Home Extension Builders in Sevenoaks

Home extension costs in Sevenoaks generally run from £40,000–£60,000 for a single-storey rear extension and £80,000–£110,000+ for double-storey projects. Sevenoaks sits in the Kent commuter belt rather than central London, so labour rates are somewhat more competitive than inner boroughs though material costs and any specialist requirements around older properties or Green Belt-adjacent sites can add to the overall figure. Buildaway provides a fully itemised quote after a free survey, broken down by trade and stage so you know exactly where the budget is going.

It depends on your property's specific location and designation. Many homes in Sevenoaks TN13 and TN14 can extend under permitted development, but Green Belt proximity, AONB overlap around the North Downs, and Sevenoaks District Council's conservation area designations in the town centre and surrounding villages can all reduce or remove those permitted rights. Properties within the Green Belt face stricter tests extensions are generally limited in scale and must not result in disproportionate additions to the original dwelling. Buildaway reviews your property's planning status at the outset and handles the correct application route, whether that's a householder application, prior approval, or a more complex Green Belt submission.

We build single-storey rear extensions, side extensions, double-storey additions, wrap-around designs, and garage conversions across the Sevenoaks area. Many properties in TN13 and TN14 sit on larger plots than typical London homes, which opens up options that aren't always feasible in more urban settings. Whether you're looking to create a bigger kitchen-diner, add a ground-floor bedroom suite, or build out a proper home office with separate access, we'll assess the site and give you a clear picture of what's structurally and planningwise achievable.

On-site construction for a single-storey extension typically takes 12–14 weeks, while double-storey projects run closer to 16–20 weeks. If planning permission is required which is more likely for Green Belt-adjacent or conservation area properties allow an additional 8–12 weeks for Sevenoaks District Council's determination process. For more straightforward permitted development projects, that wait is removed and the programme is considerably shorter. We set out a realistic schedule during the initial consultation so you're not working from vague estimates.

Yes. While detached properties in Sevenoaks sometimes avoid party wall requirements altogether, semi-detached and terrace homes particularly those closer to the town centre and station area will almost always trigger the Party Wall Act when extending to the rear or side. Buildaway manages the full notice process: identifying which neighbours need to be notified, serving the correct notices within the required timeframes, and coordinating with adjoining owners or their surveyors where a dispute arises. It's handled as part of the project rather than an extra you're left to navigate.

Yes Buildaway runs the complete project in-house. Our architects draw up the plans, our structural engineers produce the calculations, and our own trades carry out every stage of the build from groundworks through to final decoration. There's no point where the project gets handed off from a design team to a separate contractor, which is where timelines slip and accountability becomes blurry. One team handles it all, with one contract covering the full scope of works from planning submission to Building Control sign-off.

Building in Sevenoaks is generally 10–20% cheaper than equivalent projects in inner or central London boroughs, largely due to lower local labour rates. That said, any project involving Green Belt planning, heritage-sensitive materials in a conservation area, or complex groundworks on older Kent properties can close that gap. The other side of the equation is that Sevenoaks property values are strong particularly for family homes with good transport links into London so a well-executed extension adds real, measurable value to the property rather than just improving daily life.