Matching floor heights for heated Potters Bar extensions
Put heating into a new extension on a semi and its floor still has to finish flush with the original rooms. That fixes the total depth, and everything has to fit inside it: insulation, the pipes, and the screed with enough cover over them.
Start with the cover. With liquid, 25mm above the pipes is the minimum, so the screed usually ends up 45 to 50mm thick. Sand and cement asks for about 45mm of cover, making the whole layer deeper. In a tight space the thinner liquid build-up leaves more room for insulation, which matters because without it the heat drains into the ground.
Where the heating continues into the existing kitchen, the original floor usually has to come out. Taking it up also deals with the old problems these houses can have, such as a missing damp proof membrane or a floor that has settled. The new build-up then runs through the extension and the kitchen at one level.
Flowing screed has another advantage around the pipes. Poured round the pipes, it leaves no trapped air, so warmth travels evenly and the floor heats up quicker. Ahead of pouring we look over the insulation, the membrane and the edge strip, and bring any that are missing. Before any of that, measure the room: the available depth decides the system. Our screed thickness guide sets out the depths, and insulation and membrane preparation covers the layers below.
Heating up new floors near Dugdale Hill and The Avenue
The new homes planned for the High Street and the garden suburb sites west of Dugdale Hill and off The Avenue are the kind of schemes where liquid screed over underfloor heating is commonly used. For a site team, the screed programme and the heat-up schedule need to fit together across many plots.
The rules are the same on one plot or fifty. Heat can usually go into calcium sulphate from day 7 after the pour, but sand and cement must wait 21 days or more. After that, the temperature rises gradually, is held, and comes down before flooring. Rushing it can crack the screed, and a cracked heated floor is costly to open up again. We hand over the schedule in writing for the heating engineer and flooring contractor.
Expect £20 to £35 per m² for liquid screed over a heated floor, going by the 2026 published range. Single extensions follow the same steps on a smaller scale, and the heating engineer should keep a record of each stage. For pumped access to upper floors, see our pumped liquid screed page, and for nearby towns, read about underfloor heating screed in Barnet.
Underfloor Heating Screed prices in Potters Bar
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 Potters Bar
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 Potters Bar
As the crow flies, our yard in Slough is about 22.5 miles from Potters Bar, which lies to the east-north-east. Postcodes here include EN6, and Borehamwood (4.1 miles), Hatfield (5 miles), Enfield (5.6 miles) and Barnet (5.7 miles) are close by.
More on underfloor heating screed, part of our screeding services.
