Extensions Question

Getting quotes for single storey side extension

Have just obtained Planning Permission for single storey side extension and have detailed drawings from architect. Now need to approach reliable builder for quotation. Are the drawings enough for him to work from? Do I need to supply any detailed specification of my own? If he can work from the drawings, can I expect/request a detailed specification from him? Reading other questions, £1250 is quoted as a reasonable price per sq m. I live in Herts - would this be a reasonable estimate for this area? (House is 1930s semi.)

In addition to the extension, I am hoping to replace double glazing, flooring and generally revamp the whole house. Am not sure what I'll be able to afford so need pricing to be of a "pick and mix" variety where I can choose to do some jobs but not others if money is too tight.

Don't want to ask these questions directly to builder in case they think I am naive and take advantage of the situation.

Advice most welcome. Thanks in advance.

2 Answers

Best Answer

Hi Anjo56, The answer to your question would be that £1250-£1500 is a good guide of thumb to start with, but the ground conditions relating to the site are a big determining factor and could play a big part in the final cost, even the best builder can not guarantee what they will find once groundworks start, so please be realistic in your contingency.
Again, as Roc builders say, your builder HAS to visit the site before any quote/estimate can be given, I personally will not give a fixed price quote on any extension job, as there are too many factors that will affect the cost of the job, that cannot be factored in with initial visits, as a fixed price would price me out of the market to cover all possibilities.

As for the windows etc, are you aware that if you put in the building notice for the extension you can include the replacement windows in the spec reducing the overall cost of having to have a Fensa or similar registered fitter do the job, and any unregistered builder can replace these and the building inspector will sign them off as part of the same job, hopefully saving quite a lot of money.

You shouldn't be embarrassed to ask any builder any questions about the job, and any builder who mocks you about any question with sarcastic answers, etc., should be given a wide berth, you should at all times be given an honest informed choice at all times, and at any stage of the build the builder should give an open explanation of what is going on, but please take heed, you may not like what he has to say when problems occur, but he should explain why something is required and you will not always like what he tells you when problems occur, which is all part of the process.
If you like the answer, please hit the like button, and hope this helps with the reality check in understanding the building trade .
Kindest regards

Answered 23rd Jul 2012


Member since 24 Apr 2012

Having obtained your planning permission and drawings,you are ready to post this as a job/obtain REAL quotes.Pricing by the m2 is pretty vague.You are going to have to ask builders all of these questions anyway in order to proceed so i wouldnt worry too much.Site visits by reputable builders would be the only way to achieve a fixed quote and stay within your budget.This will determine what you can and cant afford at any given time.BEWARE the builder that claims to be so good he can quote by emailed drawings.Its very hit and miss and if he cant be arsed to visit,what kind of a job are you going to get.

Answered 22nd Jul 2012

Roc builders

Member since 25 Aug 2011

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