Underfloor Heating – Pros, Cons And Things To Consider

Underfloor heating is often associated with luxury and well-being and is increasingly being considered as a worthwhile investment among many homeowners. Although its origins can be traced as far back as the Roman Empire, the popularity of these heating systems has only taken off in Ireland over the past decade.

If you’re considering investing in an underfloor heating system for your home, you’ll want to read through this article to familiarise yourself with the advantages, disadvantages, and key considerations of these heating systems.

The Pros

  • Energy efficiency: The thermal sensation produced by radiant heat sources like those used in underfloor systems makes people feel comfortable at lower temperatures than if they were using other heating sources. Setting the thermostat a mere degree or two lower can make a difference in your energy bill, and according to EnergyWise Ireland, underfloor systems can cut down heating costs by up to 30%.
  • A healthier indoor environment, because heat is generated and distributed differently. The heating method used by radiators is convection, where hot air is pushed or moved around a room. But warm air isn’t the only thing moved around: so are allergens like dust and mites. On the other hand, underfloor systems mostly rely on conduction and radiation as the primary methods of heat distribution – imagine having the sun under your floor. These systems don’t dry the air or aggravate allergies. 
  • Compatibility with home automation systems for optimal comfort. Home automation technology has come a long way, now making it possible to integrate it with underfloor systems so you can heat each room at the desired temperature. This can be done using WiFi thermostats or central controls that can be monitored and managed remotely via smartphone apps. 
  • Safety, because there are no open flames or hot radiators that can pose a hazard to yourself or to your home if left unattended.
  • A more enjoyable space: these systems are virtually silent and free up room that would otherwise be taken up by radiators or large heating appliances. Also, you won’t have to worry about draughts or cold spots.

The Cons

  • Installation is more complex and disruptive than fitting a radiator or getting an electric heater. This isn’t a problem in new builds, but when installing it in existing properties, the floor will need to be lifted, which involves a considerable amount of work. Retrofit installations are not a “plug-and-play” project, and will need to carefully planned if you live in the property while work is carried out.
  • In some cases, you may need to install a heat pump to replace your boiler, as pumps work better with this type of radiant heat system and are well suited to the particularities of Irish climate. Added bonus: heat pumps are cheaper to run in the long term.

  • On that note, if need to switch to an air-to-water system like a heat pump to support your underfloor installation, you’ll need to have an SEAI technical assessment to find out whether your house is ready and what upgrades are needed before going ahead. You can find a list of qualified technicians from the SEAI website. While this assessment can be pricey, grants are available under the Better Energy Homes scheme. 

  • In old homes with poor or no insulation (such as those built 30 years ago and before), the costs of getting the house ready for underfloor installations can be very high. In some cases, you may need to complement the underfloor system with other sources of heating in order to meet maximum permitted heat loss values and comply with building regulations.

Things to Consider

Underfloor systems are not a one-size-fits-all heating solution. Before you decide on undertaking a project of this scale, you’ll need to consider the following factors: the type of underfloor system that suits your needs best, flooring materials, home insulation, and overall installation cost.

  • Water-based underfloor systems: These are connected to central heating systems and rely on pipes to deliver heat across a room. As hot water is circulated through the pipes, the floor becomes a radiator in itself. Because extensive pipework is involved, water-based systems are best suited to new builds or whenever you’re laying the floor from scratch. 
  • Electric systems: These are independent from central heating, as heating wires are placed underneath the floor. Electric systems can come as ready-to-roll-out mats, so they are a better option if you’re upgrading heating system in an existing property, if floor depth is an issue, or if you’re planning to tackle the installation by yourself. 

  • Insulation: According to Irish Building Regulations (Page 17, Part L), the recommended insulation requirements for underfloor systems are equivalent to 150mm of Polyso-type insulation boards.

  • Flooring materials: Tiled or stone floors can usually support both water-based and electric systems, but vinyl and PVC floors may not be compatible. If you have wooden floors, there is a chance that boards may buckle or crack if they haven’t been designed to withstand the levels of heat generated by underfloor systems, so always check with the manufacturer paying special attention to the wood’s moisture content, overall thickness, and width-to-thickness ratio. Also, avoid beech and maple, since they have a poor tolerance to heat. 
  • Costs: Generally speaking, electric systems are cheaper to install but more expensive to run than their water-based counterparts, so they’re better suited to rooms with a small surface area. 

In addition to these considerations, it’s essential to get the right support from construction professionals who can assist through the entire process, from design to the finishing touches. This will ensure that your underfloor heating installation is a success and improves your quality of life at home.