- radiant heating -

when it comes to winter comfort, there is simply no comparison to heated floors.


after 16 years of enjoying radiant floor heating, Sandee and I would find it really hard to live without it. even though it added considerable cost, it was a settled matter that 340 fairfax would include warm floors.

just as with our heat pumps, we engaged a professional designer to engineer the radiant system. With reclaimed heart pine floors, the last thing we wanted was a snafu in the system design that would require cutting into or removing flooring.

our designer spouted his normal techno garb emitting words like heat flux, emissivity, pressure drop, hydraulic separation, weather responsive outdoor reset….yada yada yada…..


eventually he provided us with drawings showing a detailed layout of the tubes and identifying every circuit within the six zones. all essential components were specified. we simply followed the engineered drawings and everything fit into place.

we used what’s called a low mass system by installing radiant tubing on top of the Advantec flooring. Mr. Pex Systems, a Swedish based company known for top quality radiant heating products provided our tubing. Mr. Pex along with Caleffi, an Italian based company and Grundfos, a German manufacturer provided first-rate specialty components.

the tubes were inserted in aluminum transfer plates that spread heat evenly across the floor. this prevents hot and cold spots. plus the heat source is just ¾ inches under our toes. that’s extremely efficient and the response time is quicker than our system at Belews Lake, which was embedded in concrete.

a tiny natural gas water heater/boiler hangs on the wall in the garage. NTI Boilers in Saint John, NB manufactured this unit. It heats water for our radiant floors at 95% efficiency. just like our heat pumps, it is variable capacity and modulates the water temperature based on how cold it is outside. with our strong emphasis on insulation, air sealing and high performance windows, we only need about 105 degrees F water on the coldest winter days to be comfortable.

the NTI unit plugs into a regular electric receptacle and uses less power than a microwave. the Grundfos circulators use about half as much power as a 40-watt light bulb. that means the circulator can run non-stop for nearly 2 ½ days before we use clock a dime’s worth of electricity. the heavy lifting is really done by natural gas. but our back up generator can easily handle the electrical load. so when there’s a power failure, we still have plenty of radiant heat.

our temperature controllers determine when we need heat in the floors. it sends a message to the master controller, which opens the zone actuators and energizes two circulators. when the water heater/boiler senses flow, it fires up and heats the water. as the heated water flows through the tubes, the floor warms up and becomes a giant heating radiator.

This is no ordinary custom cabinet.

Hidden inside is another cabinet!

but wait there's something inside!

this is one of three manifolds that consolidate our radiant tubing. the white devices on top are flow actuators that open and close on a signal from the master controller when that zone needs heat.


looking closely, you can see the blue top showing on the Master Bath indicating it is open and heating the floor.

there aren’t many moving parts in this system. the water heater/boiler, two circulators and the zone actuators are about it. those components have a proven history of 25 to 30 years reliable service life.  if a circulator or actuator fails, replacement is plug and play at minimal expense.


but there is nearly ½ mile of tubing under our floors. the good news is, accelerated testing has shown Mr. Pex’s superb quality tubing will last some 300 years.  


so, we’re pretty sure our radiant floors will be heating the feet, knees and hands of our great grand children some day. we hope they will speak well of us.