Top 8 questions about installing underfloor heating in older homes

Tired of radiators taking up wall space? Want a more even heat? It might be time to consider underfloor heating. It’s not the preserve of brand new homes, with cosy warmth underfoot possible in older properties thanks to the latest retrofitting technology. We’ve answered the most common questions relating to underfloor heating in older properties.

Will I have to dig up my floors to install underfloor heating?

Integrated underfloor heating is the type usually associated with digging up floors. This can involve breaking up a concrete, tile or cement sub floor, installing the heating system and relaying the sub floor. It is possible to chisel out channels for pipes in solid sub floors but there will be a lack of insulation and a loss of heat. 

Modern underfloor heating, however, means there is no need for any serious digging or excavation work. Overlay underfloor heating is placed on top of the sub floor, which is usually timber floorboards, concrete or tiles. All that needs removing is the floorcovering and any underlay. 

The process of installing overlay underfloor heating is relatively simple as long as the sub floor is level – something that can be achieved with a screed layer. Additionally, overlay underfloor heating is also available in very thin options that don’t affect headroom.

The property has timber joist flooring, can I install underfloor heating?

Timber flooring found in older properties can be a good match with underfloor heating, as the pipes can be laid in the cavities between the joists. If this route is chosen, air circulation and damp checks will be required, as will insulation. 

What’s the difference between wet and dry underfloor heating?

Wet underfloor heating involves pipes being laid, through which warm water flows – powered by a central heating or air source heat pump. There is no water involved in dry underfloor heating – instead electricity flows through laid cables to produce heat. 

Can I install underfloor heating on a first floor?

Yes, it is possible to retrofit both wet and dry underfloor heating on all levels of a property, not just the ground floor.

Does underfloor heating work with carpets?

It’s worth checking what floorcoverings each underfloor heating system works with. Some, but not all, are compatible with carpets but most work with laminate, wood, tiles and vinyl.

Is underfloor heating expensive to install in older properties?

This depends on the type of underfloor heating. As such, Checkatrade’s most recent figures reveal electric underfloor heating costs £60 - £85 per m²  to retrofit, while a wet underfloor heating system will cost £95 - £110 per m²  to retrofit.

Is underfloor heating expensive to run?

In its crudest form, gas is currently cheaper than electricity. Checkatrade found electric underfloor heating running costs are £0.12 per hour for a small bathroom (5m²) or up to around £0.49 per hour for a 20m² lounge. This compares to wet underfloor heating running costs of £0.07 per hour for a small bathroom (5m²) or up to around £0.26 per hour for a 20m² lounge. Checkatrade’s underfloor heating guide has more in-depth cost advice.

What happens if there’s a leak?

A leak in wet underfloor heating may present itself as a drop in pressure or as a watermark on a ceiling. You may also start smelling a musty, damp odour. If you suspect a leak, call in a heating engineer or plumber experienced in underfloor heating. There are non-invasive ways of detecting a leak but what happens next depends on the type of underfloor heating installed. Overlay heating may require the floor covering to be removed, while a leak within the sub floor may require localised excavation work.

As with all jobs involving plumbing, gas and/or electrics, we recommend using a registered and recommended trade to install underfloor heating. 

If you’d like to chat about your property plans, especially if you aspire to move, please get in touch.