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Cost of an extension?
richard thomas - 9/11/08 at 01:20 PM

Been trawling the net for info, but as usual end up back here where the experts are....

Looking to buy a house and build an extension on top of and rear of the existing double garage on the side - tying it in to the house, in order to give another bedroom upstairs, and larger kitchen downstairs behind garage.

Anyone got an idea what rough cost it might be? Just for the structural building element i.e. footings, walls and roof, can fit it out myself I reckon....

Rich.

mookaloid - 9/11/08 at 01:22 PM

very rough guide, £1000 per sq metre

richard thomas - 9/11/08 at 01:23 PM

Would that be per storey?

richard thomas - 9/11/08 at 01:47 PM

Ta Chris,

To be honest it's been done on the original garage to a couple of the houses round here previously, but I don't know anyone well enough yet to ask what they paid...plus I'm guessing that they will have paid a builder to do the lot from start to finish - I'd like to save some cash by fixing out myself, reckon that's going to be a biggish saving.....

rgr33n - 9/11/08 at 02:30 PM

quote:
Originally posted by richard thomas
Ta Chris,

To be honest it's been done on the original garage to a couple of the houses round here previously, but I don't know anyone well enough yet to ask what they paid...plus I'm guessing that they will have paid a builder to do the lot from start to finish - I'd like to save some cash by fixing out myself, reckon that's going to be a biggish saving.....


mookaloid's rough guide will give you a fitted out and complete extension. i usually work in sq ft, and would have assumed a figure (probably a maximum) of £100/sq ft. that's per sq ft of accomodation, so it there are two floors of extension, measure each and then add the total floor area, then multiply that by £100.

i added a bedroom, bathroom, garage, kitchen and conservatory to my house (a 30's style semi) and the shell cost me £30k. some of my neighbours have had similar but smaller extensions completed for around that sort of money but i wanted to handle my own finishes (plus i have installed a cat5e network in my house and didn't want my own work to be an excuse for my builder to claim an extension of time).

as others have said, it may be likely that your garage foundations are suitable to support an additional storey. if not you will have two choices - punch through the existing sub floor to build new pads off which to support the additional storey or demolish the garage and start again. if the garage was built fairly recently (ie probably within 10yrs) you may find that the foundations are suitable to support the additional floor a;ready. if the garage is recent, then your local council's building regs dept will have details of the fdns on file

if it;s anything like mine, the extension could cost you between £20-30,000 depending on the level of finish you expect to the shell (ie windows, doors, services, first/second fix plumbing, first/second fix electrics etc etc)

hope that helps

richard thomas - 9/11/08 at 03:08 PM

Nice one!!

To be honest, 30K was the figure I had in my head for some reason....hoping that the garage footings are good enough - that said if not it's just a case of demolishing it and starting again I guess.

I'm guessing that there are a few brickies out there lo0king for work at the moment....I'm hoping that project managing it myself and just contracting out for labour etc. will save a bit?

scootz - 9/11/08 at 04:59 PM

Think of a (big) number... treble it and multiply by 10... and that's just the time it will take to build the bloody thing!

Seriously though... as said before about £1k per SQ M is what I'm finding for my own project. I always thought this figure pertained to a new build, but seems to also relate to a refurbishment

grazzledazzle - 9/11/08 at 06:09 PM

/shameless plug /
I'm an architect, give me a yell if you need some help with drawings and planning. Locost rates available!

richard thomas - 9/11/08 at 06:14 PM

Thanks, will bear in mind when I get to that point.

owelly - 9/11/08 at 07:03 PM

I've found, and so have my builder mates, that they are now working for the same hourly rates as they were ten years ago!!
I found this out whilst finding quotes to rebuild my garage into a house and the quotes I'm getting now are 20% cheaper than they were last year for the same work!!
The good builders are still busy but the prices are reflecting the current market. If you get a quote, make sure it states exactly what is included and have a timescale for completion so if the market picks up, they can't suddenly put the price up or go off on another, better paid job!!

richard thomas - 9/11/08 at 07:15 PM

What's the general going rate for a brickie these days?

JoelP - 9/11/08 at 07:52 PM

30p per brick or £1 per block, minimum.

richard thomas - 9/11/08 at 07:58 PM

Might take it up myself....

Peteff - 9/11/08 at 10:42 PM

quote:
Originally posted by richard thomas
Might take it up myself....


That's good, you'll be able to set yourself on and pay your own wages. It's the wrong time of year to be doing the outside work though