Garage conversions
The cheapest square metre you will ever add to a house, provided the damp, the floor and the insulation are dealt with properly rather than boarded over.
You already own the space
An integral garage is usually the worst-used room in the house. It is already roofed, already walled and already inside the footprint. Converting it is the least disruptive way of adding a real room.
It is also the job that gets bodged most often. A stud wall in the opening, a bit of insulated board, a laminate floor over the existing slab and it is sold as a conversion. Two winters later there is damp at the base of the walls and the floor is cold.
The three things that decide whether a conversion works are the floor, the damp-proofing and the front infill. Everything else is decoration.
Six things we deal with properly
The floor
Garage slabs are usually laid low, unheated and without insulation. Where the level allows we insulate over the top; where it does not, the slab comes out and a new insulated ground-bearing floor goes in to current U-values.
Damp
External garage walls often have no DPC at the right height, and the ground outside can sit above the internal slab. That has to be dealt with before any lining goes on.
The front infill
Built as a proper cavity wall with a DPC to both leaves, an insulated cavity lintel, cavity closers and a cill DPC that sheds outwards. Not a stud wall with a bit of brick slip on it.
Insulation and cold bridging
Full insulation schedule with U-values for every element, and lining carried past the changeover to kill the flanking bridge where only part of a wall is external.
Gas, meters and services
Gas and electric meters often live in the garage. They need proper enclosure with ventilation where gas is present, and they need to stay accessible.
Ventilation and heating
Background ventilation to the new room and a heat source appropriate to the use. Both are building regulations matters, not optional extras.
Keeping half the garage
A lot of people want a utility, a study or a gym but still want somewhere for the bikes and the freezer. A partial conversion keeps the garage door and splits the space with an insulated dividing wall.
It is a slightly more technical job than a full conversion, because the dividing wall becomes a thermal element with a fire requirement, and the two halves need separate ventilation. We have standard construction details for exactly this.
- Dividing wall built as a fire-rated, insulated thermal element
- Floor build-up stepped at the changeover so levels work
- Separate ventilation to the heated and unheated sides
- Garage door retained and made good
- Meter cupboards enclosed and vented where gas is present
How a conversion runs
- SurveyMeasured survey with a written record sheet. Dimensions, existing construction, damp, gas, electrics, drainage and levels.
- Drawings and building noticePlans, sections and details produced in-house and submitted with the application.
- Trial holes and pre-startFoundation evidence gathered and the inspection stages agreed with the surveyor before we start.
- Floor and infillFloor out and rebuilt if needed, then the front infill built to cill, jambs, lintel and window in a controlled sequence.
- Linings and first fixInsulation, membranes, studwork or dot-and-dab, then electrics and any plumbing before boarding.
- Finish and sign-offPlaster, skirting, decoration to the agreed level, final inspection and completion certificate.
Things people ask us
Do I need planning permission to convert my garage?
Will I lose the parking space?
How long does it take?
Can the consumer unit stay in a cupboard?
What does it cost?
Free design, free visit, free samples
We measure up, talk it through and send a written proposal with the build-up, the programme and one whole price. No pressure and no follow-up sales calls.