Flat Roof Advice for Newbie - Surrey

[goncalossantos]

Hey all,

We bought a property with an old 30sqm bitumen felt octogonal flat roof above the main bedrooms. It has been described as watertight but with ponding. We are also suffering a lot with overheating in the summer from heat transfer from the roof, and I imagine that the insulation under the felt is also not great and that there is also heat loss during the winter given how old the roof is but I haven't had a thermal survey done yet.

I am completely lost as this is the first time I have dealt with roofing. I have done some research, but want to ask the experts:

• What would be some suggestions on hot to improve the reflectivity/insulate? Can I get by by simply coating the existing roof in some reflective paint? Or should I consider a full replacement? The first roofer that came over ofc said that it was urgent to replace but that is expected.
• If replacing, I have been told that fleece backed epdm would be a great option. A lot of people in the UK try to do GPR but I don't want that from what I read is finicky and loud when raining. I understand that EPDM would not easily paintable and that it is not great a solar reflectivity, what would you do in my case to have a long lasting roof that also has good thermal insulation? Would EPDM + PIR layer between the joists be acceptable?

I'm starting to get companies to come in and give quotes. Any other things I should be asking the roofers?

 

[Deluks]

Lots of ways to redo a roof.
If a cold roof you need vcl and venting.
If warm then you'll likely lose height, and need to deal with the side effects of that.

You will most certainly have to upgrade the insulation to modern standards, this is controlled work.
Guarantees are worthless if the builder shuts up shop and does a runner, ask around on your social media if anyone has had a flat roof done in the past and if they'd recommend someone.

Get it in writing what they intend to do, the more detail the better. Then that will give you a clue if they know what they're doing.

An inverted roof might be suitable option for your situation.
EPDM is suitable, but pir between the joists would also need vapour control underneath, which could mean disruption to the ceiling below.