Though there are many advantages to underfloor heating, some of the downsides to underfloor heating systems include that you need to replace your existing floors if you can’t access the floor joists or aren’t installing heating on concrete. Also, your floor height increases by roughly an inch when you install underfloor heating on top of the subflooring, potentially impacting your ability to close doors. There’s a high upfront cost compared to other heating options, and depending on the complexity and extent of work, installing floor heating is often a time-consuming installation process that can take a handful of days—hence the high installation costs!