Roof Sheathing For Slate

When replacing sections of slate or slatelike materials alternate slate courses with strips of 30 lb.

Roof sheathing for slate.

Slate roofs require about the same founda tion as shingles. Typically 1 4 or 1 6 boards of wood are installed with a 3 5 maximum space between each board directly over the roof rafters or in a cold roof system over the plywood deck. Roof sheathing may also be constructed of plywood. Also known as decking it is the wood in which the slate is attached to.

Option 5 slating lath or 1x2 to 1x4 strips of wood spaced for nailing the slate made of at least 3 4 inch thick solid wood. Different categories of wood will work except laminate woods plywood and particleboard. Goboard structural sheathing is an ultra lightweight yet durable waterproof alterna tive to heavy sheathing products. Plywood is a bit more expensive than osb but is usually stronger.

The sheathing also called decking is the wood to which the slate is attached. Felt paper isn t absolutely necessary for the roof to function. Spaced sheathing also called skipped decking refers to the construction details of the substrate which the cedar gets nailed to and thus secured to your home. Cover the sheathing no matter how green with one layer of 30 lb.

The better the foundation the better will be the roof. Century old sheathing boards can become pretty hard so if copper nails bend or deform use stainless steel roofing nails instead. Option 4 tongue in groove lumber kiln dried is suitable as a roof decking on slate roofs. Colors and shadow lines on the sample board and in the photos should only be used as a guideline and not for your final color selection.

Tarred or other waterproofed paper should be used under slate where the same is laid on sheathing boards. This will insure a roof per fectly tight against fine snow. Plywood may be used instead of osb in cases where the roof covering is especially heavy like in the case of slate clay or concrete tiles. The proper sheathing is single plank boards which can be 3 4th to 1 inch thick.

Final color selections should be made using full size shingles. Roof decking or sheathing for slate roofing must be adequate to support the loads involved but not less than nominal 1 inch lumber or 5 8 inch plywood sheathing. Slate and tile are relatively brittle expensive. Three quarter inch thick planed softwood spruce fir pine boards will last a century or more under slate.

Ideally the wood will last 150 years or long enough to support an average initial slate roof and replacement slate.