Garage extension Quote- overpriced?

Had a quote for an extension to my existing garage thus;
it will be 7m long, 4.4m wide with floor to wall plate height of 2.15m only 3 walls to be built as it will come of the existing garage end. 6" conc blocks, 30sqm for the sides, 10 for the end. @ wickes prices 1.20 per block @ 10psm = 480 1 bag of cement will do 35 blocks so rounded up to 12 bags 80 tops for cement for blockwork 5 bags of sand per bag of cement @ 1.18 x 60 = 70 priced up the roof trusses already - 1500inc if i want a room in roof for storage(which i do) plain clay roof tiles, i have about 45m2 of roof area so have reckoned i need 5000 tiles..quick ebay reckoning probably about 1K for the tiles 100mm floor slab, readymix 3cubes =350 will prob go for trench fill foundations any advice on the costs/amounts of readymix?
At the start i thought i could accept a 10k bill for this, but have been quoted 20K by the builder that is already doing the extension on my house. I thought that as he was on site anyway he'd give me a good price...but looking at this breakdown i don't think he is...
Any thoughts?
steve
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do it yourself for 1/10th the price.
I take it as its not habitable, BR dont apply. If thats right, you could get 2 trees and a saw for a lot less than 1500
NT
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wrote:

do it yourself for 1/10th the price.
I take it as its not habitable, BR dont apply. __________________________________________________________________________________________________________________________
What makes you think that Building Regulations don't apply? Plus/ if these is already an extension then it is likely to need planning permission as well. The OP needs to get some proper plans done and then talk to the planners before he gets some competitive quotes.
Regards from
Peter Crosland
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On 02/03/2012 12:08, Peter Crosland wrote:

__________________________________________________________________________________________________________________________
I think we need a bit more information about if this is a detached garage, or part of the house, and also the proposed use of it once extended.
Detached garden buildings in general come under permitted development and don't usually require PP. (although there are limits if they are too close to a boundary, or use more than 50% of the curtalidge of the property etc).
PP may be required if it is a part of the house and one is proposing a change of use.
Building regs will normally apply for free standing buildings over 30m^2 floor area however - this one sounds like its borderline in that respect.
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On Fri, 2 Mar 2012 09:56:41 -0000, Mr Sandman wrote:

Not too surprising that he's expensive. Around here there are loads of house extensions, loft extensions, garages, conservatories being built. It seems like a boom time for builders, right now.
Last year when we wanted our conservatory re-roofed, people were quoting £1700 + VAT just for the polycarbonate + other materials - labour extra. In the end we bought the materials ourselves, for a smidge over £1k, and that was at retail prices including VAT.
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"root" wrote in message
On Fri, 2 Mar 2012 09:56:41 -0000, Mr Sandman wrote:

Not too surprising that he's expensive. Around here there are loads of house extensions, loft extensions, garages, conservatories being built. It seems like a boom time for builders, right now.
Last year when we wanted our conservatory re-roofed, people were quoting £1700 + VAT just for the polycarbonate + other materials - labour extra. In the end we bought the materials ourselves, for a smidge over £1k, and that was at retail prices including VAT.
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"root" wrote in message
On Fri, 2 Mar 2012 09:56:41 -0000, Mr Sandman wrote:

Not too surprising that he's expensive. Around here there are loads of house extensions, loft extensions, garages, conservatories being built. It seems like a boom time for builders, right now.
Last year when we wanted our conservatory re-roofed, people were quoting £1700 + VAT just for the polycarbonate + other materials - labour extra. In the end we bought the materials ourselves, for a smidge over £1k, and that was at retail prices including VAT.
well ive put feelers out and have two builders that are short of work coming tomorrow and Sunday to discuss. if one of them can do it for the 10k i will go with them, if not i will project manage it myself. Its been 10 years since i built my last extension so know the basics, but prices have changed somewhat! I paid each brickie 50 a day back then....
Steve
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Mr Sandman wrote:

I expect that the builder has worked it out as 30 sq m, then multiplied by 650/sq m. You don't really think that builders work out what the job will actually cost?
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