QA

Quick Answer: What Goes Under A Metal Roof

What do you put down under metal roofing?

The traditional and most common material used for roof underlayment on a steep-slope metal roof is non-perforated, asphalt-impregnated felt underlayment. There are several types of felt underlayment including both organic reinforced and inorganic reinforced.

Do I need underlayment for metal roof?

The short answer is yes, your metal roof does need underlayment . But like most things in life, it’s not quite that simple. While most building codes require underlayment, there are some instances where underlayment may not be considered necessary.

Can you put metal roofing directly on plywood?

Metal roofing should not be installed directly over the top of bare plywood. You do not have to install roofing shingles or other roofing material, but a felt sheet over the plywood is the bare minimum. When the metal expands or contracts with changing temperatures, it can tear or wear away the felt sheeting.

What are the boards under a metal roof called?

Underlayment is the layer of material underneath the panels. It provides a layer of protection against moisture, ice, extreme temperatures, and more. Underlayment is required by code beneath all metal roofs, even if you choose to leave old shingles or other materials in place when re-roofing.

Do you need OSB under metal roof?

The simple answer is yes, your roof does need an underlayment. Traditionally built homes will need an underlayment. If your home is built with joists, insulation between those joists, and sheathing, then an underlayment is needed before you put on a metal roof.

What roofing underlayment is best?

Synthetic Underlayment This is currently the most popular choice for roof underlayment, and with good reason. Made with an asphalt-saturated basemat and fortified with a mix of fiberglass, this product is not only extremely water-resistant, much stronger and more resistant to tears than other types of underlayment.

Do I need furring strips under metal roof?

When installing a metal roof over an existing roof, insulate the spaces between the wood strips with rigid insulation to prevent condensation before installing the roofing. You also need to add furring strips. Twenty-four inches is a common spacing of furring strips for a metal roof.

Can metal roofing be screwed to OSB?

No, you do not need to screw into solid lumber (joists, stripping,etc.). As you can see, the thinnest material they recommend is 1/2” (7/16”) OSB board at 9” on center up to 24” on center. Be sure to follow their instructions in order to obtain the warranty.

Does a metal roof need a vapor barrier?

Metal roofs and buildings require specific insulation and vapor barrier to meet the demands of condensation and breath-ability. Depending on whether your building is sheeted or not, or if you require insulation, we have it all, including the necessary tapes for installation.

Does metal roof need moisture barrier?

To avoid condensation buildup with your metal roof, you will need to have a moisture barrier in place. When the air in the home is warmer than the air outside, condensation will collect. If the roof system is not ventilated properly, condensation can also collect.

Can you put metal roofing directly on rafters?

Metal roofing can be installed directly on open rafters. The vapor barrier built into such insulation helps to minimize the amount of condensation that drips down from the roof, and the insulation itself can help to keep the interior of the building at a comfortable temperature.

Can you walk on metal roof?

Metal roofing can be walked but, homeowners should refrain from doing so for safety reasons. If a contractor does need to walk your roof, they should practice sound safety procedures and follow OSHA safety requirements.

Should a metal roof be installed over battens?

By design, some metal roofs MUST be installed over battens, some MUST NEVER be installed over battens, and some can be installed over battens OR solid decking. So, whichever way you go, it’s important to choose the right product and install it per manufacturer specifications.

Does a metal roof act as a radiant barrier?

As you walk up to a jobsite and see metal roofing installed, you may wonder, “Is a radiant barrier necessary with a metal roof?” The answer is yes. Metal roofs reflect the sun’s UV and infrared light rays that contribute to roof surface radiant heat rather than absorb it, which can reduce cooling costs.

Can metal roofing be installed without sheathing?

Although it may seem counterintuitive, metal roofing can be attached directly to your building’s roofing structure without the need and expense of plywood sheeting.

What is the best metal roof underlayment?

Known by many different names (including felt paper, roofing tar paper, and asphalt-soaked felt), felt underlayment is the most commonly used type of underlayment material on steep-slope metal roofs. Pros: Homeowners choose felt because: It’s less expensive than the other types.

Do you use tar paper under metal roofing?

Historically, asphalt-saturated felt underlayments, sometimes called roofing tar paper, were the go-to roof underlayment choice. To offset this disadvantages, we recommend selecting a synthetic underlayment for metal roofing projects instead of the asphalt family of products.

What are the different types of roofing underlayment?

There are three basic types of underlayment used beneath roofing materials: asphalt-saturated felt; rubberized asphalt; and. non-bitumen synthetic.

Is peel and stick underlayment worth it?

In areas prone to strong wind and rain, peel and stick underlayment is always a better choice compared to traditional solutions like asphalt. Peel and stick is significantly more efficient in minimizing the risk of water infiltration and damage.

Which is better felt or synthetic underlayment?

With that in mind, synthetic underlayment is more durable than felt underlayment. Felt underlayment is much more prone to rip from high winds and during the installation process. Synthetic underlayment also holds nails better and repels water instead of absorbing it.