Garage conversion openings · Westminster
Garage conversion openings in Westminster
Garage conversion openings in Westminster, from free survey to completion certificate.
- Survey, design and installation in one
- Covering SW1, W1, WC2
- Inspected before it is covered
- Free survey visit
- Engineer's calculations arranged
- Building control handled
- Fixed written price once scope is agreed
- England, Wales, mainland Scotland & NI
What garage conversion openings involve in Westminster
Planning garage conversion openings in Westminster? Our team covers SW1, W1 and WC2 and the streets around them. We also cover the surrounding towns and villages in London. You get one written quote for the calculations, approvals, propping, steel and making good.
Converting a garage is a popular way to add a room without extending. Structurally, two things usually happen: the big garage door opening is filled in with a wall, window or door on proper foundations, and a doorway or wider opening is formed through the wall between the garage and the house.
What to expect
- Forming a doorway from the house into the converted garage often goes through a load-bearing wall, especially the original external wall of the house where the garage is attached. That opening needs a lintel or beam designed by the engineer.
- The beam or lintel over a garage door was designed to span an open gap. It may be timber, concrete or steel, and in older houses it can be undersized or corroded, so the engineer checks it before anything is built underneath or above it.
- An integral garage is usually separated from the house by fire-resisting construction. If part of it stays as a garage or store, that separation must be kept, and any new door between garage and house normally needs to be a fire door.
- Most garage conversions do not need planning permission, but some estates have conditions removing permitted development rights for garages, and listed buildings or flats need consent. Changing the front elevation can also need permission in some areas.
- Garage floors often sit lower than the house floor and may have no damp-proof membrane. The infill wall needs a damp-proof course linked to the existing walls, and the floor usually needs a membrane, insulation and screed raised to the house level.
Four stages, one team
Free visit
A short visit to Westminster to see the job, agree what you want and check the bearings, floors and services that affect the design.
Calculations
The engineer's calculations and a simple drawing are prepared for your opening and shared with you before anything is ordered.
Building control
We submit a building notice or full plans application to the local council's building control team, so approval is in place before the wall is touched.
Steel in, made good
On site we prop, open up, fit and pack the steel, then fire protect, box in and plaster once the inspection is done.
How much should I budget in Westminster?
As a guide, budget £1,300–£3,850 including VAT for garage door opening infill (structural part) in Westminster, based on published UK cost guides adjusted for London prices (+28%).
| Job | Typical guide range | What it usually covers |
|---|---|---|
| Garage door opening infill (structural part) | £1,300–£3,850 | Beam or lintel checked or replaced, foundation and infill wall for the old door opening (window and finishes extra) |
| Structural calculations for a beam | £320–£960 | Site measure or photos, beam and padstone design and calculations for building control |
| Steel beam replacement | £2,550–£7,050 | Propping, removing the failed beam, new steel on proper bearings, approval and making good |
| Lintel replacement | £510–£1,540 per lintel | Propping, removing the old lintel, new lintel set on beds and brickwork made good |
Figures include our approximate regional adjustment for London prices (+28%) and are rounded. How these figures are worked out.
Building rules for Westminster
In England, taking out a load-bearing wall or putting in a beam is building work under the Building Regulations 2010. It needs approval from building control, either the local council's building control team or a registered building control approver, through a full plans application or a building notice. Part A covers the structure and Part B covers fire safety, which is why steel in homes is usually fire protected.
Terraced and semi-detached homes often need party wall notices, because cutting into a shared wall to take a beam end is notifiable under the Party Wall etc. Act 1996. Allow at least two months for the notice period unless your neighbour agrees sooner.
Local questions answered
Can I stay at home while the work is done in Westminster?
Usually, yes. The work area is screened and floors are protected. The rooms either side of the opening are out of action for a few days, and there is some noise and dust while the masonry comes out.
Do you also work near Westminster?
Yes. We also cover nearby towns including Pimlico, Chelsea, Battersea and Brixton.
How long do the structural works for a garage conversion take?
Typically one to two weeks for the structural stage: digging and concreting the infill foundation, building the infill wall, and forming any new opening into the house. Building control inspections fit around these stages, and the insulation, electrics, plastering and flooring of the conversion follow on afterwards.
Can I knock through from my garage into the kitchen?
Usually, yes. The wall between an attached or integral garage and the house is often load-bearing, so the opening needs a lintel or steel beam designed by a structural engineer and approved by building control. If any of the garage stays as storage, the opening needs fire separation, such as a fire door.
Does the infill wall need foundations?
Yes. A new masonry wall across the garage door opening needs a proper footing, as the existing garage slab is usually not designed to carry it. A trench is dug across the opening and a foundation is formed to the engineer's and building control's requirements, then inspected before the wall is built.