Home Extension Builders in Balham

In Balham SW12, single-storey rear extensions typically cost between £42,000 and £62,000, while double-storey additions range from £80,000 to £105,000 depending on size and specification. Balham sits in Wandsworth, where build costs are more competitive than central London boroughs but still reflect South West London labour rates. The age and condition of the property, any drainage work required, and the standard of internal finishes all influence the final figure. Buildaway provides a clear, itemised quote after a free survey so you know exactly what you are paying for.

A good number of Balham properties can extend under permitted development, particularly detached and semi-detached houses on the residential streets between Balham High Road and Tooting Bec Common. That said, Wandsworth Borough Council has designated conservation areas in parts of SW12, and properties within these boundaries cannot use permitted development for rear or side extensions. Buildaway confirms your property's planning status at the start and takes care of any application required, whether that's a prior approval notification or a full householder submission.

Balham's housing mix predominantly Edwardian and interwar semis with generous rear gardens makes it well suited to kitchen-diner rear extensions, side infill additions, and double-storey builds that add bedrooms above an extended ground floor. Many SW12 properties also have usable loft space that can be combined with a rear extension project for maximum added floor area. Buildaway surveys the plot, existing structure, and garden orientation before recommending an approach that makes practical and financial sense for your specific home.

For most Balham projects, on-site construction takes 12–14 weeks for single-storey work and 16–20 weeks for double-storey builds. Where permitted development applies, there's no planning wait and the programme starts sooner. If Wandsworth requires a full application, factor in 8–10 weeks for the council's decision. Buildaway sets out the complete timeline planning stage included at the initial consultation, so you have a realistic view of the whole process from day one rather than just the build phase.

If your property shares a boundary with a neighbour as most Balham semis and terraces do then any rear or side extension will almost certainly trigger the Party Wall Act. This means serving formal notices on adjoining owners before construction begins. Buildaway handles the entire party wall process as part of the project: drafting and serving notices, liaising with neighbours, and appointing a surveyor if an agreement needs to be drawn up. It is factored into the programme from the start rather than treated as a last-minute task.

Yes Buildaway runs the full project under one roof. Architectural drawings, structural calculations, planning submissions, Building Control applications, and every trade from groundworks through to final decoration are all handled directly by our team. There is no point where we hand the project over to a separate contractor. That continuity means the design intent carries through to the finished build, and you have a single point of contact accountable for the outcome throughout.

Balham has seen consistent buyer demand from families looking for more space without leaving South West London, which makes well-planned extensions here a reliable way to add value. A rear kitchen extension or double-storey addition on a typical SW12 semi can add significantly more to the property's market value than the build cost particularly where the result creates a proper open-plan ground floor or an extra bedroom. Buildaway gives you an honest view of the likely return during the initial consultation, based on the property type and what the local market typically values.