Radiant heating questions

[kvom]

I am considering radiant heating in the slab of my new 2-story garage. As there will be an in-law apartment above the garage, does it make sense to leave the ceiling uninsulated and allow the garage air to help warm the apartment?

The apartment will have a heat pump for AC, so it can provide supplemental heating.

I could also install radiant in the floor joists. If I do that should I then insulate the ceiling?

The reason I ask is that my current garage didn't have the ceiling insulated, so that the guest room above it is quite cold in the winter (I'm having it insulated when the new garage is done and I an empty it).

 

[sneezer41]

always insulate, always



the whole point of radiant is that it only affects a short distance, so the only help it is to upstairs is not being cold, and an apartment usually want to be warmer than a garage

 

[MrCrewcab]

If the temperature setting upstairs is going to be warmer than the setting of your garage then insulate the floor, if its going to be the same then save your money.

By the way will the heatpump be able to heat the inlaw suite the entire winter?

 

[5wndwcpe]

If the temperature setting upstairs is going to be warmer than the setting of your garage then insulate the floor, if its going to be the same then save your money.

By the way will the heatpump be able to heat the inlaw suite the entire winter?

Maybe he doesn't like his in-laws.

 

[kvom]

I'm still waiting for cost estimates for the radiant.

Winters here are pretty mild, with a few nights in the 30s warming to the 40s generally. I am thinking that the garage would be heated to around 65F during the cold months. Prior to building my house I lived in a condo townhouse with about the same square feet per floor as the garage, as the heat pumps kept it quite comfortable.

No plans for any in-laws to live there -- the upstairs is mainly as an investment for eventual resale; house is on a slab, whereas most of the house in the neighborhood have basements. The extra storage space upstairs will be a plus, as will the ability to park 5-6 cards between the current and future garages.

Looking at the Zurn website, I'm thinking now that I could do radiant upstairs as well, either under the joists or else via firring strips laid on the subfloor with a hardwood laminate floor above that. Since the same hot water source would serve both the incremental cost should be reasonable.

Since I still don't have the plans from the architect, I can't get cost proposals from builders so I don't know what I want to spend on heating. Still I'm enjoying going through the learning process.

 

[e-tek]

I agree with sneezer - ALWAYS insulate!
Reason I decided against radiant heating was the time needed to change the temp when you want. Say you keep it at 50F/10C all the time and then want to go in and do some work...you'll need 16 hours to bring it up to a comfortable heat, or a supplemental heater to help.
(I also decided against a heat tube due to clearance, space taken up and that it gives DIRECT heat - on the side of your car, your head, etc. )
So for me, the cheapest option was the best - I have a "Hot Dawg" type electronic forced air heater with a programmable thermostat. I keep it at 45F/5C all the time and when I go in to work it takes a couple minutes to bring it up to comfy.
Just my 5 cents (I raised it from 2cents due to gas prices!)