We are building a house about 2800 square foot right now and the contractors I talked to,  recommend floor heating and wall heating.

One of my friends who has a house with floor heating says don't waste money on wall heating because its not worth it if you have good insulation, and rather put more loops in the infloor heating and wall heating comes with puncture risks..?


So my question is,  should I consider a combination of wall & infloor heating or just go 100% infloor heating.  My power source will be a geothermal heat pump.

Thanks and waiting for your opinions :)

the answer depends on the water temperatures you can get with and without the wall heating, which is a question only answered by a proper room by room load calculations.

if you're considering geo especially, that's critical to the success of your system.. don't skip it.

Rob is right.

Radiant floors and walls have much higher potential outputs at much lower design water temperatures. More tube (or rather the spacing thereof) is a minor factor in most residential applications.

Care design has to be considered including maximum surface temperature for sheet rock.

Is radiant infloor heating enough? Will it heat up a house in say -20 degrees Celsius (-4 Fahrenheit USA) to 23C (73-74 F)?

Are the use of radiators in addition to infloor heating needed?

Anyone have in-wall radiant heating as well? Is this practical or just a simple marketing ploy by the companies offering it to cash in some more?

Again, none of this can be answered without room by room heat load calculations. The answer is an unqualified "it depends".

If you are doing Geo and Radiant you need detailed load calcs, period. Otherwise you are jeopardizing a huge cash investment.

There are no ballparks, or rules of thumb, that are appropriate for geo radiant in residential homes. It's just too sensitive to water temps.

Okay, fair enough and thanks for the straight answer.

Now my next question is, how are these load calculations made?

ideally a qualified professional will do them for you.

there are free load calculators online you can play with, but output is only as good as input, and user experience has a big factor.

Radiant ceilings can produce 50Btuh/ sq.ft. This is about 4 times the load of the SIP home I am designing for today and twice the output of a typical sub-floor system using aluminum plates.

I use a dedicated radiant floor design program that performs the heat and cooling load analysis and helps determine such things as surface temperature, design water temperature etc.etc.

Just wanted to add a few kind words. no offence to heating professionals, but they rarely live with the actual systems they sell. I have lived now in several homes where in combination with the professionals we have built systems in existing homes. I love hydronic water heat. you can be very creative with it. the one thing i now know, the more the better. if you can put floor and wall and ceiling do it. the more pipe the better. you are better to have tonnes of mass and run lower temperatures if you wish, but trust me it is easier to open the window for a minute if you are hot, than it is to try and heat up a house in a hurry. also if you rely on only the floor, then everytime eyou put down a carpet, or furniture you lose some access to the floor heat. sure it all gets warm eventually, but i am not always convinced i like certain rugs and couches to get super heated as they are the first contact point with the heat system and will keep sucking heat until they start to transfer it at a much higher temp than you want them too. my wife likes to put those cute ikea bath mats on the bathroom floor, the ones with rubber backing. try lifting one up and feel how the temp is at the tile in that spot.

further notes. as for noise in radiant heat. be very carefull that every inch of the pipe is secure. we have a situation now where one of the supply lines in our retro fit in floor system is not secure and when there is a call for heat, or shuts off, it whips the line and smack against some surface and makes a pretty serious noise. so anytime you can imbed the pipes in concrete do it, or likewise if fastening, then invest in overkill. the pipes get softer when warm, and the valves get less precice over time causing i am told more rapid openning and closing of the valves, and bang the line snaps and makes noise. again the pros can tell you what they want but i live with it.

and some other notes. the pros will all argue with each other on right and wrong, so go with your gut, they often don't know as much as they think, similar to doctors, get multiple opinions, they will all differ, and then make your own decision without worrying about their feelings. also note choose the right thermostats. my pro told me honeywell @ wire. the next guy told wispo upnor,(which i have now purchased but not yet installed) as the honeywell is not meant for hydronic and is noisy. can you imagine being woken by the bloody thermostat announcing the room temp has fallen!

Radiant heating is good. But you should note some matters. If capillary tube is used, the water should be clean enough. Otherwise, the tube easily is clogged. Leakage is also a boring matter.

If I put radiant heat in a wall, it would only be in interior walls (to minimize heat loss).

I'm not really sure anyone's "gut" is a better gauge of thermodynamics than an experienced person, but hey, what can I say. Other than, it doesn't "all warm up eventually" if you cover your radiant with a carpet. that can, and has, in many cases rendering a functioning radiant system non functional to add thick rugs or carpeting to a room. a downside of floor heat definitely is restriction on floor coverings or at least a requirement for designing with floor coverings in mind.

Just because someone has "heating" on their truck or business doesn't mean that they are well informed: definitely true. But ask questions, and make sure the answers pass the sniff test. Separate wheat from chaff. It's worth the effort.

Jonr:

Wall heat is actually most effective on outside walls... you're raising the radiant temperature of the coldest plane in the room other than the windows. it *should* allow for lower water temps to have a larger effect on comfort. But I don't know what's really *better* there Jon, that's an interesting point.

I do know that you can crank up a wall surface temp pretty far if it's not drywall and people still find it comfortable. so maybe an inside, hotter wall is just as good or better.

Sigh. I'm going to have to add wall experimentation to the list of things we need to try out here in our shop.

2 questions for you. when you say talk about dry wall and the heat, can you explain. is it that drywall is a limiter, or must one limit the heat that you expose to the inside of a drywall wall.? not so much a question, but the element missing from many of your comments are the limiting factors which go into some of the choices. for example in my case i have a 16 foot inside wall that i can convert into an inside wall radiator. it is retro fit. the exterior walls are not an option. the floor and ceilings are not options. radiators would create obsticals to the current and future uses, they take up wall space, period. the big difference is often new build vs reno. in a reno you are often given fewer practical options. i wish that i had known about the ceiling option 3 years ago. i have 2 bedrooms which would have done nicely. i did heat one wall that has worked out nicely, however reading now the comments i wish i had used a cement backer board rather than drywall as i can see the drywall effects the heat transfer even before i get your answers from above. i was in a commercial building ( part of the vancouver winter olympics collection) and they had a vary nice looking 3 x 6 2 inch thick radiant panel that was suspended from the ceiling, looked nice and created the necessary heat. above it was the typical commercial pipes and vents etc so that it also acted as dust canopy.

Drywall has a temperature limitation, which limits how hot you can crank it up to. Radiant wall still is sensitive to furniture placement just like radiators are: in fact, I like radiators better most times because it makes that trade off obvious! but I'm coming around, radiant wall is often cheaper

Drywall is a fine heat transfer medium though its lateral transfer (spread) appears to be pretty weak, so tighter pipe on centers may be good if you really need to crank the output up.

I am thinking things like tile wall patches and such can allow for "architectural" hidden radiator options with tight on centers and hotter water. or larger "patches" for lower temps. Just daydreaming... for now...

Thats what i mean when i say you can be creative. the germans used to build kackle ovens, huge things with ceramic tile that they could store heat from the fire. it is the same concept here, you can run the pipes through anything, encase them in concrete decorate with tile and voila you have a radiator. personally i have used various radiators, including some very expensive cast versions made in france, but from a liveability stand point i am now a firm believer in not having to take up any floor spce with radiator. you can always pull the furniture out a few inches to ensure some flow, but at least you can place that desk on that wall. you always have to be overly mind full of radiators.

In my perception Radiant heating is good but in Infrared radiant heaters, we have electric and propane infrared spot heaters. Infrared radiant heaters a great for warming people and objects in the room. Infrared radiant heat is silent heat without a fan.









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Electric Heater

Wall heat is actually most effective on outside walls...

I agree that uneven radiant heat (cooler outside walls) makes for a little less comfort. Floor systems always have this and it doesn't seem to be a big factor - perhaps because the radiant heat bounces around and evens out. On the other hand, hot exterior walls means more heat loss through the wall. It would be interesting to see more research regarding the tradeoffs.

Heating a home is first about comfort. You trade money for it. Failing to address the heat load, which is found at exterior walls, is just bad engineering regardless of the heat source.