Radiant Floor Heating

The installation of a radiant heating system is not exactly cheap - so before we started building the house, we thought long and hard about adding it or not. Eventually, we decided to put radiant floor heat into the basement - the upstairs will be a forced air system.

The rough-in for the radiant floor heat has to be put down after the gravel for the basement floor is put in, but (obviously) before the concrete for the basement floor is poured. The radiant floor system in our basement is hydronic, meaning that it is a series of tubes that are filled with hot water. The hot water in the tubes circulates throughout the concrete floor, warming the concrete, which then radiates heat into the living space.

There are several advantages of a radiant floor system. First, they are more efficient to run (which means savings on utility bills). Second, they are more comfortable than a forced air system, because the heat source is down by your feet (where you want it). Last, there is a more consistent temperature throughout the room, since the heat source is everywhere, not in just a few locations. If you do a search on the web for radiant floor heat, you will find loads of information about its advantages as a heating system.

In our current house, the basement is never completely comfortable in the winter time (i.e. it is always a bit too cold), and since we use our basement a lot, I wanted to make sure in this house we did not have the same problem.

During the installation, the builder asked if we wanted to add radiant heat to the basement area under the garage (that we will be using as a workshop). Initially, I had not planned to do this. Although this adds about 20% to the cost of the installation, we decided to add it. With a heat source in this room, not only will it make the workshop much more comfortable, but it will make it so that the space could someday be finished off into living space (for a playroom, media room, etc.)

Some radiant floor systems are "fed" directly from a hot water heater. In our case, we will be adding a dedicated boiler that will supply the system. Again, although there is an additional cost for this, it allows the system to run more efficiently (reducing monthly costs). The boiler will be installed at a later time - at the same time the hot water heaters for the plumbing systems are installed.

The system installation starts by laying down a mat with a foil face and plastic "bubbles" filled with air (similar to what you see in packaging material). The foil facing is designed to reflect the radiant heat back up, and the bubbles are to make the reflection of heat more efficient. Then, a steel grid is set down which provides a place to tie the tubes to (so they stay in place), and also adds strength to the concrete.

The tubing is broken out into several different zones so that we can turn some areas off when they are not in use (for example, a guest bedroom). The tubes snake around the entire floor (except in the mechanical room, under the stairs, and under load bearing walls) and are evenly spaced.