While cedar is one of the most versatile and durable materials you can use to build your roof, no roofing job is complete without a proper underlayment for protection. Underlayment is placed right over the roof deck beneath everything else, including insulation.
What goes behind cedar siding?
A vapor barrier is also recommended with cedar siding. The Dupont Tyvek DrainWrap is a quality barrier with built-in channels to channel away excess water. Regardless of new or remodeling installation, Dupont Tyvek DrainWrap weather-resistant barrier is recommended before installation of the cedar siding.
What materials go under shingles?
Directly beneath the shingles is something called “underlayment,” also known as “roofing felt.” As you may have guessed, underlayment is usually either made of fiberglass paper or felt. It covers the entire roof deck.
What goes under a cedar shake roof?
Felt underlayment/tar paper: Felt materials are a traditional underlayment option for cedar shingles made from a base of natural materials like wood cellulose or synthetics like fiberglass and coated with a protective asphalt coating to repel moisture and debris.
What do you put under wood siding?
Plywood is the most common type of wood used underneath the siding. Plywood is layers of wood cut on a large machine, pressed together under pressure and glued together to form a sheet of wood. Plywood is made from maple, pine, oak, cedar and poplar. Most commonly, plywood is made of pine.
What nail do you use for cedar siding?
Hot-dipped galvanized, aluminum and stainless steel nails are all corrosion-resistant and can be used to nail Western Red Cedar. Other types of nails are not recommended. They can rust and disintegrate and react adversely with the natural preservative oils present in cedar resulting in stains and streaks.
How much do you overlap cedar shingles?
Cedar shingles should lap at least 18 cm (7 in.) over each side of valley flashing.
Does a cedar shake roof require underlayment?
Shakes should never have underlayment installed except where an ice barrier is required over solid sheathing. Instead, interlayment is required. Interlayment consists of an 18-inch-wide strip of 30-pound black felt installed between courses of shakes.
Is tar paper necessary under shingles?
Technically, no, underlayment isn’t 100% necessary underneath asphalt shingles. At least, not in areas unregulated by code! Building codes vary from one region to the next, and most all building codes require felt or synthetic roofing underlayment.
How do I choose a roof underlayment?
A majority of underlayment product offer about the same amount of protection against smoke, but flame protection may vary significantly. Look for a rating of A, B, C. An A rating is the best (this is the most fire-resistant options) and C is the worst (offers the least fire-resistance).
Do roof shingles need underlay?
Check if You Need an Underlay Membrane
If the pitch of your roof is undeath 20° they must be used to prevent the ingress of water. This is especially important if your roof has a history of issues with condensation or high humidity, in which case you should invest in a breathable membrane.
