Heating
Wet or electric underfloor heating?
Wet systems for whole floors and new screed, electric for single rooms over an existing slab. The decision has to be made before the floor goes down.
How they differ
A wet, or hydronic, system circulates warm water through pipework laid in or under the floor, fed from a manifold connected to your boiler or heat pump. An electric system uses a resistance mat or cable connected to a thermostat.
Wet systems cost more to install and less to run. Electric systems cost very little to install and considerably more per unit of heat, because you are paying electricity rates rather than gas rates.
When to choose which
Wet is the right answer for a whole floor, an extension, or anywhere a new screed is going down anyway. It becomes the primary heat source for that space, which frees every wall from radiators.
Electric is the right answer for a single room — typically a bathroom or an en-suite — where you are retiling over an existing slab and the build-up height matters. It works as comfort heating under tile rather than as the room's main heat source.
Build-up height and floor finish
A wet system needs insulation boards, pipework and screed above the structural floor. A traditional sand-cement screed needs meaningful depth and a long cure; a liquid screed can be laid thinner and dries faster, which is often what makes the difference in a retrofit.
Floor finish matters. Tile and stone conduct heat well and suit underfloor heating best. Engineered timber is fine within the manufacturer's temperature limits. Thick carpet and underlay insulate the floor from the room, which defeats the point.
Why it has to be decided early
Underfloor heating changes floor levels, and floor levels change door heights, thresholds and stair details. Deciding after the screed is down means taking it up again.
It also suits a lower flow temperature than radiators, which is exactly what a heat pump wants. If a heat pump is anywhere in your plans for the next decade, a wet underfloor system is the decision that makes it viable later.
This guide describes national rules for England and was written to be accurate at the time of publication. Local designations can restrict them further, and legislation changes. Always confirm the position for your own address with your local planning authority, or ask us to do it in writing.
Related service: Underfloor Heating in London
Answers
Questions we get asked alongside this
Do I need planning permission for underfloor heating in London?
It depends on the property type and what is proposed. Many single-storey rear extensions and loft conversions fall under permitted development, but those rights do not apply to flats and are restricted in conservation areas or where an Article 4 direction applies. We check the planning position for your specific address before quoting, and tell you in writing which route applies.
How do you price the work?
From a site survey, written up as a fixed and itemised scope before any deposit is discussed. If something genuinely unforeseen appears once work is opened up, it is priced and agreed in writing before we continue — never added to the final invoice after the fact.
When do I pay?
In arrears of work completed. You pay for work that has been done and inspected, not for work that has been promised. This has been how the company operates since 2008.
Do you handle Party Wall notices?
Yes, where the work requires them. Under the Party Wall etc. Act 1996, notifiable work on a shared wall needs 2 months written notice to the adjoining owner, while excavation near a neighbouring structure and building at the line of junction need 1 month. We serve the notices and manage the award process as part of the job.
Will I get certificates at the end?
Yes. Electrical work is tested and certificated under Part P, and building control issues a completion certificate where an application was required. You receive the handover pack — it is what a buyer's solicitor will ask for when you eventually sell.
How long will it take?
It depends entirely on scope, and we give a programme with the written quote rather than a guess on the phone. What we will not do is start a job we cannot resource, which is the usual reason a build stalls halfway through.
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