Building Regulations

Your planned extension, whatever size it may be, will not be lawful unless it has Building Regulations Approval. Building Regulations are minimum standards that all buildings, including extensions, are built to. They ensure that the buildings are safe to live in and use, as well as helping to conserve fuel and power.

Your architect will produce and submit a set of drawings and documentation to Building Control. Getting approval can take up to 8 weeks and your architect will oversee and manage this process. A Building Control Officer will check that your design complies with the Building Regulations Standards and will liaise with your architect as necessary. During the building of your extension, your site will be inspected by a Building Control Officer to check that your extension is being built to the correct standards.

There is a fee payable to the Local Authority on submission of your designs to Building Control. Current Cornwall Council Building Control charges for extensions are likely to be between £350 (inc. VAT) and £730 (inc. VAT) dependent on size.
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At 3HW, we offer a combined Planning Permission and Building Regulations application service for extensions. For this, we produce a package of drawings and documentation for both applications which we submit simultaneously. This speeds up the process, reduces the likely architect’s fee and allows to you progress to the next stage as quickly as possible. These drawings and documents will also give the builder enough information to provide accurate quotes and to build to. Our fees for this service start at £2500 (plus VAT). We will advise you as to whether this service is appropriate for you.