Extension & Renovation Specialists in Sidcup & South East London

Ashcroft Construction Group Ltd is an extension and home improvement specialist based in Sidcup, serving London, Kent and the surrounding areas. We are run by construction professionals with 30 years of experience across the team, and we deliver a complete, turn-key solution for residential, and some commercial - projects, managing every stage in-house from design and planning through procurement, construction and project supervision.

That one-stop approach removes the need for you to separately appoint an architect, a structural engineer or other specialists. We coordinate all of it under one roof, which saves both time and cost, and it means there is nobody to point at when a detail needs resolving. If you value quality workmanship, professionalism and the certainty that your project will be completed to the highest standard, that is the service we are built around.

Our principals are members of the Chartered Association of Building Engineers (CABE) and follow its codes of practice and ethical standards. Where specialist trades are required, electrical work, plumbing, heating and gas, we appoint vetted subcontractors who hold the relevant accreditations themselves, NICEIC or NAPIT for electrical work and Gas Safe for gas, and we coordinate them into the build programme so certification arrives with completion rather than weeks after it.

Extensions that suit the house they join

Most of our work is residential extension and loft conversion projects: single-storey rear extensions that open a kitchen into the garden, wraparound extensions that square off a tired ground floor, double-storey extensions that add a bedroom above new living space, and loft conversions that turn wasted roof space into a proper room with an en-suite. The design decisions that matter are rarely the obvious ones, glazing lines, roof form, where light lands at four in the afternoon, and how the new brickwork ties into the old.

We survey the property before designing anything, then set out the planning route, whether that is permitted development or a full application. You see layout options and understand the structural approach before money is committed to a build. Where the work involves removing load-bearing walls, forming new openings or strengthening floors, the structural detailing is produced in-house and inspected by building control as the work proceeds.

Clear communication is the service

Read our Google reviews and the same words keep appearing: communication, detail, on time. Clients tell us the difference is knowing what is happening next week rather than just this week, and having one number to call when a question comes up. That is why project supervision is a formal stage of our process rather than something we do if there is time.

We also handle the parts homeowners least enjoy. Building control liaison, inspection bookings, scheduling of accredited trades and the sequencing that stops a plasterer arriving before an electrician has finished, those are our problem, not yours. Our attention to detail, clear communication and commitment to delivering projects on time and to a high standard are why so many of our clients continue to trust and recommend us.

Where we work

From our Sidcup base we work throughout Bexley, Bexleyheath, Welling, Blackfen, Crayford, Dartford, South East London and the wider Kent area. Being local matters on a build: we can get to site quickly, our trades know the housing stock, and we stand behind work in the area we live in. If you are looking for solid workmanship delivered by highly skilled tradesmen with a professional service from start to finish, we would love to hear from you.