House Extensions in Billericay & Essex
More space without the stress of moving. We design, gain approval for, and build single-storey extensions, garden room extensions and link extensions across Billericay and Essex. One team handles everything, from first sketch to finished room.
Free consultation · 3D design · Planning & building regulations handled · Fully insured
Prefer to talk? Call Martin on 07989 446768
Extensions we build
We build single-storey rear and side extensions for bigger kitchens, dining and living space; garden room extensions with large glazed doors and gables that bring the garden into the house; and link extensions joining the house to a garage or outbuilding. Before anything is built, we model your extension in 3D so you can see the space, light and layout. Changes are easy at this stage and costly later.
Design, planning and build in one place
Design and drawings by Martin, from first sketch to final plans
Planning applications prepared and submitted for you
Building regulations approval and inspections managed
Groundworks, structure and finishing by one team
One point of contact from start to finish
How much does an extension cost?
Extension costs depend on size, structure and finish. After a free site visit you'll receive a detailed, itemised quote, so you can see exactly where the money goes. See products and pricing
Your local design and build team
Molyneaux Design and Build is run by founder Martin Molyneaux in Billericay. After 20 years in engineering and project management, Martin designs every building himself and runs every project, so you'll deal with the same person from the first conversation to handover.
Do extensions need planning permission?
Some single-storey extensions fall under permitted development; others need full planning permission. All extensions need building regulations approval. We prepare and submit the drawings and manage the process for you — see our regulations guide for more detail.
Areas we cover
We cover most of Essex, including Billericay, Brentwood, Shenfield, Ingatestone, Chelmsford, Wickford, Basildon, Stock and Rayleigh.
Ready to talk about your project?
Book a free, no-obligation design consultation and site visit, or call Martin on 07989 446768.