Project Type
Liquid Screed for Garage Conversions
Converting a garage into a habitable room usually starts with the floor, since garage slabs sit lower and are less insulated than the rest of the house.
Converting your garage?
Get the floor build-up right from the start with an insulated, level liquid screed system.
Or call our landline on 01392 237700
Garage floors are built to a different specification from the rest of a house — typically lower, thinner, and without the insulation expected of a habitable room. Converting a garage into a playroom, home office, gym or extra bedroom therefore usually means addressing the floor build-up before anything else, and liquid screed is a practical way to do it.
We can incorporate rigid insulation boards over the existing garage slab, run underfloor heating pipework across the insulation, and then pump liquid screed over the top to create a warm, level floor that matches the height of the adjoining hallway or living room. Getting this level right is often one of the trickiest parts of a garage conversion, since the original slab can sit several steps down from the house. The typical sequence runs from slab inspection and preparation, through DPM and insulation, heating pipe installation and testing, to the screed pour and, finally, flooring once drying is confirmed.
Liquid screed's ability to flow into every corner also suits garages, which are often an awkward shape with a door opening, step, or drainage channel to work around. We assess these features during our site visit so the build-up and any infill work needed around a redundant drainage channel is priced accurately from the outset.
Solving the level difference
Garage slabs are frequently 100–150mm lower than the finished floor level of the house, partly to allow for a vehicle ramp and partly due to different original construction standards. We measure the existing levels carefully and design an insulation and screed build-up that brings the converted room up to match the adjoining hallway, avoiding an awkward step at the internal threshold.
Where the level difference is larger than insulation and screed alone can comfortably make up, we discuss options with the builder, such as raising the slab itself, rather than specifying an unusually thick screed pour that isn't the most cost-effective solution.
Insulating a previously unheated space
Because garages were never designed to be heated living space, the floor typically has little or no insulation. Introducing rigid insulation boards beneath the screed is one of the most effective ways to bring the converted room's thermal performance closer to the rest of the house, working alongside wall and roof insulation carried out elsewhere in the conversion.
We also check whether the existing slab has an adequate damp-proof membrane, since many garage slabs were built without one on the assumption the space would only ever store a car, and this needs addressing before insulation and screed go down.
Trades and building control on a garage conversion
A typical conversion sequence involves a builder handling any door infill or structural opening work, a damp-proofing specialist if needed, a heating installer, us for the insulation and screed, then plasterers, an electrician and a flooring contractor. Because the room is changing use from a garage to habitable space, building control usually requires evidence of adequate thermal performance and damp-proofing.
We keep a simple record of the insulation specification and screed depth used so this can be passed to building control or the client's own paperwork as needed.
Common pitfalls in garage conversions
One frequent issue is discovering a redundant drainage channel or inspection chamber part-way through the slab, which needs to be properly sealed or built over before insulation and screed can be laid; we flag this during the site visit wherever possible.
Another common pitfall is treating the garage door opening as an afterthought — if it isn't fully bricked up and damp-proofed before the floor build-up starts, cold and damp can bridge in at that point regardless of how well the rest of the floor is specified.
Garage Conversion — the points that decide it
- Addresses the typical garage slab height difference relative to the main house
- Insulation build-up reduces heat loss through the original garage floor
- Underfloor heating pipework easily incorporated beneath the screed
- Self-levelling flow suits awkward garage shapes, steps and door openings
- Fast-track additives available to help keep conversion programmes moving
- Smooth finish ready for a range of final floor coverings
- Damp-proofing addressed where a garage lacks an adequate original DPM
- Building control checks thermal performance since a garage becomes habitable space
- Budget mainly driven by insulation depth, level make-up and DPM upgrades
Converting your garage?
Get the floor build-up right from the start with an insulated, level liquid screed system.
Or call our landline on 01392 237700
Garage Conversion — your questions
In short
Converting a garage into a habitable room usually starts with the floor, since garage slabs sit lower and are less insulated than the rest of the house.
Converting your garage?
Get the floor build-up right from the start with an insulated, level liquid screed system.