Who do I need to deal with extension? Moving boiler/soil pipe etc. Does an architect have knowledge of these things?

[Splandy]

Not sure how to go about doing an extension. There are a few awkward things, will have to move drains, boiler will probably need to be moved and I'm not at all sure of even the shape of the extension since there's currently a collection of brick outhouses attached to the house and many option for incorporating/knocking down etc.

Original plan was to get some architects in. Actually, I've been looking at a well reviewed architectural designer, rather than an architect. Would they have the knowledge to plan around pipes/boiler etc? Or do I need somebody else to come in and tell me what is possible?

[Ntinyn]

We had to do this too. Architect gave us general advice after examining the existing drainage etc and applied to water company for drains approval. Builder gave more practical advice after the drawing stage. A good architect will know what to do so go with your designer then get your chosen builder to look in detail and the price of build will accordingly adjusted.