Extension roof: Flat with roof lantern or pitched with sky lights - velux ?

[evie2468]

Advice please. We are adding a small extension 2.5m depth by 10m wide. We will put in glass doors across the back.

BUT can't decide on a flat or pitched roof. I believe there are now few issues with modern flat roofs. My main concern is the light and heat. The room is south facing and benefits from the lovely warmth of the sun.

My concern is it getting too hot from a roof lantern. Also the TV will be at the garden end of this room on the wall below the lantern. Will this be a problem with reflection. At the moment we just close our curtains. Thanks

Stay clear of flat roofs. We had some put in and they’re nothing but trouble. Standing rain water leading to leaks. Go for Pitched roof every time!

Thank you. Was that recently?

Our roof lantern gathers insects and we can’t watch the tv beneath it. Go for opening velux windows

Hi, we had a flat roof with roof lantern put in in 2021. No problems with it so far. It’s our kitchen extension-the roof starts under DD’s bedroom window and she can climb out and sit on it to read which she loves!! Ours is north facing. Not had any problems with heat. It can get noisy on the lantern when there’s heavy rain.

If you go for a pitched roof with Velux, I think the minimum pitch has to be 15 degrees for their standard skylights. Double check that what you have designed will work - not like our architect. As a result we had to have big boxes raised above the pitch to get the Velux to the right angle.

Pitch
Our flat roof leaked after 3 years.

Also, some home insurers charge more for flat roofed. See also, tall trees close to the house.

There shouldn't be standing water on a flat roof. It will have a slight pitch to it, otherwise it hasn't been installed correctly.

Insurance only gets more expensive if over a certain percentage is flat roofed.

I'd never get a flat roof. They should be angled but I'd always worry that the builders won't do it. See upthread for people who had flat rooves installed recently that clearly aren't pitched correctly.

We have pitched. Don’t forget soundproofing. Echo is a bitch

We have a flat roof. It is covered in GRP and has a slight pitch for water runoff. Had zero issues.

I agree opening skylights are a major plus, for letting out flies and for ventilation. We have flat roof skylights which open electronically.

It’s really down to what look you prefer IMO. Both can be built in a reliable way with proper use of materials.

Why put the TV at the garden end, if you’re worried about glare then put it at the dark end?

20sqm isn’t that small!

We have a large lantern on flat roof, it will fill with bugs in warmer weather but it looks beautiful and really makes the space feel less oppressive. But If I had an option to have an opening on it I absolutely would.

I also agree with flat roof

however @okthenwhat interesting use of rooves, I am sure I was taught this at school but rarely see it and it comes up on predictive text as being a wrong word. Wonder if this was a typo or you also got taught it at school!

@CorBlimeyGovnr I genuinely don't know! I think I was taught it? You've got me doubting myself now. Up is down. Left is right. Black is white. Where am I?

I have a lantern with a flat roof. There's no problem with the roof and the lantern gives lots of light but it is very hot in the summer.

Yes a major benefit of Veluxes is you can now get built in sunshades for them. Our skylight definitely lets in a lot of heat (also S facing)

I imagine it’s maybe down to workmanship, maybe materials used in recent years. We have a flat roof which is at least 30 years old and no problems to date, fingers crossed!

I have the opposite problem to others, my lantern is great and have had no problems at all with the modern flat roof and it creates a beautiful bright space, but a Velux elsewhere in the house has caused damp issues that we are struggling to resolve

Absolutely agree with everyone else - pitched with velux!!

Definitely pitched with velux. We had an extension at the same time as our next door neighbour - ours is pitched an hers flat. She has had various issues and we’ve had none.

I would avoid a flat roof at all costs!

We had our kitchen extended just over a year ago and went with pitched roof and velux (2 either side) and we couldn't be happier with our decision.

We have a flat roof for our extension with a velux. Slanted for drainage in keeping with our existing extension. No problems. Love it.

The appearance of a pitched roof from the outside is significantly more appealing IMHO.