How much detail is required before I can get a price?

Hi Ben, Your best bet is to put your drawings out to a couple of builders to price stating that steels have not been calculated at this stage..The price of steels in the scheme of things is only a small part of the total cost and there is probably more expense in the labour of putting them in than the material cost. Most builders will probably cost them as worst case scenario so your quote will reflect the most you are likely to pay...from there you can make your decisions to advance or hold fire for another time. Hope that helps.

Hi Ben Could you possibly provide me with the Drawings you have and i can try to propose you with a better price. Looking Forward hearing from you

I appreciate that there does seem a lot of cost up front, but apart from the architect's fees, everything else you are paying for is pretty standard for all extensions... and things like structural calculations and the third party checking done by your local Building Control all needs to be done by professionals who, apart from needing to get it right first time, everytime, all have insurance and professional fees to ultimately ensure that if there is a problem, YOU are not out of pocket should the worst happen. In terms of previous answers, yes they are good suggestions... but when it comes to hiring a good builder who will provide you with a good service and make the best of your hard earned money with your extension, these sorts of firms are not short of work and they have no impetus to try and help you over other potential customers who have done all their preparation work and have an 'oven ready' set of plans and specifications all ready for them so that they fully understand the scope of the build and they are able to accurately quote for the project. Short cuts in building work are rarely a good idea.

You must provide a Structural engineering design does not matter whom you give to build it for you.