Builder wanting more money.

I don't know what we are supposed to do. I do feel for people who come here with problems like this on the first post, but the key to not letting this happen is to not create room for it to happen. I wish people came and read first. We say it enough

No one loves paperwork when it comes to an exiting new building, but if you don't create a written specification to work to and the builder doesn't provide a half decent quote then where else is it going to go but into misunderstanding?

If a kitchen isn't included, I certainly wouldn't expect a worktop to be included in the price. It's part of the kitchen. You have to include it in your spec. Flooring isn't on 'plans' (quoted against), so how was the price point agreed for the flooring? What log burner did you agree on? What budget was out in for it? Who was supplying the shower room? What spec? A shower tray cost less in materials and labour than a wet room, for example, so how is the cost decided without an initial specification?

You can't do things verbally. Neither of you. It sounds like you both have compeletely different expectations. If it's written down, there's nothing to argue over. Building plans contain the bare basics of a building. No finishes.

I suggest you either sit down together and go through the costs properly, like you should have at the beginning, or you get a RICS surveyor in with some soecialism in arbitration and get this job valued properly; both what has been done and what is left to do.

How large are your extensions in square metres each? What was your initial quote?

Just to add the previous excellent advice.

The process of valuing the work completed so far and any additional work can be quite technical but you should be able to prepare your own preliminary valuation to get an idea where you stand.

It is a matter of systematically going through the quotation and assessing how much of the work has been completed, usually expressed as a percentage. How much detail you go in to will depend on how detailed the quotation is.

If as you say the quotation is quite "fluffy" we could be looking at "Build extension in accordance with plans - £50,000 + VAT" in which case you have to make an assessment on how much of the work has been completed. Say 75% of the work has been complete you should have paid the builder £37,500 less any retention if applicable so probably more like £35,625.

When you have "extras" things get more interesting, people have written books on this one subject. Technically the builder can only claim for extras for things that could not have been seen at the time of the quotation or extra things the customer has asked for that were not on the original plans.

So having to dig foundations deeper due to unforeseen ground conditions could well be a legitimate claim. However, valuing that extra is done on a pro-rata basis so the rate in the quotation is applied to the extra work, the builder cannot just pluck a figure out of the air. Often builders will try to claim for extras they "didn't allow for" in the quote. This is rather naughty, if it was shown on the plans and would have been visible and reasonable at the time of preparing the quote then it is deemed to have been included in the quote and cannot be charged as an extra. Sometimes builders will write in to a quote certain items that are excluded which is fine or it may be a genuine mistake where the builder just forgot to include it in which case it is up to you if you believe them and want to pay it.

Extra items that the customer asks for during the work can be a minefield. Ideally such changes should be avoided as they are nearly always far more expensive than the quoted work. If you really do need to make changes try to make sure they are confirmed in writing and try to get the price agreed before the work is done. Trying to go back and value extras after the event is very difficult, it should be done on the pro-rata basis as mentioned above but usually ends up a bit of horse trading. Also the builders often "forget" to give the price reductions for work that has been omitted or savings where work has been changed.

If in doubt employ a quantity surveyor to value the work and agree payments.