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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 is the standard plywood for roofing?
Most Common Thickness The most common rafter spacing is 24 inches, and 5/8-inch plywood is recommended for that. It will support roof loads for most situations and is the standard for most roof applications. Roofs with very heavy loads may require 3/4-inch thickness.
What grade of plywood is used for roof sheathing?
1/2 or 3/4-inch Plywood for Roof Sheathing? – Traditionally, 1/2-in CDX plywood was common choice with 24-in rafter spacing. However, heavier roof loads may require the use of 3/4-in CDX plywood for roof sheathing. Roofs with less pitch often carry heavier loads, including snow and ice accumulations in the winter.
What kind of plywood do you use for a shed roof?
Most builders use 15/32 CDX for the roof; it is an exterior-grade plywood with a thickness just under 1/2 inch. The floor needs to be more solid than the roof to support lawn maintenance equipment and people. Use sturdy, 3/4-inch-thick exterior plywood for the floor.
What is better for roofing OSB or plywood?
Plywood Holds the Moisture Advantage Over OSB When plywood gets wet, it tends to swell. 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.
What type of wood should be used 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.
How thick should plywood be for a shed roof?
Plywood thicknesses for roofs start at 3/8” in areas with light load requirements on rafters at 16” centers. Thicknesses of 1/2 to 5/8 inch are common with rafters spaced at 24” centers. For heavy load rated areas, 3/4-inch-thick plywood is recommended, regardless of rafter spacing.
How much is a sheet of roofing plywood?
The thicker the plywood your roofer uses, the more expensive the job will be. 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.
What thickness OSB should be used for roofing?
Standard roof sheathing thickness is ½” to ⅝” thick. 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. Another factor is how far apart your trusses or rafters are spaced.
Is CDX plywood good for roof sheathing?
Moisture Differences In reality, CDX plywood can only withstand water for a short period of time. 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.
Can you put new plywood over old on a 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.
What is the minimum thickness of roof sheathing?
Sheathing must be a minimum of 19/32-inch thick. Never affix roof sheathing with staples; 8d ring-shank nails need to be used instead. The normal thickness range for sheathing is 3/8 to 3/4 inch.
What is RTD plywood used for?
Exterior panels sometimes referred to as RTD sheathing, are designed to hold up to constant moisture. They are completely waterproof and are great for installing in places where you expect consistent exposure to moisture. This RTD sheathing is great for roofs and other outdoor applications.
What is the best way to waterproof plywood?
Yes, you can make plywood waterproof by spraying it with liquid latex, waterproof paint, or varnish. You can also coat it with epoxy sealant or hard-drying oil to seal it and make it impervious to water.5 days ago.
What is the best wood for a shed roof?
thick plywood works well for wall and roof sheathing, but use at least five-eighths in. plywood for your shed floor. 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.
Which is cheaper plywood or OSB?
OSB is less expensive than plywood. To build a typical 2,400-square foot home, OSB may cost $700 less than plywood. OSB is considered by many to be a “green” building material because it can be made from smaller-diameter trees, such as poplars, that are often farmed.
Do you need H clips roof sheathing?
H-clips are referred to in the APA Guide as “edge support.” For the most common roof sheathing in our area, which is 1/2” nominal (7/16” actual) sheathing over trusses or rafters at 24” on center, there is no requirement for H-clips. One or two H-clips will often allow a longer span between roof trusses/rafters.
Can I use pressure treated wood for roof rafters?
Answer: Whether pressure-treated lumber is appropriate for trusses depends on the preservative used in the treatment process. If the lumber treated with waterborne preservatives is kiln dried after treatment, most of the preservative chemicals are inert and normal plates can be used.
