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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 7/16 OSB OK for roofing?
Standard types of wood designed for roof sheathing are oriented strand board, known as OSB, and plywood, the most popular being OSB. Sheets of 7/16-inch thick, without edge support, can be used in an area where the snow load is 30 pounds per square foot.
What size sheathing should be 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. Loads will vary with the pitch of the roof; the flatter the roof, the greater the load on any one section. Steeper roofs will have lighter loads per square foot.
What thickness OSB for a flat roof?
Only OSB/3 or OSB/4 (BS EN 300) should be used in flat roofs. Check that the product has a certificate from the British Board of Agrément (BBA) before agreeing to its use. Thickness: minimum 18mm is recommended.
What is minimum roof sheathing thickness?
For new construction, the roof decking shall be minimum 11 mm (7/16”) thick O.S.B. or minimum 12.7 mm (1/2”) thick plywood sheathing. When reroofing, plywood or O.S.B. roof sheathing shall be minimum 10 mm (3/8”) thick.
Which side of OSB goes down?
OSB also has stamping that reads “This Side Down”. This directs the worker on the correct orientation of the board when installing. The side with the stamp is the smoother side. When installed smooth side down, the rough surface will then face up and give the worker traction for safety.
Can 7/16 OSB span 24 inches?
Wall panels 7/16 Category may be used on studs spaced up to 24” o.c. LP OSB sheathing panels are designed for use in roof, wall and subfloor systems in commercial and residential projects, maintenance, remodeling or new construction. OSB sheathing panels comply with the following industry standards and certifications.
Should you use tongue and groove OSB for roof sheathing?
Tongue & Groove Boards T&G roof decking, however, looks classy and rich. In fact, T&G boards are most frequently used when the sheathing is visible from the inside such as in cathedral ceilings or in some cabin-style homes, especially if the span of the rafters is greater than 2 feet.
How thick should sheathing be?
The U.S. Department of Energy has determined that 7/16-inch sheathing is the minimum appropriate thickness for structural wall sheathing with an exception for gable end walls, where the minimum thickness is 3/8 inch.
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.
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.
Do you nail or screw OSB board?
Tools for Hanging OSB A hammer and 8d nails are standard for installing OSB, but you can speed up the installation by using a nail gun. If the force of the nail gun is too strong, the head of the nail can penetrate the OSB, which reduces the nail’s holding power.
What is 9mm OSB used for?
OSB Board | 9mm OSB can be used for both flat and pitched roofing projects and works well for sheathing in walls. The BBA classification permits use in a wide range of applications such as roofing and flooring in both commercial and domestic situations.
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.
Is OSB OK for shed roof?
For an inexpensive, value option 9mm OSB can be used for your garden shed roof. Start by fitting the beam across the top of the shed, slotting it into the pre-cut grooves at the top of the two pointed ends on an apex shed (known as the gable ends).
How far should roof rafters be apart?
But they do tend to space rafters in one of several industry-standard increments, typically either 12, 16 or 24 inches apart. These spacing intervals are measured “on center,” meaning that the measurement is taken from the center of one rafter’s horizontal surface to the center of the next rafter.
Will screws hold in OSB?
OSB will easily hold screws supporting jigs, misc tools, pegboard, etc. Most things I hang on the walls are a few pounds or less, which OSB easily supports. I try to screw into studs if hanging heavy objects like lumber racks, cabinets, etc. OSB has worked fine for my needs.
Can you use screws on OSB?
You only need a #8 wood screw that is 1 1/2 inches long for 5/8 inch OSB or at most 2 inches long for 3/4 inch plywood. Also, deck screws have a coating that helps protect the screw from exterior exposure, which is not needed indoors. Deck screws will also cost more than the screws needed for your subflooring.
What is the difference between 1 2 and 7/16 OSB?
It depends on where you live. 7/16 is generally considered the absolute minimum where rafters/trusses are spaced 24″ O.C. Around here, 1/2″ isn’t common, or even stocked at the lumber yard. Heavier architectural shingles will make thinner OSB sag between trusses, but will also help hide the unevenness.
What does OSB 24 16 mean?
The span rating on SHEATHING SPAN panels appears as two numbers separated by a slash (e.g., 32/16 or 48/24). The first number is the maximum on center (o.c.) support spacing in inches for roof sheathing. The second number is the maximum o.c. support spacing when the panel is used for subflooring.
Why is OSB painted green?
A story on green building in Saturday’s Home & Real Estate section states that it is a green product because it conserves forest resources by using wood chips that otherwise would be wasted. “The production process uses a maximum amount of wood fiber from each tree harvested, making better use of our forest resources.”Jan 26, 2007.
