- 1 What thickness plywood is used for roofing?
- 2 What grade of plywood is used for roof sheathing?
- 3 What is better for roofing OSB or plywood?
- 4 What type of wood is used for roofing?
- 5 Which plywood is best for roofing?
- 6 Do I need plywood on my roof?
- 7 Is CDX plywood good for roofing?
- 8 Can you put 2 layers of plywood on a roof?
- 9 Can you roof over wet plywood?
- 10 Is OSB cheaper than plywood?
- 11 What is the most common decking for residential roofs?
- 12 Do I need treated timber for roof?
- 13 Why is lumber so expensive?
What thickness plywood is used 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 is better for roofing OSB or plywood?
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 is used for roofing?
Builders love plywood for its water resistance, structural stability and low cost. They also love oriented strand board, though. It costs even less and is comparable to plywood on the other two counts, and they increasingly prefer OSB for roof sheathing. Either is an acceptable choice in most jurisdictions.
Which 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).
Do I need plywood on my roof?
Aside from shingles and underlayment, plywood decking is one of the most important components in your roof. The plywood decking is integral in keeping your home free of unwanted water and mold. If the plywood has gotten wet, it can have a disastrous effect on the rest of your roof, especially the shingles.
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 2 layers of plywood on a roof?
The new plywood will have to be nailed to the rafters or roof trusses. That increase in weight should not be a problem with the single layer of asphalt shingles you will be installing, because it is normally safe to assume the roof structure is built to support the weight of two layers of asphalt shingle roofing.
Can you roof over wet plywood?
A: It is never a good idea to install a roof over wet plywood or any type of roof sheathing. Trapped water will boil when the sun heats the roof and the shingles will then have small pits where the steam finally escapes.
Is OSB cheaper than plywood?
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.
What is the most common decking for residential roofs?
Sheet decking OSB (oriented strand board) is the most common type of decking used on roofs today. It’s made up of wood chips/strips compressed together to form a flat 7/16” sheet. Plywood comes in several different thicknesses (⅜”, ½”, ⅝”, and ¾”) depending on the span of the rafters.
Do I need treated timber for roof?
5 Answers from MyBuilder Roofers Hi, no you do not have to treat for something that doesn’t exist. Breathable felt and correct installation of the roof insulation will allow the timbers to stay dry and free from future rot.
Why is lumber so expensive?
Wood products prices typically fluctuate more than most goods, because homebuilding can move up or down much faster than sawmill capacity can. Lumber and plywood prices are so high now because of the short-run dynamics of demand and supply. Wood demand shot up in the summer of pandemic.