geoffxr4

I am currently doing a loft conversion and have read up on all the regulations etc. I was just wondering if anybody has experience of building control and how strict they are?For example everything has a target thermal insulation but how strict are they at imposing it?

My headroom in the loft room will be 6'11" ish but if i stuck to the regulations exactly then it wld have to reduce to 6'9" to get all the insulation and full ventilation gaps in. My dad has done plenty of extensions in the past and never bothered with all the insulation and always been signed off. However the last one he did was about 4 years ago and things may have changed since then.

Cheers

dojj

iTrader: (3)

they've changed a lot in the last few years

my neighbough did one last year and he had to fit a kiddie gate to the stairs for some reason ebfore they would pass it

the benno

best to check with your local building control mate, they can be funny buggers if it aint done right

bad boy rs

iTrader: (7)

The insulation will have to be checked by building control, so unless you want to

insulate it then take it out is it worth it

Lee Reynolds

Minimum of 150mm kingspan/xtratherm or similar in the roof space preferably with a 50mm gap above between insulation and roof felt. 100mm Kingspan/xtratherm or similar in the eaves walls/dormer cheeks.

and yes they are strict.

shane

Im a joiner mate and as Lee mentioned above they can be very strict, especially when it comes to safety(ie; stair gate mentioned above) and insulation.

Lee Reynolds

Also forgot to mention if its going to make it 3 storey Ie a two storey house currently then a loft conversion you may have to double board the ceilings for fire protection.....for some reason though we find this is not always the case....another reson to always contact building control as ya never know!

D7AKE

Wrong lol...minimum 130mm depending on the "R" Value of the material you are using...

me I would Concider a multi foil insulation 10mm thick, will be more expensive but its easier to use.


Hope this helps

Si

D7AKE

Lee you dont have to double board,I think some LA talk shit when it comes to the Regs, you will however need 15mm PB on First and Ground Floor Ceilings (in domestic situations)

unless your going by the Scottish regs and then I will retract my statement...

Si

PS I am Divisional Building Control Suveyor for my my LA.

D7AKE

If you want to Know anything bout Building Regs, happy for you to phone me any time I have PM my number, I also have a full 50 page document on Loft Conversions I can send you for free or you can download it, tbh I always have a flexable approach when it comes to the Regs but it really depends on your Build Inspector!

Si

polly_x

iTrader: (2)

Ive just finished a big conversion on our house so been through this. As D7AKE says your best to take advice as you go along. We used a mixture of the Kingspan foam board and thinsulex foil sheet to achieve the correct insulation rating and save on space. I may be wrong (D7AKE can confirm) but each council can still have different products on their approved list so make sure you check that too. I know of the 3 leading foil insulation products, my area (east Herts) only had one on their approved list.

I ensured that as we were building, we had the inpsector round to see how it was being put together at each stage. That way he had no pulling stuff apart to prove at the end and made it all plane sailing. It also meant he gave guidance on the way which helped.

Not sure about the ceilings. We never had that issue. But you will need to consider fire escape as the rules changed last year. We ended up having to fit fire doors with 1 inch stops on every habitable room in the house to pass the building regs in the end. At £50 a door, plus the fitting, new stops and painting it can easily add a grand to your price to put 5 or 6 new doors on.

In summary, my advice would be to get building control to sign off your design before you start and then keep them involved. That way you should not get tripped up aling the way.

D7AKE

Top Advice Polly!

geoffxr4

Thanks for the advice. I've planned it to specification and at the moment its:

1. 150mm ceiling joists with Celotex 120mm between the joists and 25mm beneath plus my plasterboard etc. However, this means the ventilation gap at the front will be 30mm instead of the regulation 50mm (increasing backwards as the firrings rise) U-value 0.2 W/m2k

2.Sticking totally to the regs it's 100mm celotex with 35mm below u-value 0.2W/m2k which gives me a clear minimum gap of 50mm above the insulation

Somebody over on ebuild pointed out that loft insulation must meet minumum energy efficiency values as set out in the approved document with the proviso that it is techincally or functionally feasible. If not then best standard which can be achieved within a simple payback of no greater than 15 years.

http://www.planningportal.gov.uk/eng...315785835.html

I'd like to keep headroom to a minimum of 6'10" really as anything below this seems a bit low so maybe i'll get away with it. I think i'll check out this thinsulate stuff and then sent off to BC and see if i can negotiate on the headroom.

geoffxr4

That's a very generous offer, thank you.
I wont take up your time but if you could point me in the direction of where to download the loft conversion document that would be very helpfull

The brilliant thing about passionford is that there is always somebody who knows the answer to a question

geoffxr4

Another quick question for those in the know

just been calculating my own U-values and celotex XR3120 has an R-value of 5.2 m2k/w.

U-value = 1 / r = 1 / 5.2 = 0.19

i think i must be missing something as this suggests that 120mm of this is sufficient?

Thanks

PAUL S

iTrader: (8)

I found a great company on ebay for all forms of Kingspan - sold as seconds but all the batches I have had so far were spot on with no damage at all.

much cheaper than the merchants and they have regular auctions

http://myworld.ebay.co.uk/secondsandco/

or you can buy direct

www.secondsandco.co.uk

interpretation of the regs vary from council to council and even between inspectors - in my area the thin foils are not approved at all, but they accept 100mm of kingspan between the trusses

edited to say on new builds you have to double board the ceilings between the first and second floors and fit fire doors on all the upstairs exits, but on refurbs/conversions you only have to fit pirco door closers to the existing doors upstairs and no double boarding is required, and have a means of escape window in the roofspace.

Lee Reynolds

Si while i respect your a building inspector this is what i mean about checking because it always different in certain areas. You are suggesting using 10mm multi foil....by this i assume you mean superquilt? As that is NOT PERMISSABLE in the wakefield area! You can only use that stuff IF you underdraw it then with 50mm kingspan. And the min of 150mm kingspan i refered to i just read off the current drawings i have on the desk...

Now on the 15mm FB to the ceilings....im talking of overboarding the existing ceilings not ripping down to install fireboard....

Like i say, its different areas....

Lee Reynolds

exactly. I heard from a good source that Kingspan and Xtratherm ETC got together and tested the superquilt etc loads as they were in fear of the market being cornered and them losing mass trade. they did it and it doesnt give the supposed equivilent to 300mm rockwool as it states!

We found this out after buying the twatting stuff