Heating My Garage Help!

[Nate_K1500]

Looking to heat my garage, its 24 deep by 22 wide. in floor lines are roughed in already.
Whats your thoughts? Forced air or in floor?

[ghostguy6]

Attached or separate garage? How much time do you spend in the garage? In floor takes longer to heat up and generally must be left on all winter. If your an occasional user with a workbench in the garage a forced air would be better.

[CaberTosser]

Forced air = cheapest

In floor = best. Many ways to do it ghetto, many ways to do it properly. Hope they installed insulation beneath he slab.

Being that it’s my occupation I’d always select in-floor heat. Because a garage has an overhead door be sure to run a minimum 33% glycol mix in it for that time during a cold spell that you drive away and the broom, etc falls down and bumps the door back up. Thats the day most likely for a circulator to fail (I’ve actually seen this and they no longer have floor heat in their attached triple garage)

[riden]

I've had both, I would now never go without in floor heat in a garage.

It heats so much more even and it is so much more enjoyable being out there with a warm floor. And what a difference when it comes to thawing out a vehicle.

I admit, I am a big fan.

[Trochu]

Originally Posted by CaberTosser

In floor = best.

Are you seeing moisture issues with people using in floor heat? I have two relatives with attached garages, one with radiant the other with in floor heat. As either option doesn't utilize any sort of air movement, the snow melts off the vehicle and evaporates, causing mold/mildew issues. Are guys with in floor heat putting air exchangers in their garage or what are they doing?

[CaberTosser]

Originally Posted by Trochu

Are you seeing moisture issues with people using in floor heat? I have two relatives with attached garages, one with radiant the other with in floor heat. As either option doesn't utilize any sort of air movement, the snow melts off the vehicle and evaporates, causing mold/mildew issues. Are guys with in floor heat putting air exchangers in their garage or what are they doing?

I've neither seen the mold issue nor exhaust issues to correct it, not to suggest it does not happen but it's not crossed my path personally. A garage being built would be best off having a trench drain (floor drain at minimum) and an adequately sloped floor for the snow and ice that will be melting off their vehicles. A humidistat operated HRV would be a good option as well.

[Redneck 7]

I’d go infloor heating, use a hot water tank and plumb it for water instead of glycol. Since it’s your primary home it’s not hard to make sure it doesn’t freeze. Cheaper to set up then glycol and a boiler.

[Ronji]

Forced air is faster if your working inside on the short term.
Slab heating is great for

Keep in mind, whenever you heat a garage in the winter. When you bring a car into the garage and all the snow is in the wheel wells, it will melt. Where is that water going to go, if you have no floor drain. And, what do you do with all that humidity.

We are seeing in many situations, especially in new garages that are well insulated, with proper vapor barrier, excess frost build up, as there is no place for this moisture to go. We have been forced to install de-humidifiers is some cases.
If you go with a forced air, make sure you have adequate air circulation. The moisture will never dry out in the far corners, and in some cases cause some mold issues.

We have also found that due to slopes in the pad usually going towards the overhead doors, ice is forming under the overhead door and freezing shut. This is eliminated with the slab heating, (but then the water runs out under the door, and freezes on the drive way)

Can't beat a warm garage and a warm truck at -30.

[Nate_K1500]

Should have specified it's an attached garage with a floor drain I won't spend a ton of time in there but I do like to Tinker around on occasion just trying to see will be cheaper to initially set up as well as to run all winter the forced air I would try to keep the temperature around 10 degrees Celsius the in floor I'm not sure what temperature I would run it at

[^v^Tinda wolf^v^]

I’m running a modene hot dog in my garage and I’m very happy with it. Going on year four with no issues.

[expedition]

My garage is detached 24x26 i run a 10 foot radiant really like it . Know people with attached floor heated lots of humidity issues . Even with a floor drain . Bring in a vehicle and it drips onto a hot floor you get high humidity . Cold floor not nearly the humidity.

[liar]

my last garage had in floor , this one is a radiant heater and i like the radiant better . i park two vehicles is it every night and the constant snow/ice off of the vehicles created humidity issues with the in floor . if the garage was more of a work shop in floor would be good . a vent fan with a humidistat could of controlled the humidity with the in floor heat by evacuating the damp and warm air and then i could of heated more air but i dont think that is the most economical way to go .

[liar]

another thing to consider , depending on what you use the garage for , is that changing the temperature with in floor heating takes time , a long time . radiant / forced air can warm a building up in 15 minutes . in floor heat can take hours .

[yoteblaster]

Originally Posted by liar

another thing to consider , depending on what you use the garage for , is that changing the temperature with in floor heating takes time , a long time . radiant / forced air can warm a building up in 15 minutes . in floor heat can take hours .

Precisely the reasons I went with forced air when I built a 26x28 detached garage last year

[CaberTosser]

Originally Posted by liar

another thing to consider , depending on what you use the garage for , is that changing the temperature with in floor heating takes time , a long time . radiant / forced air can warm a building up in 15 minutes . in floor heat can take hours .

Absolutely, in floor heat is for when you want to maintain a constant temperature. If you want to subject your garage/shop to wide temperature swings then select forced air or an infra-red heater.

[Xbolt7mm]

Originally Posted by Nate_K1500

Should have specified it's an attached garage with a floor drain I won't spend a ton of time in there but I do like to Tinker around on occasion just trying to see will be cheaper to initially set up as well as to run all winter the forced air I would try to keep the temperature around 10 degrees Celsius the in floor I'm not sure what temperature I would run it at

I would wonder where the floor drain drains to?

[CaberTosser]

Other factors that might be considered if you use the garage more as a shop than for parking is that the in-floor heat is dead-silent which might help if you're listening to music while woodworking or such. If you're making lots of sawdust then slab heat is far preferable as unlike unit heaters or radiant tubes it won't become dangerous when its covered/filled with sawdust. Unit heaters and infra-red tube heaters require frequent blow-downs with compressed air in order to reduce the fire hazard that such conditions would present. I used to have a truss plant client that had about 10 standard gas-fired unit heaters in their shop and their insurance company required that they have the unit heaters blown out once or twice a year. I'd be up there shutting off the units prior to cleaning them so as not to ignite the sawdust that I was blowing out of them. Those were older units with standing pilot lights so the chance of ignition was significant, there would be some significant sawdust accumulation on & in them.

[Nate_K1500]

Originally Posted by Xbolt7mm

I would wonder where the floor drain drains to?

Just to a pit under the garage.

[Nate_K1500]

Any idea what would be cheaper to run and to install? I have a gas line in the garage that would need to be tapped into and the in floor is already roughed in.

[liar]

the radiant heater was around $1500 to buy if i remember correctly . i installed it myself . in floor heating i sure would be double that . you need an engineered drawing ( i did for this county) , under slab insulation , the piping , and of course the boiler .

the under slab insulation may not be a bad idea either way . i am a firm believer that you can never have too much insulation .

[CaberTosser]

Originally Posted by Nate_K1500

Any idea what would be cheaper to run and to install? I have a gas line in the garage that would need to be tapped into and the in floor is already roughed in.

A compact unit heater would be the least expensive, I also like how little space they take compared to a radiant tube heater as I like to put up all manner of racks to store things using the ceiling.

[Sooner]

My friend bought a Princess Auto ceiling style heater when they came on sale and had it installed. Sure works slick in his insulated 20 x 20. Sounds like you need a furnace, not floor heating.

[riden]

Originally Posted by liar

another thing to consider , depending on what you use the garage for , is that changing the temperature with in floor heating takes time , a long time . radiant / forced air can warm a building up in 15 minutes . in floor heat can take hours .

I was very leery of this as first, as wifey parks inside every night once it gets a little cold. For me, it's simply not an issue. (24x20 attached garage)

I have a wood shop on wheels in my garage and often have to move a vehicle or motorcycle to work. It heats back up so fast!! Much faster than I ever expected. For me, I would call this a non issue.

That said, I turn the floor heat up higher than most, but my boiler is very efficient so I really don't notice a difference in the bill.

[Nate_K1500]

I'm leaning towards a 50,000 Btu forced flow... seems the cheapest so far.

[CaberTosser]

Originally Posted by Nate_K1500

I'm leaning towards a 50,000 Btu forced flow... seems the cheapest so far.

50K is oversized for that square footage, a 30,000 BTU will do fine.

[zewks]

I have an attached garage with a 30,000 BTU reznor unit heater. Although I have occasionally found water trapped under the overhead door I have never seen it freeze, even at -36. Heats up the garage from 5 degrees to 20 degrees in about 15 minutes. Also put an overhead fan in the garage to help with air circulation. This setup works for me...

[Okotok]

Originally Posted by riden

I was very leery of this as first, as wifey parks inside every night once it gets a little cold. For me, it's simply not an issue. (24x20 attached garage)

I have a wood shop on wheels in my garage and often have to move a vehicle or motorcycle to work. It heats back up so fast!! Much faster than I ever expected. For me, I would call this a non issue.

That said, I turn the floor heat up higher than most, but my boiler is very efficient so I really don't notice a difference in the bill.

If you're keeping a constant temperature, in floor is the best at certain things. That's why it's the preferred choice in large buildings like hangars. As said before, temperature changes take time. Open those big doors in the dead of winter, close them and it's warm again almost immediately. Overheads take a lot more time to recover the temperature in large buildings. I have a Modine Hot Dawg as well and it works great for a garage or small shop. Mine is a vented, sealed combustion unit as I do a lot of wood work and it's much safer with dusts, etc.

[sewerrat]

Another thing to think about is space, the in floor heater takes up more space. The overhead heater hangs from the ceiling and it will never be in the way.
I have a 24x 24 and installed a mr heater and it works perfectly,heats up the space pretty quick.

[CaberTosser]

Originally Posted by sewerrat

Another thing to think about is space, the in floor heater takes up more space. The overhead heater hangs from the ceiling and it will never be in the way.
I have a 24x 24 and installed a mr heater and it works perfectly,heats up the space pretty quick.

That depends entirely on whether the boiler/hydronic heat source is in the garage or in the mechanical room of the house. He noted an attached garage so he can pipe back to his mechanical room. Advantage: floor heat. Admittedly in cases of a detached garage where nobody buried an insulated supply and return line set then your point would definitely be valid.