For rafters spaced 20 or more inches apart, 1/2- or 5/8-inch plywood is recommended. The most common rafter spacing is 24 inches, and 5/8-inch plywood is recommended for that. … Roofs with very heavy loads may require 3/4-inch thickness.
Can I use 1/2 inch plywood for shed roof?
If the shed is for light tools then 1/2 inch pressure treated plywood is acceptable. If the shed is for heavier storage, then pressure treated 3/4 inch exterior-grade CDX plywood is the best.
What is the minimum thickness of roof sheathing?
Roof Sheathing Code Requirements
The minimum requirement for roof sheathing is ⅜” thick. There is no upper limit on how thick your roof substrate is. Thickness allowed depends on how far apart rafters or trusses are spaced and the rating of your roof decking.
What size plywood is used on a roof?
Plywood Thickness for Roofing
The thickness of the plywood for the roof should be a minimum of 1/2 inch, but 3/8 inch is standard size. Most roofs will be sheathed in plywood at least 3/8 inch thick. Bigger is better.
Can you use plywood for roofing?
You can use any cheap plywood or even particle board as a short term sheathing on a shed roof, but cover it with a layer of rolled roofing. As Sharptooth said, it will delaminate in no time if not covered. Roll Roofing is inexpensive and easy to install.
What thickness plywood should I use for shed roof?
Roof and Floor
If you want the shed to be waterproof, its roof must be constructed just like any other roof — a plywood decking covered with shingles or with composite or metal roofing. Most builders use 15/32 CDX for the roof; it is an exterior-grade plywood with a thickness just under 1/2 inch.
Should I use OSB or plywood for roof?
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 size nails should I use for roof sheathing?
Step 3: Fasten Roof Sheathing Panels Properly. Fasten panels with a minimum of 8d Common (0.131-inch by 2-1/2-inch) nails spaced a maximum of 6 inches on center at supported panel ends and edges. At intermediate supports, fasten panels 12 inches on center. In high-wind areas, more fasteners may be required.
What is standard roof sheathing thickness?
The typical thickness of roof sheathing is about 7/16-inch, which is just under 1/2-inch.
What thickness OSB for a roof?
The thickness of OSB that you need varies on where it is used in a building. Typically 3/4″(18mm) for floors and 3/8″ (9mm) for walls and 1/2″ (11mm) roof. Also make sure that you get your supporting timbers at the correct spacing.
What’s the best plywood for roofs?
Plywood gets it strength from multiple layers of wood bonded together. The wood grain alternates from layer to layer, adding significantly to the strength of the plywood sheet. A special grade of plywood called “CDX” is a popular choice for roof sheathing.
How much does a sheet of roofing plywood cost?
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.
Which plywood is good 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 CDX plywood good 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.
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.