A guide to flat roof waterproofing

Keep your home warm, dry and energy efficient by reading our guide to flat roof waterproofing.

Hire a professional to install
flat roof waterproofing

Flat roofs are prone to large amounts of damp gathering across the whole of the roof on the inside, so waterproofing is essential for a long lasting, energy efficient roof.

What material is best for flat roof waterproofing?

There are currently several materials available to waterproof a flat roof against water damage and damp. Felt, EPDM and fibreglass are the most common options people choose nowadays when they are in the process of waterproofing their flat roofs.

• Felt flat roofing – for people on a budget, felt is the most plausible option when deciding to waterproof your flat roof. It can be picked up in a large quantity at a very cheap price from a lot of retailers. The main downside of using felt when waterproofing a flat roof is that felt has a short life span and will require replacement every few years or so.
• Fibreglass flat roofing – choosing fibreglass to waterproof your flat roof could be a very good choice. Thick fibreglass offers fantastic protection from possible water damage and damp. The downside to choosing fibreglass when you are flat roof waterproofing is that it can be quite expensive if you are trying to cover a large roof. Fibreglass can irritate the skin, so hire a professional to install it for you.
• EPDM – EPDM is a type of rubber, which has outstanding insulation qualities as well as being weather resistant, essential when you are flat roof waterproofing. EPDM has an expected life of around 50 years or more. This makes it perfect for people who want peace of mind regarding their flat roof. EPDM is easy to install and can be bought at competitive prices.

Will I need a professional to help me waterproof my flat roof?

Choosing whether or not to hire a professional to help you waterproof your flat roof will come down to a few variables. The size of the roof is the most important factor to consider, a larger roof will almost be too difficult for one person to waterproof by themselves so calling in a professional would be well advised. This also applies if you are moving some of the heavier materials you could choose to use to waterproof your flat roof. In some cases, it might be best to call out a professional to survey the flat roof prior to waterproofing. This will help you be alert to any potential problems you could face while trying to install.

What will it cost me to waterproof my flat roof?

Labour aside, the price of the above materials differs from place to place. Felt can be bought fairly cheap, with roofing felt costing around £9 per square metre. Fibreglass works out slightly more expensive at £11 per square metre. Finally, EPDM works out as the most expensive material you could choose, with prices around £18 per square metre.