Do I need some sort of spec for getting quotes or will the building regs drawings do?

[Ragusa]

Sorry, not very well phrased but what I mean is ...

We are planning an extension. We have planning permission and have had building regulations drawings done by a structural engineer.

Now we want to get some quotes in for the work and see what the damage is likely to be.

To do this and get meaningful quotes do I need to instruct a quantity surveyor to draw up some sort of building specification, or will builders be able to quote off the back of the structural engineer's detailed drawings?

We did have architectural designers doing the plans for us and they contracted the structural engineer on our behalf but for various reasons we' don't want to use them further to contract with builders and oversee the build... we've just not been that impressed with them and they've cost us a lot of money.

I don't however want to make the mistake of not doing things properly to save money.

Can someone more experienced tell me what to do please?

It's a domestic single storey rear extension by the way. Nothing complicated.

I mean I don't want to cut corners if it really would be more cost-effective in the long-run to have a specification of works drawn up.

I saw this and wondered if your average Joe would be able to fill it in meaningfully?

Anyone? :)

We just used the building regs quotes to get builder quotes. I thought it was up to the builder to use a QS if they wanted to?

Ah great, thanks Marmite. I just wasnt sure what the procedure was.

I wouldn't have thought it necessary to get a QS in for a simple single storey extension. But I would do some research about exactly what windows/ bifolds/ flooring / radiators / internal doors you would like and put that in a spec - otherwise you will not be able to compare quotes like for like - different builders will price up diff quality bifolds for example at different prices.

Also be clear on electrics and lighting - you don't want one builder quoting for 2 sockets per room and another for 4 sockets per room (particularly if you actually want 6!). These are all decisions you will need to make anyway so you are better off making them now.

IXos, thanks v much as well. We will specify to the hilt, having learned our lesson on that one during the first round ofrenovations ;)

DH did our drawings - it was a fairly simple rectangular extension.

Drawings are not an issue as they're all done already.. The verdict seems to be that a surveyor is not necessary really but that we will have to think carefully about the detail we ask for ....

standard practise in my trade would be to get a Qs to spec and price the job using BCIS or spons, and put on figs for prelims, contingency etc. then you go out to tender using the building plans and unpriced spec. Let the builders come back to you with a price for the job, then you can look at your Qs costs and see where they are in comparison and help you select your builder. The Qs will also be able to advise on the project timeframe, and issues such as access/ parking and how they might be overcome/ costs minimised. They will also be able to advise on using a minor works jct contract that you can buy off the shelf, which will accommodate a process for any changes to the spec you may decide to make during the build, so builder can't use this to crank the price up wildly. I guess your decision will depend upon the size and importance of your project, and your attitude to risk. Having used an excellent Qs on a job recently I admit to being biased but they saved my client from being ripped off as they knew every builders price enhancing trick in the book. I think the RICS just brought out a book called 'building contract for a home owner who has not appointed a consultant to oversee the work' for £24.95 might be worth a look.....the comments by ixos above completely valid, it's not only your electrics that need speccing, there's a rake of things to consider incl insulation and fire stopping...

Frogs I would be interested in the details of your QS if you were willing to PM me them. I can see what you're saying about cost control; it's really hard to know when someone's pulling the wool over your eyes if you're not in that particular trade.

Hi - Half the problem with some builds where the price then escalates is that the client thinks of things as they go along - rather than sitting down and really working out just how you want the space to work then planning for the electrics and water etc at that early stage - detailed planning makes the quotes more accurate, as they know exactly how you want the end to be/look/work like.

I'm asked nowadays to put in as much detail as we can for this kind of purpose ... basically drawing the perspectives plans and such with suggested down light positions and electric socket points, fused spurs etc so they can get all the info to their builder - really useful if you want table lamps or a charging station in odd places etc or for kitchen planning or bedrooms with walking closets that require lights and electrics etc -
... it's easier to show someone the 'look' you want to achieve in a picture than talking about it and then maybe misinterpreting what you actually meant.
Then at least you can argue that you asked for 6 plugs and show them where they should have been when they only install 4 !!
So maybe you need a concept planner rather than a list or QS ?!

Our builder stuck to his quote, so a QS would have been over-kill in our case. Our architect did do very detailed plans though, and I was fully aware of what we/the builder was supplying.