Cost of Conversion of Flat Roof to Pitched Roof 11 January 2020 at 2:45PM edited 30 November -1 at 12:00AM in In my home (includes DIY) MoneySaving 11 replies 3K views

nad1611

Hi All. Just wanted an idea of cost for changing a flat garage/porch roof to a pitched roof. The flat roof is in a poor state with rotten wood boards under it at present. The garage will be being converted to a habitable room.

A ball park figure would be great. It's about 15m2 and we'd use red tiles to fit in with current house tiles. There won't be anything complicated about it just a straighforward swap without a window or the like.
Many Thanks

Doozergirl

About £5k or less. Ish.

theGrinch

Depends on part of the country but definitely more than £5k for a proper job.

Timbers, insulation - roof, floor and walls, roofing, plastering, waste etc etc. Thats £7k on its own plus labour so more like £14k

nad1611

Thanks. Yes more than 5k I'd say for definite. We have the added advantage of family members potentially doing the labour so that will be less than normal.


Thanks that helps.

Doozergirl

£14k for 15 square metres of roof?

There's no wonder we're busy as a company that puts pitched roofs on extensions of that size all the time if we're undercharging by that much.

Why would one need to do any plastering when replacing the roof? Roofers don't do plastering for a start, but even when people replace roofs they leave the ceilings underneath intact.

Are you asking about the roof or the entire conversion, because your headline question clearly says roof! And there's nothing in the OP to suggest it's the whole project you were asking for costs on.

traineepensioner

Doozergirl wrote: »

About £5k or less. Ish.

I'd definitely hire you.

From o/p " flat roof is in a poor state with rotten wood boards under it"
"The garage will be being converted to a habitable room"
15 m2...

Assuming simple non hip roof....

That's removing the flat roof, including covering and decking.
Supply & install timber to correct pitch.
Supply & fit Insulation to meet building control requirements.
Supply & fit roofing tiles and associated membranes & battens
Supply & fit soffits, fascia's & gutterings.
Supply & fit brickwork or Plastic stuff to fill roof gables.

I wish I could diy it for less than £5000.

ashe

People seem to be quoting for the conversion to a habitable room when the question was around conversion of flat to pitch roof, the rest of the info seemed additional information for context. Last section of the post says "There won't be anything complicated about it just a straighforward swap without a window or the like."

traineepensioner

ashe wrote: »

People seem to be quoting for the conversion to a habitable room when the question was around conversion of flat to pitch roof, the rest of the info seemed additional information for context. Last section of the post says "There won't be anything complicated about it just a straighforward swap without a window or the like."

"Hi All. Just wanted an idea of cost for changing a flat garage/porch roof to a pitched roof. The flat roof is in a poor state with rotten wood boards under it at present. The garage will be being converted to a habitable room."

Perhaps the O/P could confirm?

silvercar

You need to check the walls, could be single brick. Also, will the foundations to a garage (if any) support a pitched roof.

Doozergirl

I give up.

Say one thing and it's ridiculously expensive because x did theirs for y and posts us photos of the utter bodge that theirs is.

Say another thing and suddenly people know exactly how much it costs to DIY a roof that they openly admit to not DIYing.

Do people actually know what 15 square metres looks like? Not a lot is the answer. Some people think that they could build a house for the same price per metre as some expect to just cover a monopitch roof.

silvercar

Do people actually know what 15 square metres looks like?

I think people take garage size as the clue.

But 15 square meters would be the area covering a rectangle 3m x 5m. Or in old money about 10 foot by 16 foot, give or take a few inches.

Anyone thinking each side is going to be 15m would be covering a much larger area!