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Repair a Felt Roof

(Last Updated On: 3 June 2023)

Repair a felt roof

If a felt flat roof is leaking, there are several products available to carry out the repair to a leaking felt roof. In this post we will look at how to repair and fix a felt roof using Adiseal sealant & adhesive. We will also look at sticking roofing felt shingles with a felt roof adhesive and using the same product also as a felt roof sealant.

Reasons why flat roof is leaking

The most probable reason for a felt roof leak is due to the felt that has either developed a crack or the felt has peeled away from the surface it was stuck on. This can happen due to exposure to UV, expansion & contraction due to temperature changes or high winds. Rainwater will work its way into these gaps and will come through the roof and the ceiling below.

Flat roof leak repair

Adiseal sealant & adhesive is a great product to repair a felt roof if it’s leaking. It will provide an emergency repair to the leaking flat roof instantly as well as a provide a strong and long-lasting seal. The product is a great felt adhesive as well as a great felt roof sealant at the same time.

Best adhesive sealant to seal felt roof and to stick felt to roof.

Sealant for roof felt

The reason why Adiseal sealant & adhesive is a great product when used as a roof felt sealant is because Adiseal:

Works in dry, wet & even underwater

As Adiseal works in dry, wet & even underwater, it is possible to carry out an emergency repair on a leaking flat roof even if it’s raining outside.

Seals instantly

As Adiseal seals instantly, it is possible to check whether the flat roof leak repair has been carried out successfully. Once the repair has been carried out, pour some water on the roof to see instantly if it’s fixed.

Video of waterproof sealant sealing underwater instantly.

Provides a permanent seal

When using Adiseal to carry out a flat roof leak repair, Adiseal will also provide a permanent fix as well as an emergency repair. If done correctly, the seal will last for years.

Permanently flexible

Adiseal stays permanently flexible meaning it will not become brittle. With temperature changes, items expand & contract. Products that are not flexible become brittle and will crack or break due to expansion and contraction, causing water to leak through it. This is not a problem with Adiseal as is stays a flexible adhesive and sealant.

UV resistant

If the product is not UV resistant, there is a high chance it will fail very quickly. A roof is one of the main areas of a property where it will receive high UV radiation from the sun.

Cold applied

The traditional way to repair a leak on a flat felt roof is to use a blowtorch. This is a fire risk & not everyone will be comfortable with using a blowtorch. Adiseal can be cold applied directly from the cartridge without the need to use a blowtorch.

Solvent free

As Adiseal roof felt sealant & adhesive is solvent free, it does not shrink once applied. This is a common problem with other products. For these other products to cure, the solvent have to evaporate away, causing the product to shrink and come away from the surface it has been applied to. Cheaper products tend to have more solvents leaving a weaker bond than Adiseal.

Another problem with solvent based adhesive & sealants is that the solvents will attack sensitive materials like polystyrene which is a common insulation material in building roofs, walls & other places.

Strongest Adhesive

As well as Adiseal being a great sealant, it also proved to be the strongest adhesive in an independent adhesive strength test by Ultimate Handyman. In the test Adiseal was over 3 times stronger than the nearest competitor. Further details of the test are on the Adiseal page.

How to repair a flat roof leak

How to repair a flat roof leak

  1. Find out where leak is.

    To fix a felt flat roof leak, first find out where the water is working it’s way through the felt roof. This will usually be a crack in the felt or where the felt has peeled away from the roof surface. Pour some water on the felt roof to see how the water runs into the gaps.

  2. Clean area.

    Once the location of the leak has been found, thoroughly clean the area. Brush away any loose debris. Use Adisolve solvent cleaner to remove any oil, grease, bitumen & other stubborn deposits. Use a fine brush like a painting brush to clear any fine dust.

  3. Apply roof felt sealant or adhesive.

    Once the area has been cleaned thoroughly, apply the Adiseal sealant & adhesive into the crack or gap.
    Tip: If using Adiseal to seal a crack in the felt, start by applying Adiseal at the point where the crack is nearest to you and move away to the other end on the crack. This will push Adiseal into the crack creating a much better seal.

  4. Remove excess.

    Apply extra Adiseal on top & use a smooth flat surface to flatten the sealant. To remove any excess Adiseal, use a thick cloth. Adisolve solvent cleaner can also be used to help remove any excess Adiseal.

  5. Test seal.

    As Adiseal seals straight away, it is possible to test if the felt flat roof leak has been repaired immediately by pouring water around that area. Adiseal sealant & adhesive will take 24 to 48 hours to fully cure but the seal is instant.

Repair a felt roof when wet. Adiseal adhesive and sealant will seal a leak instantly and stick felt even in the rain.
Image of felt adhesive that has failed. Repair can be done in wet with Adiseal.

Adiseal is a muti-purpose product that will also fix a leaking gutter.

Adhesive for felt roof

Adiseal is also a great adhesive for roofing felt as well a being a great sealant for felt roofs.

Adhesive for flat roof felt to stick felt to roof that needs replacing.
Image of roof felt shingle adhesive that needs replacing.

Adiseal adhesive & sealant is ideal when used as an adhesive for roof felt shingles, felt lap as well as sticking larger felt sheets. One advantage of Adiseal over other adhesives is Adiseal will also provide a strong waterproof seal as well as sticking the roofing felt.

How to stick roof felt shingles & felt lap

To stick roof felt shingles make sure the surface where the felt roof adhesive will be applied is thoroughly cleaned. Use a brush to remove any loose debris. Adisolve solvent cleaner is the ideal product to clean & remove oil, grease, tar, bitumen & many other stubborn deposits. Use a fine brush like a painting brush to remove fine dust from the area where the adhesive needs to be applied.

Adiseal can be cold applied. Simply apply Adiseal adhesive & sealant to one surface & press down the roof felt shingle. Adiseal can take 24 to 48 hours to fully cure but seals instantly.

Where to buy

In the UK, Adiseal products can be purchased from Adiseal stockists. For other countries visit www.guglue.com

Frequently asked questions

How quickly will Adiseal stop a leak on a felt roof?

If applied correctly, Adiseal will repair the leak instantly on a leaking felt roof. It can take Adiseal 24 to 48 hours to fully cure but the seal is immediate.

Can Adiseal stick a felt sheet that has peeled off from the roof?

Yes, Adiseal will stick a felt sheet that has peeled off. It will provide a very strong long lasting bond and will also seal at the same time.

Can felt roof adhesive stick to other materials?

Adiseal adhesive & sealant will provide a strong bond to many different materials. It’s not limited to just felt roof adhesive applications. In most applications, it will outperform dedicated products.

Can roof felt be stuck on when the surface is wet?

With Adiseal adhesive and sealant, the felt can be stuck on in dry and wet conditions.

Will roof felt sealant stop a leak in an instant?

To carry out a emergency repair, Adiseal adhesive and sealant is suitable for both emergency repair and a permanent fix.

What is a good roof sealant?

Adiseal is a great roof sealant. It can be used to fix and repair many different items on a roof including felt & lead. It is a waterproof sealant and adhesive that is very strong, UV resistant and stays flexible.

How to use roof felt adhesive?

When using Adiseal, it can simply be cold applied directly to the roofing felt. To get the strongest bond, Make sure both surfaces are clean where the adhesive will be applied. Simply apply Adiseal to 1 surface and push down the roof felt. Temporary supports might be required until the roof felt adhesive fully dries.

Suhail Matadar has extensive experience in the construction industry as an electrician, involved in installing, inspecting, and testing electrical systems in various projects. He excelled in sales, working for a major UK wholesaler, selling construction products to professionals and the DIY market. Suhail's background includes working at a leading home emergency repair company dealing with trades people. With a BEng (Hons) degree in Electronic Engineering, Suhail has worked with PLCs in the nuclear fuel manufacturing industry. During his studies, he gained practical experience at a chemical manufacturing company known for producing award-winning cleaning, hygiene, and livestock protection products for over a century. Currently, Suhail runs a global business specialising in supplying, researching, testing, and distributing chemical construction products like adhesives and sealants.

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