Building a new house soon. Is it worth having a underfloor heated garage?

[vchadha]

So living in Canada we get extreme winters with temperatures as low as -40 celcius so it takes a while for the battery to warm up and this of course uses more range.

I am due to start construction of a new house and have the option to heat the garage using hydronic underfloor heating. Of course this comes at a cost approx. $7000 plus the annual energy usage. Normally I do not heat my garage at all as I just use it to park my car.

Do you think it would be an overkill to heat the garage during winter or is it just not worth it?

 

[Joules Verne]

If it's also a workshop, it may be worth it.

If it's just to park cars, I have yet to hear any of my cars complain about being parked in a cold garage.

 

[Boatguy]

Probably more effective to use the Tesla climate controls manually from the app, or to use the "Smart Preconditioning" if your schedule is pretty regular. Yes, they use a little range, but unless you departing on an extended trip it's probably not material. And if it does use significant amounts of energy, and the car is plugged in, it will top up again.

 

[tinm]

I find that my battery's 90% state of charge drops during cold winters and pops back during summers. It's already begun a gradual climb out of the "winter mode" of 226 mi @ 90% (for a 2013 Model S 85). I've often wondered if the ice-cold garage contributes to or even causes this phenomenon. During the summer months the garage will be blazing hot (it cooks in the sun all day, gets to around 90, stays in the 80s all night), and the battery seems to be very happy in those conditions.

I've often thought about radiant heat in the garage. Makes no sense to add it after the fact, but I wouldn't mind it in a future house. I might go for a heated driveway first, though..... but they cost a fortune..

 

[1208]

Just put thick insulation board, like celotex under the concrete base, it will prevent cold getting in from ground. It works really well.

 

[Boatguy]

I find that my battery's 90% state of charge drops during cold winters and pops back during summers. It's already begun a gradual climb out of the "winter mode" of 226 mi @ 90% (for a 2013 Model S 85). I've often wondered if the ice-cold garage contributes to or even causes this phenomenon. During the summer months the garage will be blazing hot (it cooks in the sun all day, gets to around 90, stays in the 80s all night), and the battery seems to be very happy in those conditions.

I've often thought about radiant heat in the garage. Makes no sense to add it after the fact, but I wouldn't mind it in a future house. I might go for a heated driveway first, though..... but they cost a fortune..

This is common to all EVs. I've had a BMW i3 for two winters and I lose about 7% of range in the winter. Preconditioning helps, but it takes more energy on an ongoing basis to heat the car and heat the battery, and that's in relatively warm northern California. After all those years of ICE cars, my mindset is still "waiting for the car to warm up", but of course that's not how it works!

 

[TaoJones]

Have you considered inductive charging in the floor? It would incur a penalty, but would be one of those gee whiz features should you ever sell the place.

 

[Evbwcaer]

If you just time the charge to end about the time you are leaving the battery will be warm with no additional energy used.

In my opinion heating a garage is a huge waste of energy.

Electric cars are a lot nicer in the winter in terms of warmth. (Heat fast, burn your butt hot seat heaters, smart preconditioning, phone app)

The only reason I would have a system like that in my garage would be for resale.

 

[William13]

Much better for you than smart preconditioning is to have the car finish charging in the morning before you drive out. This warms up both the interior and the battery giving you extra range. Also turn on the range mode in the winter or you lose range when driving the car a second, third, fourth,etc time when cold soaked. This prevents the battery from wasting energy warminging itself up. You lose acceleration potential and regen with a cold battery but are unlikely to want them anyway with snow and ice on the ground.

I personally reset the % charge and turn on the heat when I wake. This means everything is warm toasty and very little waste 30 minutes later when I leave for work.

 

[patrick40363]

Put it in. It doesn't mean you have to use it but will never be cheaper to install than when building.

 

[tga]

If it's also a workshop, it may be worth it.

My experience with radiant floor heating is it takes forever to heat the room, so you can't crank the heat 30 min before going out to the shop and expect it to be warm. If you want to maintain a warm room 24/7, that's another thing.

I have a Modine heater in my 3-car (well insulated) attached garage. It is driven off a zone on my boiler. Normally I keep the thermostat at 40F (it's lowest setting), which is only 5 degrees above the coldest temp I ever saw in the garage pre-heat (point being, it's not doing much normally). When I'm working in the garage, I crank it up to 65F. It can get the garage warm in 30-60 minutes (depending on outside temp) and maintain that no problem in the dead of winter.

 

[SW2Fiddler]

I'm this very month installing Schlüter Ditra-Heat TB - the heating wire comes in 110V and 220V flavors. Spec out tile that can be parked on, set the temp and leave it. 10 year warranty.

 

[Boatguy]

I have radiant heat in the slab of the first floor of my house and in moderate temp Northern California it raises the room temperature about 1-2F / hr. Then it retains it for a long time. Basically it's slow and expensive to heat up a big slab of concrete. I think William13's suggestion is excellent. Charge to to 80%, then to 90% in the morning and the car is warm and happy.

 

[PDFS]

I have a gas heater in my three car garage. We also work in the garage year round. We keep garage at 55 degrees and when we go out to work we crank it up to 65. It heats up in about 10 minutes. If we did not work in garage I would not heat it but it is sure nice to get in a warm car in the winter

 

[smartypnz]

I think it's a great idea - especially on those cold winter mornings when you're running around barefoot in the garage. But who does that?

 

[Plan B]

Maybe use Cadet heaters in your garage instead of the heated floor?...that would be way cheaper.

 

[thx1139]

Live in Chicago suburbs. Love the heated floor in our garage. Since it is radiant heat it holds the temperature. It has a number of other benefits besides the electric vehicle benefits. When it snows and you come home and car has snow/moisture on it the snow will melt and evaporate rather then pool in the garage. If you have living space above the garage it will help it stay warm. Previous house had our master bedroom above unheated garage and the floor was colder then floors above living space.

Also a forced air option heater in garage will lose most heat when door is opened. Radiant floor heat will hold it. It is like a porcelain smoker (big green egg) versus a metal smoker. With the concrete all warm the garage will warm back up very quickly.

 

[Camera-Cruiser]

The only negative I see is the energy suck and time to warm. So you might have to run it half the year. The one home I owned with radiant floor heat was the most comfortable and consistent that I ever experienced. Not to mention warm tile in the morning makes you forget about the electric bill.

I also like the idea of thawing out all the crud under the car too.

 

[Rockster]

Since you're building, what about some sort of geothermal HVAC system? Not only would that save considerably when heating the living spaces of your home, you could probably warm your garage to around 50F with very little additional cost.

 

[S'toon]

As for the heating the garage question, keep in mind the owner's manual states:

Temperature Limits

For better long-term performance, avoid
exposing Model S to ambient temperatures
above 140° F (60° C) or below -22° F (-30° C)
for more than 24 hours at a time.

If I build my own house, I'm definitely putting in floor radiant heating for the house and garage on the table. I'm thinking of a passive home.