QA

How To Install A Metal Roof Over Shingles

Can I install metal roofing directly over shingles?

In almost every case, the answer is yes, you can lay down a new metal roof over an existing shingle roof. This is one of the many reasons metal roofs keep growing in popularity – their installation doesn’t require completely tearing off the existing roof, which is a time-consuming and expensive job.

What is the best way to install a metal roof over shingles?

The first is to apply an approved underlayment over the old shingles. This is the fastest way to install but it doesn’t provide the flattest surface for metal roofing installation. The second way is to install 1×4 purlins over the shingles. This is more expensive but will also be higher quality.

Do you have to remove shingles before installing a metal roof?

Metal roofs can be installed over your existing roof without tearing off shingles, provided local building codes allow it. While shingle removal is the preferred route, tear-off is messy and raises the cost of the job.

How do you vent a metal roof over shingles?

To vent the roof, holes are cut in the old roof (Detail 1) above the soffit, which pulls air through the soffit vents underneath. Cool outside air then travels under the shingles to the vented ridge (Detail 2), pulling out moisture and heat.

Can you put metal roof over shingles without furring strips?

One option for installing a metal roof over shingles without furring strips is to use a cross-batten style. A cross-batten technique involves laying down vertical battens first. Next, the battens attach through the roof deck to your rafters. Finally, your horizontal battens are placed.

Do you need to put strapping under metal roofing?

Single wood strapping is better than no strapping, as it creates a wider gap between the existing roof decking and the metal roof, but doesn’t afford enough ventilation to resolve condensation issues. It also does not allow leveling of the roof, which corrects swells and swales on the roof.

Can I install a metal roof myself?

While most metal roofing styles can be installed as an advanced DIY project, metal roofing installation is complicated and can vary slightly based on the brand of panels or shingles that you select. We recommend that you install a metal roof with one or two helpers and fall protection equipment designed for roof work.

What type of underlayment do you use on a metal roof?

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.

Can you walk on a metal roof without damaging it?

Standing Seam Metal Roofs – can be easily walked on without damage, but they are steep and slippery. Safety equipment use is a necessity. Corrugated Steel Roofs – are also easily walked on without damage as their installation is done directly to the roof decking.

Which is better a metal roof or shingles?

Metal roofing is durable and routinely lasts 2-4 times longer than shingles. Homeowners like the idea of buying only one more roof in their life instead of potentially several. Metal roofing outperforms shingles in cases of hail and other severe weather events.

How long should it take to put on a metal roof?

Installing a metal roof can take anywhere from a couple of days to over a week depending on the weather and size of roof. If you are installing a roof on a large home or commercial building, it could take up to seven to ten days or longer. Weather also plays a role and can affect your steel roof installation timeframe.

Does a metal roof need furring strips?

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.

Do you need a ridge vent with a metal roof?

A metal roof is intrinsically durable and energy-efficient, but it needs proper ventilation to live up to its expectations. If the existing roof is properly vented, then a ridge vent is in order.

Does a standing seam metal roof need to be vented?

Energy Savings. Proper ventilation is needed to ensure the energy efficiency a metal roof provides. An effectively ventilated metal roof helps to prevent energy waste and excess cooling cost that can occur when attic heat builds up with.

Do metal roofs need purlins?

In general, purlins are used instead of traditional decking when it comes to metal roofs. Decks can help support the enormous weight of roofing more easily, and therefore are recommended for larger projects, like industrial and commercial metal roofing.

Can you put underlayment on top of shingles?

If you are dealing with a decent number of cracked or damaged shingles, you will need an underlayment installed over the shingles. This can be identified and implemented via your roofing contractor during the roofing installation process. An underlayment is meant to go over existing shingles to give added protection.

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.