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 is the best thickness for roof sheathing?
The recommended thickness for roof sheathing is ⅝” thick. Sheathing with a thickness of less than that is much more likely to result in bowing between framing which could potentially compromise your exterior roof material.
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.
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 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.
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.
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.
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.
Which wood is best for roofing?
Longevity. In terms of cost-savings, cedar wood is long-lasting, making it an ideal roofing material. Cedar lasts at least 10 years longer than common roofing materials, like asphalt shingles.
What type of OSB is used for roofing?
Typical types of wood used for roof sheathing are oriented strand board, known as OSB, and plywood, the most popular being OSB. Sheets of 7/16-inch thick, with no edge support, can be used in an area where the snow load is 30 pounds per square foot. With edge support and the same snow load, 3/8-inch OSB can be used.
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.
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.
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.
What plywood is best for shed roof?
CDX plywood is the most economical choice for decking your shed. For those of you that don’t know, CDX means that the plywood has a C face and a D face (A being the best). The X means that is has exterior grade glue. As long as this plywood doesn’t see any long term moisture it should work just fine.
Can you use MDF for shed roof?
A popular combination for waterproofing a shed roof is felt lining with MDF on top. This extra layer of MDF will not only keep water out, it will also help to keep the heat in. After all, heat rises and your shed roof provides an essential barrier to ensure you can actually make use of the space in comfort.