywood go under metal roof?
For many applications, a layer of plywood underneath your metal roofing is an unnecessary expense. … Boards measuring 1 inches by 4 inches or 2 inches by 4 inches are commonly used for purlins, though never use treated lumber because it will corrode the steel roof and fasteners.
Which plywood is best for roofing?
Exterior Plywood is the preferred material for roofing. It also performs well when exposed to moisture over long periods of time. The price is low compared to other roofing materials and the installations are also easy.
What type of plywood is best 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).
Can you put plywood over plywood on roof?
The new plywood will have to be nailed to the rafters or roof trusses. … But, with the old plywood left in place, it will be considerably more difficult to locate the rafters to ensure proper nail placement.
How much plywood do I need for a roof?
Divide the total roof area by 32 to get the number of sheets you will need to cover the roof. A typical 4 foot by 8 foot sheet of plywood covers 32 square feet. If your roof area is 1,600 square feet, 1,600 divided by 32 will mean you need about 50 sheets to cover the roof.
How much does it cost to replace plywood on a roof?
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.
How long does roof plywood last?
How long does roof plywood last? As plywood lasts about 30 to 40 years and we run the risk of delamination and required replacement in a few years.