Is it OK to roof over an existing roof?

Installing a new roof over an existing one can only be done if you have shingles because you can only put shingles over shingles. It is not possible to mix materials, nor to install a new layer over slate or wood tiles.

Can I build a roof over my roof?

The answer is Yes. You can put new shingles over existing shingles that are in good condition. However, you can only install new shingles over asphalt shingles that meet the re-roof conditions. Also, you cannot mix materials; for instance, you cannot install shingles over wood tiles or slate.

Is it okay to overlay a roof?

Yes. And in fact, that's the primary reason a homeowner opts for an overlay roof. Since an overlay roof is just put on top of the existing roof, your roofer's crew doesn't have to tear off your existing shingles, redeck the roof, or do as much cleanup.

Is it OK to reroof over old shingles?

While a repair job can often be more convenient and somewhat more cost-efficient, placing new shingles over old ones is never a good idea. Whether repairing one section of roof, or a replacing a whole one, it's always best to pull up the old shingles before putting down the new ones.

Can you put a second layer of roofing?

Adding a second layer of shingles will make your roof hotter because heat gets trapped between the shingle layers. Increased temperatures can lead to premature aging of the shingles. Layering new shingles on top of old ones, which might be curved or damaged, can result in some visible imperfections on your roof.

Can I Install New Shingles Over an Existing Roof? [Northern Virginia Roofing Tips]

What is one of the drawbacks to adding a second layer of roofing over a first?

Adding a second layer could compromise the structure of your roof. Problems fixing leaks: A second layer of shingles only complicates the job when a roofer is trying to fix a leak. Often, there is a problem with the first layer of shingles that was not apparent before the second layer was added.

How many layers are allowed on a roof?

House roofs should never exceed three layers of shingles. Adding additional layers without excavation can save homeowners up to $1,000 in labor. Therefore, layering has advantages. Building and city codes require roofers to limit shingle layers to two.

Is it OK to put two layers of shingles on a roof?

In most states, you're only allowed to have 2 layers of shingles on a roof for fire safety reasons. However, you'll still see roofs that have 3 or 4 layers today. If you already have 2 or more layers, a contractor will recommend a full replacement.

Can I put 3 layers of shingles on my roof?

No, you can't put three layers of asphalt shingles on a roof. In most states, you're only allowed to have two layers of asphalt shingles on a roof for fire safety reasons. But that doesn't mean you won't still see roofs with three or four layers today.

How long does a roof overlay last?

An overlay is a viable option if the existing roofing materials have not already been overlaid. Home Reference.net notes that on average you can expect the overlay to last for fifteen or sixteen years.

Is it better to remove old roof?

The main advantage of leaving the old roof on is obvious—you can minimize the mess, removal costs, and disposal expense if you can leave the old shingles in place. Other advantages are that you end up with an extra barrier against leakage and a little extra insulation.

Is a roof overlay considered a new roof?

Tear-off roofs are when a roofing contractor removes, or “tears off,” your existing roof, then installs an entirely new one. Overlay roofs are when a roofing contractor keeps your existing roof as-is, then places new roofing materials on top of it.

Do I need planning permission to change the pitch of my roof?

Unfortunately, the answer is YES, YOU NEED PLANNING PERMISSION TO CONVERT A FLAT ROOF INTO A PITCHED ROOF. Any time you make changes to a property that makes it higher than the previous highest point, you will need planning permission to carry out the work.

How long does a third roof layer last?

Vented properly and installed correctly, you should get around 80-85% of the life span out of an asphalt roof. That means you can expect to get about 20-22 years out of your 3-tab shingle roof and 25-28 years out of your dimensional shingles.

Can you put plywood over old shingles?

As long as the new plywood itself can span the distance and carry the roof, wind, seismic and snow loads for your region, adding new ply over old is just fine. The new plywood thickness should be at least equal to the exusting plywood thickness.

How long is a roof good for?

Slate, copper and tile roofs, which are on the upper end of the price spectrum, can last more than 50 years. Homeowners with wood shake roofs should expect them to last about 30 years, while fiber cement shingles last about 25 years and asphalt shingle/composition roofs last about 20 years, the NAHB found.

How much does it cost to add a layer of shingles?

On average, you can expect to pay a contractor $3 to $6 per square foot to install your roofing. Prices can be higher if you choose a unique or complex shingle. The contractor will have to dispose of shingles, which costs an extra $25 to $150.

Can you put a metal roof 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.

How do you add a second layer of shingles?

Remove shingles from any area where you notice deterioration or damage to the roof decking. Replace the damaged roof deck with 3/4-inch OSB board. Add a layer of shingles over the newly repaired area before you install your second layer of shingles.

What is one of the drawbacks to adding a second layer of roofing over a first quizlet?

ROOFING - Drawback (inconvenientes) to adding a second layer of roofing over a first: The dead load is increased; Nails may not be long enough to penetrate the roof sheathing; Old flashing may not be replaced; the roof sheathing cannot be properly inspected; Roofing materials may not dry properly.

What is a double roof?

Double Roof is defined as a roof framing system in which the rafters rest on purlins which provide intermediate support. In double roof, each rafter is supported at three points: At the bottom; on the wall through wall plate. At the top; by the ridge. At the centre by a purlin.

Can you put a second layer of shingles over architectural shingles?

The quick answer is yes you can re-roof architectural shingles over existing architectural shingles (however you must check with the shingle manufacturer as well). Having said that it will be nearly impossible to get a good looking quality installation.