Dormer window based loft extension

codayoda

Living in SW London it seems decidedly troublesome to find a decent builder offering a sensible quote. Unlike other threads on MSE, I don't need a loft conversion as I already have a full top floor (with staircase, en-suite, "normal" floor and existing dormer). My desire is to add a second dormer at the rear to allow the space to be split into two rooms, with refitting of the en-suite (but still using the current waster/water plumbing).

In my non-builder brain, I'd expect a quote to be less than a loft conversion (after all there is no staircase, floor work or major plumbing changes to do). There are two steels to add, but otherwise the plans seem pretty simple (I've got lawful permitted rights confirmed and structural plans)

Yet, I've had quotes around £45k inc VAT from 3 local builders (and one at £36k from a larger company with odious gagging clause T&Cs). These seem to me excessive given its basically two steels, a dormer and making good the roof. The internal rearranging is just simple plasterboard walls and refitting the en-suite. But the question is ultimately, "is this quote fair"? (given it is SW London...)

suisidevw

Yes, seems excessive considering I'm having a full loft conv, full width dormer, hip to gable and re roof, ensuite etc for £44k! Not in SW London granted, but even.....?!

Amphion

That does sound slightly excessive IF what you have described is all you are having done. However Are there any extenuating circumstances for the high prices, is the work not straightforward to get to? Do they need to strengthen walls/ foundations to support the steel beams. Point I'm trying to make is it isn't always as simple as throwing in a few steel beams, cutting/building dormer and making good. There may be a lot of strengthening work needed to transfer the loads safely to the foundations.

Firstly Ask for a breakdown of the cost. Is it including vat or is vat on top of the quote. Have them split the quote in to labour cost and material quantities and costs and ask how many days the job will take. This way it's clearer to you where the costs are coming from.
Expect tradesmen to be between 250 and 400 a day and between 100 and 150 a day for a labourer. When you get material costs phone local suppliers and compare the prices your builder is charging (keep in mind that builders will normally add 15% markup to the cost of materials).

Good luck....

codayoda

Thanks for the thoughts, no strengthening of walls or foundations needed/included, but VAT is. I'll try and get a breakdown to see what is going on.