Gary Finnie
Hi Sarah, The builder should be able to advise you on all matters relating to this. I like other builders would happily make an appointment to discuss with you in detail your requirements and arrange the architect / engineer to do drawings and submit on your behalf along with providing you with advice on procedures and cost for planning permission & build control. This would then be followed up by a full written quotation based on final design, size & internal finishings. All aspects would be taken care off up to the final sign off by build control. My website has a page which describes the planning process and build control responsibilities so have a look and feel free to call or get in touch at any time for free impartial advice. You can also look up your local council planning web site for more information. I hope this helps Kind regards Gary