Getting ready pour a slab for my 24' x 40' garage build. I've been thinking about putting radiant heat in the slab. Would this be a good way to heat a garage he in upstate NY?  Is this something I can do myself? I'm not talking about the boiler system just running the pex tubing in the slab.

Are you going to insulate under the slab with at least 2 inches of rigid foam?  

You'll probably find its a lot cheaper to install a regular vented natural gas or propane furnace.  The heated concrete sure is nice but it comes at a steep price.  If you're going to insulate under the slab but won't be installing the complete system right now, it won't cost much to install the PEX in the slab for a future install if you wanted to.  Make sure you use the correct oxygen barrier PEX for hydronic heating systems.

I'm not sure I want radiant heat, but putting the tubing in the slab in case I do go that route makes sence. Curious, what is so expensive with radiant heat? After the tubes are run you just to zone it and get a boiler, right?

If you are going to park salty wet cars  in your garage in the winter, the rust you are going to get will be spectacular to the extreme.

I should have at least put the plumbing in for the radiant heat but my issue is I am not in my shop all the time. I figured I would waste a lot of energy keeping the slab warm for when I might be out there!   Usually only out there on Saturday and Sundays and not for all day working.  It is easier for me to hit the switch on my propane heater and have my shop warm in 20 minutes minus the floor.


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Because its heated, or will it rust due to radiant heat?

I think the theory is keep the car frozen and the salt won't affect it as badly as a car that comes in frozen and then thaws out in the warm garage. But, if you routinely warm your garage to work on things, it really doesn't matter what the heat source is, it's still going to melt the ice.

Either way, any vehicle you drive on salty roads is gonna get lots of rust. No way around that.

Do a Google search for heated floor materials costs. Everything together is pricey. The rolls of pex are pretty cheap.

Salt and water cause more metal oxidation as temps rise. At 0-20F there isn't much happening, as temps rise, oxidation rapidly increases, heated garages make one hell of a mess on wet salty cars.

Alternatively, cold garages are hell on the people working in them!

I have a 30 x 45 shop and i just use a woodburner with 2 built in blowers that just blows into the air no ducts. I can get heat blowing in about 30 minutes from nothing and 70 degrees evenly because of the blowers in a few hours even if it's 10 degrees out.

Radiant floor heat would be pretty awesome but seems wasteful and expensive if you aren't in the shop daily. I only heat mine on the weekends when I'm home.

Thanks for the replies fellas. Been googling heat and salty cars. Never thought about salty cars rusting more in a heated garage. I think most of the time the cars will be parked outside. Wife may put her car in when it snows. I have some machine shop type machines I plan on putting in there thats the reason for heat in the garage. I plan on keeping the temp down to 45 - 50 degrees when I'm not working out there. Probably will put in a 2 post lift in a year or 2.

How often do you work in there and for how long? You need a boiler to heat it, not a residential water heater. You can run an electric or gas powered boiler only when you'll be working out there. It will take a few hours to come up to temp, but laying on your back on a nice warm slab sounds like a dream for doing car work in the winter. My brother worked in Wyoming as an auto mechanic and his shop used natural gas radiant (IR) heaters, he said they worked pretty damn well.

I know a guy who has it in a 1 car walled off from the rest of his garage. He parks his viper in there. For a work garage i would just do something you can turn on when needed

Oh yeah, 150K BTU Salamander for when I have to. Rubber mats so I don't have to be right on the concrete.

I have a 42'x60'x14' garage that has had radiant in-floor heat since 2005.
I used Radiantec for all of my parts.
The heat source is a Munchkin Boiler.  I could have used a water heater and saved some money, but the Munchkin has been fantastic and is frugal with the propane.
The temperature is kept at 49 degrees, and I will use about 300 gallons of propane per heating season.
I haven't checked, but some digital thermostats might allow you to go lower than 49 degrees and allow you to save more on fuel.
The walls are insulated with 6" fiberglass, and the ceiling is insulated with 6" fiberglass with 3/4" styrofoam over top of the fiberglass.  In the future I will be installing the 3/4" styrofoam on the walls as well.
The perimeter of the slab is insulated with 2" of styrofoam.
All of the work was performed by me, with the technical details taken care of by Radiantec.  It was a pleasure working with them.
Installing the tubing was easy, and I made a template for where my lift was going so that the tubes would not be in danger of punctures from the anchors.
While a forced hot air furnace with a plenum on top would have been cheaper, it would not have been nearly as efficient as the radiant in-floor heat.

When the wind is blowing at 20 mph and it's in the twenties outside, 49 feels like a heatwave.  

I used to use a 60k torpedo heater running on either diesel or kerosene. Used it for many years. Used to think it was great compared to the days of working on vehicles in a drafty barn and outside in cold weather.

Now that I have a vented propane heater, I'll never go back to vent free. The vented heater is nice and warm and most importantly....dry heat. No more moisture condensing on my tools! Love it!

I checked the new digital thermostat that I installed last season, and it will go down to at least 45 degrees, so there's more energy savings.
The original analog thermostat would only go to 49 degrees.

Not to burst your bubble, but check with your local zoning office first...  Quite a few states have adopted the International Energy Conservation Code and may require a "blow test" for heated spaces, as such with an actual garage door, you are unlikely to get approval from my understanding.

Hmmm never heard of that. I'll check in to it. Thanks