Range from the cheapest Side return extension £37,000 (Eco Future Build based in BR6) to the dearest Side return extension £41,500 (Silverland design & build based in BR1).

Comparing extension builders estimates for Side return extension gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.

What to do - Get rates and quotes for a side return extention by posting your job to extension builders in Orpington.