I don't often run into radiant floor heating.
In this house the buyers asked me if I checked the radiant floor heating in the upper-floor master bathroom.
It had been turned on before I arrived. Not knowing there was radiant floor heating there, when I entered the bathroom I sure could tell!
The heating material was all over the bathroom. And it was quite uniform except immediately around the edges of the walls.
Not only could I feel it, I could see it.
Well, Mighty Mo, my thermal camera, could see it. Without the camera one can only feel heat.
And walking in the heat was on!
Taking a couple of points of temperature reference I thought would be indicative, you can see the difference between where the flooring heating material is and where it is not.
So, in this bathroom, if you have the heat on and are using the toilet, your frontey is warm and your hiney is cool!
I bet this will be a popular spot in the dead of winter!
After being in the bathroom for a while I felt like I wanted to take a nap! No one will want to wear shoes or slippers in this bathroom!
But - since we were talking about the hiney there must be a but...
Is radiant flooring an energy saver? Studies vary but seem to agree that there is no evidence for that. In fact, it appears that this heating system proves more expensive than hoped.
The system is slow to warm up and slow to cool down. Lots of heat is lost to surrounding areas, and when it is operational the flooring is warm for only a few hours a day. When the system is turned down or off the floor gets cold.
People complain that when they walk into a room the floor doesn't feel warm. So the tendency is to turn up the thermostat a bit to warm it up. That takes a while.
How long it stays warm depends on lots of things - primarily how well the insulation is done nearby. Is the "building envelope" tight? Is there infiltration and exfiltration of air through the exterior walls, doors or windows nearby? How well is the heat contained by the flooring material? There are MANY things that can contribute to the effectiveness of the heating.
My recommendation: according to the studies, it seems the floor isn't comfortable unless it is warm to the touch. Most people have skin temperature in the upper 80sF. Temperature to the touch is considered tepid, meaning comfortably warm, at 80-85F. Having to keep this floor at that temperature range all winter might be expensive. Only living with the system - experimenting with temperatures and comfort - will prove that! We don't know what we know until we know. Like, um, I mean, like, you know?
Jay Markanich Real Estate Inspections, LLC
Based in Bristow, serving all of Northern Virginia.
Office (703) 330-6388 Cell (703) 585-7560