my Old Workshop

Radiant heating for floors (Part 2)

Last time, we introduced you to radiant heating, a good way to warm up those tile floors. If you’re putting in a new floor, now’s the time to install the heating.

Remember to put a layer of insulation under the heating tubes/cables, to stop heat from escaping downward.

For both electric and hot water systems, an inch or two of concrete is usually poured around the tubing or cables. This becomes the subfloor. Concrete is the best material for radiating the heat, and for supporting your tiles, but you should make sure your framing is strong enough to support the additional weight. Check into lightweight concrete.

You can avoid using concrete altogether by using aluminum plates. You attach the tubing directly to the plates, and lie them between 1×4 sleepers. Then nail a plywood subfloor over top.

With this system, you’ll need hotter water, since the plywood insulates better than concrete; rather than absorbing and radiating the heat, it reflects it. As well, the plates don’t conduct the heat as well as the concrete, since they don’t make full contact.

If your floor is already in place, and you have access to the joists below, you may be able to install the tubing underneath the existing subfloor between the joists. You’ll use the aluminum plates system here. However nails, wiring and plumbing can get in the way, making this difficult.

If you don’t have access, don’t give up hope. If you can’t install radiant heating, position a heat lamp above the areas that are giving you cold feet. Set them on a timer to start a few minutes before your alarm goes off, and you’re set.