building regulations-loft conversion

flat spot · 20-12-2003, 5:04 PM

I'm going to convert my loft into a cinema room for the obvious advantages of a big screen and plenty of sound-proofed noise.

Having looked at the regulations for a loft conversion the standard price for an inspector to come and check it etc is £345

What a rip off. Just wondered how many of you lot paid for building regs on your conversion??

BestGear · 21-12-2003, 3:53 PM

Hi...

Up here in Scotland our building control regs are different in many areas...

If you are going to spend some cash converting your loft - do it properly!

It may seem an undue cost right now, but done correctly, you are adding value to your home.

One hassle is access - or rather escape... If you make the loft into a "habitable room" then you need to consider fire escape - so that means no loft ladders. A usual easy way is to convert an cupboard to fit stairs - if the wife agrees!!

If you dont want to go for the whole "official" route, then there are several books on loft conversions available... just avoid the US ones...

I would spend a fair bit of effort soundproofing the roof - 6" of polystyrene works, along with double plasterboard. The poly will also keep the heat in, and avoid condensation problems thatmany attics get. (Poly is approved by building control - it is not considered afire risk - the double plasterboard also adds to the fire protection).

I would expect the whole building warrant, plans and approvals to be completed for the money you quote - that should cover the lot start to finish.

As for DIY - no problems really... If you need to change the truss design, then take professional advice. If the trusses you have give you a clear floor, then fire away!!

Have fun

David

21-12-2003, 9:16 PM

flat spot,

Building Regs approval will be beneficial when you sell your house.

Regards

flat spot · 21-12-2003, 9:24 PM

Mmm, had considered that. Also considered just bricking it up

Gary Lightfoot · 22-12-2003, 1:38 AM

I believe you only need planning permission if any work done isn't structural, and if the room doesn't have a bed in it, then that makes a difference too. At least that's what the chap in the 'Loft Shop' told me.

Most loft conversions involve fitting steal girders to hang the new floor on and support the roof - they cut out the purlins and the supports so the roof need something strong to support the new wood that'll be holding it up. The old supports go from the roof to the central load bearing wall.

You may need to have two layers of plasterboard on the bedroom ceilings for fire protection, or some wire hangers to hold the rockwool insulation in place in case fire gets through the bedroom ceilings.

All downstairs doors have to have closures fitted with 30minute fire doors to delay fire reaching the roof. A means of escape window has to be fitted at the front of the house so the fire brigade can rescue you if need be.

When you fit insulation in the roof, you have to leave an air gap so that air can still circulate behind the insulation (between insulation and roof felt). You then fit a plastic vapour barrier before fitting the plasterboard. Two layers are better for sound insulation, but add to the roof weight.

Stairs must have a 2m headroom, and must conform to minimun tread height etc IIRC. I can't remember at what point a loft ladder isn't considered adequate.

If you want to strengthen your existing loft floor, one way to do it is to double up on the existing wooden beams - it's called 'sistering'. Your house will probably have 6 x 2s at 14inch centers, and the loft floor will only be 4 x 2s. Fitting another set of 4 x 2 alongside each and every existing one, and screwing them together will add the extra strength you need. You will need to ensure you fill it all with rockwool for fire prevention before fitting the flooring. The local regs may want the extra plasterboard or the netting if that applies.

Don't forget that any existing wiring will be affected by any insualtion it touches due to heat retention - it effectively reduces it's current carrying capacity by half, so if it's fuly enclosed in the insualtion, you may need to increase it from 1mm to 1.5mm cable (or more if it's a long run) IIRC.

There's probably lots more stuff, but that's all I can remember of the top of my head right now..

Gary.

flat spot · 22-12-2003, 11:11 AM

Mmmm, well after reading this and should you dare to look here............http://www.swansea.gov.uk/bcon/pdfs/...onversions.pdf

It seems my idea of bricking it up when I leave seems favourite

gizlaroc · 07-01-2004, 9:10 PM

I did my loft last year, the best thing to do is get an architect out and he told me what I could and couldn't do and whether it would be able to be made within regulations.
There was no charge for getting this far with him, he then asked if I wanted him to go ahead and design the loft, which would obviously be within regulations.
Originaly I had it designed with a paddle stair because there was not enough headroom for a full staircase, however the building inspector suggetsed putting a dormer on the back of the house so we could accommadate a full size stair case, this put £2k on the build, but about £15k on the value of the house, so well worth doing.
If you need any specific info just ask and I will try my best to answer, our conversion was budgeted at £12k and ended up at nearer £17k, however we had the house valued before the conversion at £189,000 and then again after at £250,000 so depending on your location and property it can be very advantagous.
We also stuck it on the mortgage and changed our deal which ended up with our monthly payment coming down.

And a screenshot for good measure