We are renting a home with hydronic radiant floor heat and recently started it up for the season. It's not a small decision, as the system is slow to heat up and slower to cool down. So, even though we were anxious to try it out, we waited until the outdoor temperature was consistently getting down near the 30's...
It took about 24 hours to reach the full thermostat setting. Now that it's on, the radiant floors keep the home interior at a constant 70 degrees. The advantages we've noticed in the first week of use (we're used to heat by steam radiators in our Brooklyn apartment):
- The heat source is invisible. Tubing is laid into the concrete floors and carries hot water through it, warming the slab, and thus, the space.
- The system is silent: no hammering radiators or swooshing air.
- The heat is comfortable. There is a slight, consistent warmth underfoot throughout the house.
- The system is clean. It is a fully closed loop of hot water pumped underfloor. No dusty ductwork or harmful dry air.
- They system is efficient. Water holds heat well and we're expecting to see the results in the propane bill (the boiler that heats the floor system is fueled by propane). Also, the heat source is the floor itself, so the heat starts low and slowly rises up, warming you where you need it.
All of our raving is not to say the system doesn't have its drawbacks. It has high initial installation costs (though since we're renting, we didn't encounter this). And you must plan for its use. It's not at all instant heat. We kept an eye on the forecast for several days and waited out turning it on until it seemed absolutely necessary. For this reason, it can help to have a forced air backup system to provide heat during transitional periods.
We do feel the advantages by far outweigh the drawbacks and can't wait to install a similar system in our own home one day. To learn more about hydronic radiant floor heat, see radiant-floor-heating.com. Image: Lowes
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I love heated floors. I lived in Korea for 2 years and this is a standard feature in EVERY home. No more cold feet and lying on the floor is very comfortable. Sometimes the apartment would get too hot, so we would have to open a couple of windows to cool the place down. I wish it were a common thing here.
I'd love to have radiant heat, even if just in my bathroom. I've heard that you can actually set the temp a bit lower than you would another heat source because warm feet tend to equal warm body. Is this true?
The other day my husband said to me "you know what I miss? I miss the sound of the radiator in your old apartment." I haven't lived there for 10 years! Funny how we get used to some things and come to love them.
"For this reason, it can help to have a forced air backup system to provide heat during transitional periods. "
This statement is ridiculous. The entire point of a radiant heat system is so that a forced-air HVAC system - with all the messy ductwork & filters where mold and mildew will gather and grow - is completely unnecessary.
You simply have to plan ahead.
Maybe I'm overdoing it here, but I like the idea of having to pay attention to the forecast and the outside weather changes. It seems like it would help me to think about my energy use in a different way as well as bringing a consciousness of the natural world into my home. Sorry if I sound a little hippy-dippy here...
"I've heard that you can actually set the temp a bit lower than you would another heat source because warm feet tend to equal warm body. Is this true? "
Yes, it's true - and one of the reasons that a radiant system is so much more efficient and economical to run than forced air.
Sounds nice. How is it in the bedroom? Does your bed get too hot? I like every room to be about 68-70 except for the bedroom I like to be around 65 - so since you said it takes a while to heat up I'd imagine it's not as easy to turn up and down depending on when your sleeping, etc.
I had a similar experience to Stephen living in Korea for two years... radiant floors abound! And they were fabulous! I wish my parents house in chilly DC had them, where dry winter air the transition from a wet Houston winter airplane trip hot dry air being blown around the house tends to turn me into a dried out, uncomfortable mess.
We had radiant heating in the family room growing up in NY. The room was always cold, unless you were sitting on the floor with a blanket over you (which was great, but it would have been nice to sit on the sofa sometimes).
The transitional periods can be tricky. I live in central Europe now. My apartment has radiant floors. We had a cold snap that was a bit chilly due to the lack of heat. But then it warmed up. Planning ahead cannot get around the vagaries of quick weather change.
my parents have radiant heat in their bathroom. It was purely a luxury decision, not intended to replace the central heat. but in the cold Ohio winters, having those warm tiles underfoot makes all the difference!
Frank Lloyd Wright got into radiant heat via Korean (via Japan) and used it in his later houses, as did the Keck Brothers (Chicago area modernists). There are a large number of mid-century complexes in Chicago with radiant heat - some by Mies and his associated architects, Holsman, Holsman, Klekamp and Taylor.
I've heard you can set it lower too; it's slower to react when it's embedded in a slab, rather than in wood or on top of the slab (read the Eichler Network for gripes about it's function in mid-century cali houses or the Barbican message board - can't remember the name - in London, which has electric radiant in the topper slabs -w/o thermostatic controls). It can, though, be zoned for various rooms (as can conventional hydronic heat, forced air - and steam sort of) or designed to maintain a lower temperature in some rooms. It's gotten very popular in Sweden lately, powered via district systems or other (ground source heat pumps, or more common in new construction, purely off the exhaust air via a heat exchanger) sources. I think it can even be installed with existing hydronic systems if the pumps and controls are compatible (or just have electric radiant under tile or flooring - several friends have done with with success).
This is fascinating. If our house didn't have beautiful hardwood floors, I might be willing to rip it up and make radiant heat happen.
I loved the radiant heat when I lived in Korea although my dorm room at university had regular radiator heat which was noisy and overly hot. My friends' apartments and hotels with radiant heat were quiet and moderately warm, especially comfortable for sitting and sleeping on the floor (on flat cushions, futons or thick blankets).
Radiant heat for the whole house is a little less effective with western beds and sofas as you don't have contact with the floor. And for those transitioning seasons simply use electric space heaters in the room you are in while you are in it until you are ready to turn the floors on.
bepsf - Forced air backup isn't necesarily "ridiculous"! If the home is cooled with a forced air system (as ours is), a heating coil can be added to the system relatively cheaply and easily. It may rarely be used, but can come in handy during the transitional ups and downs that often occur before winter sets in "for good".
My parents had radiant heat in their home in Massachusetts, and it was great - they had it running under some tile floor as well as some wood, and it was equally effective.
The only drawback, IMO - when we were visiting for Christmas, and I accidentally left a bag of chocolate on the floor...and it turned into a puddle of chocolate.
One of the features that I love about the tiny rental I'm in are the radiant floors. It only takes a couple of hours to warm up, and it does away with the noisy, ugly-vented forced-air heating system most homes have.
We live near Munich and have radiant heat throughout the house. It's true, you have to watch the weather forecast and plan ahead. The system is rather slow and it doesn't make sense to turn it on for a day or two. But the "heat" (the water temperature is between 85 and 90F) is really wonderful. You hardly feel the warmth, you just feel the absence of cold.
I grew up with heated floors, they are magical!
You can put radiant heating under existing floors if you have an unfinished space under them (or plan on replacing your ceilings).
The house I rent has radiant heat in the bathroom. All of my friends are jealous. And my perpetually cold feet are very grateful that a family from Germany installed it before they sold the home!
here here for the Korean radiant heat system (ondol)! Although I have to say that my rooms heat up noticably within half an hour of turning my system on, and are usually fully warm to my set temperature within an hour, so it's not so very slow. My apartment has wood veneer floors, so it looks quite stylish as well. Actually, the only drawback is that because of the wood, I can't lay out my clothes on the floor to dry them - a lovely trick that's usually possible on the oiled paper or vinyl floors in most Korean apartments. It was a great way to ensure toasty warm towels and pj's, and can add a little bit of humidity to dry winter air.