How Long Does a House Extension Take?

The on-site construction time for a single-storey rear extension is typically 8 to 14 weeks. A two-storey extension usually takes 14 to 22 weeks. More complex designs, poor weather, or the need for groundworks can add time. Before work starts on site, there is a design, planning and approval stage. This can take a further 4 to 12 weeks depending on whether planning permission is needed and how quickly building regulation approval is obtained. At Joseph Thomas Group we prepare a detailed programme before construction starts and keep homeowners informed of progress throughout.