Existing flat roofs and building regs
Discussion
Has anyone had any experience of dealing with renewing an existing flat roof in the light of Part L of the 2010 building regs? We have a couple of leaks in the flat roof of our ground floor extension, which goes across the back and round the side of the house. It was last recovered in felt when the extension was extended(!)in 1996, so is probably at the end of its life. However, I downloaded a copy of the 2010 regs this afternoon, and a very quick skim through fills me with horror at the potential requirements for upgrading insulation, building control involvement and so on, should one replace over 25% of the roof area. Unfortunately the layout of windows on the first storey isn't going to allow for a conversion to a pitched roof, so we are stuck with a repair or replacement of the flat roof. Does anyone have experience of how these regs are applied in practice, please? We are just about to start getting quotes for the work, so I want to be sure that I am being given the right info by the contractors.
Thanks
Thanks
Upgrading insulation, given the current energy price rises, seems a sensible thing to do regardless of the regs.
On a personal view, if I was doing the work myself then given the age of the existing roof I'd remake the complete roof using current materials and not even consider contacting Planning/Building/whatever.
A flat roof isn't rocket science and if it leaks it's on your own head (literally
) so having a piece of paper saying it's ok is of little value, although if you're planning to sell in the near future it might cause a hurdle for someone obsessed more with paperwork than condition.
If I were getting a contractor to do it, then yes, maybe I would. And certainly if I wasn't going to be around to check the quality of the work, just to keep the builder concentrating on the job in hand.
On a personal view, if I was doing the work myself then given the age of the existing roof I'd remake the complete roof using current materials and not even consider contacting Planning/Building/whatever.
A flat roof isn't rocket science and if it leaks it's on your own head (literally
) so having a piece of paper saying it's ok is of little value, although if you're planning to sell in the near future it might cause a hurdle for someone obsessed more with paperwork than condition.If I were getting a contractor to do it, then yes, maybe I would. And certainly if I wasn't going to be around to check the quality of the work, just to keep the builder concentrating on the job in hand.
This really is one of the most ridiculous laws going, if you substantially re-tile, re-felt, re-render, re-plaster etc. you 'have' to upgrade the insulation of your wall/roof. I should imagine 90% of such work ignores building control and simply replaces like with like. I have never heard of anyone being challenged. It is utterly ridiculous that you should have to pay a fee to fix the structure/decorate your own house and have the cost of the job probably made unaffordable with the insulation 'necessity'. I would happily ignore it, whatever you do, upgrade or not.
Part L states that if you strip off more than 25% of the roof then you have to insulate it - on the proviso that the cost of doing so will give you a payback within 15 years - however if you have low window sills etc that would creat an upstand height issue then you can drop lower - a roof without any insulation will need about 130mm pur to get to current regs - cost for that is £15 - £18 per m2 then you need a vent layer and then your mineral cap sheet on top - underneath the insulation you will also need a vapour barrier ( metal lined membrane)
The down side to such an increase in height on the roof is coping with a new perimeter drip detail - they can look shocking on domestic
Its highly unlikely anyone would say anything if you didnt upgrade the insulation on a domestic property to be honest.
The down side to such an increase in height on the roof is coping with a new perimeter drip detail - they can look shocking on domestic
Its highly unlikely anyone would say anything if you didnt upgrade the insulation on a domestic property to be honest.
Not quite as simple as just stuffing in insulation, you need to look at the design warm/cold etc. and probably substantially alter the structure/rip down the ceiling to perhaps increase the depth of rafters and add correct vapour barriers/ventilation etc. You probably wouldn't get pay-back for decades. As opposed to just replacing the existing covering!
Thanks for the input, guys. It would clearly be of benefit to upgrade the insulation levels when re-doing the roof but, if it means installing a vapour barrier under the insulation as well, does that imply that the ceilings have to be dropped to achieve it, with all the implications of redecoration etc? I will have to investigate the section about payback in 15 years - sounds like a fun calculation!
I look forward to seeing how the roofing contractors approach the subject. It hasn't started very well - the first one was a recommendation from friends, but he didn't bother to turn up to arranged meetings to quote for the job (twice!). What is it with the building trade? I'm also trying to get quotes for the rebuilding of a garden wall at my mother's. It is an insurance job, but we have to supply two quotes to the insurers. Trying to get builders to provide a written quote is becoming a frustrating experience - do they not need work at the moment?
I look forward to seeing how the roofing contractors approach the subject. It hasn't started very well - the first one was a recommendation from friends, but he didn't bother to turn up to arranged meetings to quote for the job (twice!). What is it with the building trade? I'm also trying to get quotes for the rebuilding of a garden wall at my mother's. It is an insurance job, but we have to supply two quotes to the insurers. Trying to get builders to provide a written quote is becoming a frustrating experience - do they not need work at the moment?
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