At Prohaus, a larger renovation or conversion starts from £100,000 plus VAT (guide price reviewed September 2026). A whole-house renovation usually includes some combination of structural alterations, rewiring, replumbing and heating, new kitchen and bathrooms, plastering, joinery, windows and decorating, and often an extension or loft conversion. The final cost depends on the size and condition of the house, how much of the layout changes, and the specification. Period houses need a contingency for conditions hidden behind walls and floors.
Key takeaways
- A whole-house renovation is a sequence of trades. Coordinating them is as important as the price of each.
- The condition of the existing house, especially wiring, plumbing, roof and structure, sets the baseline cost.
- Layout changes and specification move the price more than floor area does.
- Keep a contingency for Victorian and Edwardian houses.
- Get one itemised quote that covers the full programme.
01What does a whole-house renovation include?
Every project is different, but a full renovation usually works through these stages:
| Stage | Typical work |
|---|---|
| Strip-out | Removing old kitchens, bathrooms, finishes and, where needed, ceilings and floors |
| Structure | Removing walls with steel beams, repairing joists, chimney breast removal, underpinning where required |
| Roof and envelope | Roof repairs, windows, damp issues |
| First fix services | New wiring, plumbing, heating pipework, data |
| Plastering and floors | Re-plastering, levelling and new floors |
| Kitchen and bathrooms | Installation of kitchen, bathrooms and cloakroom |
| Second fix and joinery | Doors, skirting, staircases, fitted storage |
| Decorating and handover | Decorating, snagging, certificates |
Swipe the table sideways to see every column.
Prohaus coordinates structural, carpentry, plumbing, electrical, tiling and decorating trades under one project plan. Gas and electrical work is carried out and certified by appropriately registered subcontractors. See our home renovations and conversions service.
02What drives the cost?
Condition of the house
A house that needs a full rewire, new heating, a new roof covering and damp treatment costs much more to renovate than one with sound services. A survey before buying, or a detailed site visit before pricing, shows where the money will go.
How much the layout changes
Repainting and re-flooring is cheap compared with moving walls, stairs and bathrooms. Every moved wall can involve steel, building control, services and making good.
Extensions and lofts
Many whole-house renovations include a rear or side return extension or a loft conversion. These are priced as part of the programme.
Specification
Kitchens, bathrooms, flooring, windows and joinery can each vary by tens of thousands of pounds depending on what you choose. Fix the specification before the quote to avoid provisional sums.
Period details
Restoring cornicing, fireplaces, panelled doors and timber sash windows takes skilled time. Replacing them with matching new work is often expected in conservation areas. See our timber sash windows guide.
04Should I live in the house during a full renovation?
For a full rewire, replumb and structural work, most families move out for at least part of the programme. It shortens the programme, reduces risk and is safer. Read our guide to living at home during building work.
05Example: Upper Richmond Road, Putney
At Upper Richmond Road in Putney, Prohaus built a full-width rear extension to a large family house and renovated the house throughout, including oak floors, a suspended fireplace, panelled bedrooms and feature bathrooms. See the project on our Putney page.
06How to budget for a whole-house renovation
- Get a detailed survey of structure, roof, damp and services.
- Decide the layout with an architect or designer before pricing. Prohaus works with professional architects and designers through our planning and design service.
- Fix the specification for kitchen, bathrooms, floors and joinery.
- Get an itemised quotation covering every stage.
- Add professional fees, approvals and VAT.
- Keep a contingency for hidden conditions.
- Agree the programme and payment stages in a written contract.
07Frequently asked questions
How much does it cost to renovate a house in London?
At Prohaus, larger renovations and conversions start from £100,000 plus VAT. The total depends on the size and condition of the house, layout changes and specification.
Is it cheaper to renovate in phases?
Phasing spreads the cost but usually increases the total, because trades return, finished areas get disturbed and set-up costs repeat. If you phase, do the structural and services work first.
Do I need planning permission for a renovation?
Internal work usually does not need planning permission unless the house is listed. Extensions, loft conversions and external changes may. Building regulations apply to structural work, new bathrooms, rewiring and more.
How long does a whole-house renovation take?
It depends on scope. Ask for a written programme with any quotation.
What certificates should I get at the end?
Building control completion certificates, electrical installation certificates, gas safety records for new gas work, and any window installation certificates. Keep them for when you sell.
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About Prohaus
Prohaus Ltd is a building company based in Kingston upon Thames, registered in 2015 and built on more than 20 years of residential building experience. We carry out extensions, loft conversions, renovations, new builds, kitchens and bathrooms, glazing, bespoke joinery and garden offices across Kingston, Surbiton, Richmond, Barnes, Putney, Fulham, Chelsea, Clapham and Wimbledon. Every project runs under a written contract with a 1-year guarantee.
Talk to us about your renovation
Send the address, photos, any survey and an outline of what you want to change. We will visit and provide a written, itemised quotation for the full programme.
