Before We Start, How Much Will it Cost?
PLANNING STAGE
Almost all the design takes place at this stage. The image above, which is of the 3D model of a real house extension project, was done during the early design stage, to give my clients an idea of the way the extension would look from the inside. The Local Authority Planning Department are maiinly interested in how the building will look from the outside, particularly in the context of its neighbours, but this aboility to provide 3D views from any point is able to set the Planning and Conservation Officers' minds at rest that it won't be a 'carbuncle'. And there is NO EXTRA CHARGE from me - drawing in 3D is quicker than normal CAD and the plans and elevations are generated automatically at the end. I have a set SCALE OF FEES which I consistently charge everyone, and it's based on the floor area of the new building. When I give give you a quotation I'll set this out.
BUDGET FOR:
My Architect's Fee (as advised) PLUS about half as much again to cover Bat Specialists, Tree Specialists, Surveys and the Local Authority's charges.
BUILDING REGULATIONS AND CONTRACT
In the UK the tecnichal approval of structure, energy use, damp proofing and so on is done seperately from planning. The drawings for this are priceable by builders so you can get firm prices from several to check you are getting good value. The building contract is between you and the builder, but I will write the terms of it. It will include a retention clause to make sure they finish on time - very important.
BUDGET FOR:
Fees for the Architect and Structural Engineer - about the same as for Planning, or at lot less if you have a trusted builder already lined up.
You do not pay the builder anything yet - all your costs are design.
Construction
Nearly every time I see a 'building nightmare' it is because there is no written contract at all. There is no reason why you can't be your own contract administrator, but a lot of people would prefer the architect (or a surveyor) to handle the process of checking the builder is building things properly and then issuing a monthly valuation of the work, including what the Engineer has designed.
BUDGET FOR:
The cost of the build itself - £2000 a square metre is a ballpark figure.
The fees could range from nothing (you trust the buider and are doing it all yourself) to a full service at about half the Planning Fee.