Fitting heated floors into post-war Swanley houses
Houses built between 1945 and 1972 make up 41% of Swanley's homes, and a floor of that age was not built with heating pipes in mind. Insulation, pipework and screed all have to squeeze into the depth of the old floor, and the new surface must still line up with door thresholds, the bottom stair and the base of the kitchen units.
The screed choice makes a real difference here. Pumped liquid needs 25mm or more above the pipework, bringing the floor to roughly 45 to 50mm on top of the insulation. Being runny, it wraps each pipe without leaving air gaps, and its slimmer section heats through more quickly. Sand and cement is bulkier, needing roughly 45mm above the pipework, which adds weight and depth.
Where the height is very tight, the old slab may need breaking out and lowering. That is a decision for before the heating is ordered, and our screed thickness guide shows how the layers add up.
In a new extension the job is simpler. The groundworker can set the slab low enough for insulation, pipes and screed from the start, and the new heated floor is levelled to the old one at the doorway.
On the day we arrive, we expect the insulation, membrane and perimeter strip to be down, and the pipes clipped and pressure tested. If they are not part of the heating package, we can supply the insulation and membranes.
Heating up a new screed in Swanley safely
The first weeks decide whether a heated floor lasts. Switch it on too early or too hot and the screed can crack as it shrinks.
Calcium sulphate liquid can normally take heat from around day 7, with the flow temperature kept low at first and lifted bit by bit over the days after. Sand and cement is different: no heating at all for the first 21 days. We hand over a commissioning schedule with the job, and the heating engineer runs the system to it.
The heat-up also helps drying, but it is not a shortcut. Lay the floor finish only once a moisture reading confirms the screed is dry, and be strictest about that with wood or vinyl.
For a pumped screed over pipes in an open-plan room, read about liquid screed in Swanley. If the heated room is a wet room, a sand and cement floor laid to a fall is the safer base. The same heating screed work is offered in Bexley.
One more point is worth settling early. If the heated floor will take engineered wood or LVT, check the flooring maker's limits on surface temperature and moisture before the heating goes on for the first time, so the schedule suits both the screed and the finish.
Underfloor Heating Screed prices in Swanley
Liquid screed over underfloor heating: £20 to £35 per m² supplied and laid (trade2base, June 2026), so £700 to £1,230 for 35 m². trade2base gives these figures excluding VAT. See our floor screeding cost guide or screed calculator.
Who lays your underfloor heating screed in Swanley
K & B Screeding’s own team, led by director Donatas Bardisevicius. Founded 2019, company 12298780.
See what customers say in our Google reviews and on our testimonials page.
Underfloor Heating Screed from Slough to Swanley
As the crow flies, our yard in Slough is about 36.5 miles from Swanley, which lies to the east-south-east. Postcodes here include BR8, and Bexley (4.4 miles), Dartford (5.2 miles), Bromley (5.5 miles) and Swanscombe (6.2 miles) are close by.
More on underfloor heating screed, part of our screeding services.
