Radiant heat - 1st month's cost

[kvom]

I just received my first electric bill since getting power to the new shop and turning on the radiant heat. In case anyone is interested for comparison:

Based on the past two year's power usage for the house for the same time period, the shop used 686 kWh. Under this assumption, the excess power cost was $71.46.

Slab is 25x36, 13' ceiling; thermostat set to 60F; 7500w electric water heater; well insulated. Average weather is low 40s at night, mid 50s daytime.

 

[Dragster Racer]

Was that near what you expected? To be honest, that seems a little high to me. How warm to you keep it in there? Those temps are only a little lower than what I would keep my shop. I would be afraid of what my 40X40 would cost during one of these weeks when it never gets above 0F.

 

[tdkkart]

Heh, if we had 50's during the day and 40's at night my heat would be shut off.........
Try I think it may have made 32F here yesterday, warmest it's been since before Christmas. Gonna be near -10 tonight.
My 16x30 shop space is costing a small fortune to heat, gonna make some changes this weekend we'll see if it helps.............

 

[kvom]

I didn't really know what to expect.

Because this was a startup month there was likely a lot more hot water needed to get the slab temperature up to equilibrium. Also, in past years we usually were away at Christmas for a week or 10 days, and this year we left for only 4 days.

After 15 years of an ice cold garage during the winter months I'm not going to complain.

 

[custom1]

Start up month probably has a lot to do with it. When you get a couple of months to get an average please give us an update.

I looked back through your build thread and see you don't have any insulation under or around the slab. I know you can't do anything about under, but maybe you could add some around the edge. I have read that the slab will lose most through the edge.

When you say well insulated can you give us more specifics? If it was in the build thread I missed it.

Thanks John

 

[kvom]

6" walls with bats (R19 I believe) and R30 ceiling. Garage doors are R9 or so.

In any case, winters are typically mild here and I will need the heat only 3.5-4 months per year. I'm actually more worried about the AC.

 

[Notch1988]

I'm afraid to see what my gas bill will be once I turn my heat on. Tonight it's -35, the windchill is -48.

 

[bobs409]

kvom, thanks for letting us know about this. I've been wondering what it might cost to heat a garage with electric/radiant but no one seems to share this type of info here.

I have a 28X26 garage that I am going to heat with an electric boiler/radiant tubes in floor for next year. It's colder here in Pa but I may keep it set a bit lower than 60 so that might help.

Hope you give us next months report too!


Thanks,

Bob

 

[veratyr]

I had no idea that radiant heat was that expensive... i was debating whether or not to tear up the garage floor and install that, or go natural gas. thanks for the heads up. probably be better with natural gas here then (we can see -35 during january here). i'd rather not know what the bill would be with radiant heat in that lol

and are we getting into a "its colder here than it is there" conversation? if so i'd like to contribute. I'm from minnesota, last week we had a -41 windchill, and i made a video of me running around the house and doing snow angels in my boxers at 3 am (drunk).

 

[RAYJAY]

kvom, thanks for letting us know about this. I've been wondering what it might cost to heat a garage with electric/radiant but no one seems to share this type of info here.

I have a 28X26 garage that I am going to heat with an electric boiler/radiant tubes in floor for next year. It's colder here in Pa but I may keep it set a bit lower than 60 so that might help.

Hope you give us next months report too!


Thanks,

Bob

hi bob your in PA also ? welcome to the board

Jeff

 

[Dragster Racer]

I'm staying away from the video!
I think we can throw away the first month's data. It probably did run non stop for the first couple days just to bring the slab up to temp. Let's hear about next month. IMO, I wouldn't tear up good concrete to go with in-floor. Just hand a gas tube and be done with it. Nothing wrong with in floor, but lots of expense with the tear out.

 

[Burl]

Wonder what that would equate to with natural gas? On the start-up note, how long do you wait until you turn on your system? Just how cold do you let your slab get?

 

[83trekker]

What you pay for electrciity, first month will always be huge cost, natural as will deff be cheaper.

 

[Oldram__Newram]

I got my Natural Gas bill for the first FULL month (Dec.) about 8 days ago. For the first month the shed cost me $162, for the two weeks of start-up it was a little over $125 I think. Average outside temp for the Dec. bill was 28, I kept the inside between 45 to 50, so about a 19 deg difference inside to out. It's 40x40' 14' ceiling, R19 walls, R38 ceiling, four insulated garage doors, four windows, two man doors, 1" insulation under slab with 1500 ft of 1/2" pex. I use a standard 30 gallon natural gas water heater (32,000 BTU per hr input). Januarys bill will be scary, we had a week and a half that never got above 0 outside here in Wisconsin!!

 

[Charles (in GA)]

Slab is 25x36, 13' ceiling; thermostat set to 60F; 7500w electric water heater; well insulated. Average weather is low 40s at night, mid 50s daytime.

I think you need to rethink those average temps. I'm a hundred miles south of you and its been unbearably cold here, we've had several nights in the high teens and it was colder in N. Georgia. Did you not run the heater those nights, or are you sitting on top of a hot spring?

Charles

 

[custom1]

ITbImaODekU[/media]

HA HA HA HA. Oh man that was funny. I especially liked the "Edits".

 

[kvom]

I think you need to rethink those average temps. I'm a hundred miles south of you and its been unbearably cold here, we've had several nights in the high teens and it was colder in N. Georgia. Did you not run the heater those nights, or are you sitting on top of a hot spring?

I was trying to come up with an "average" as an example to compare for people in other parts of the country. I do have it set all the time, and did so during the recent cold snap. We also had some days where the temps got into the 60s and 70s during the day, so obviously the pump doesn't run during that time.

I set the water heater thermostats to 125F, but the actual water temperature it delivers is about 118F.

 

[kuhner]

This is my second year for my radiant floor heating. The garage is 32X40 with 10' ceiling. It is a block garage and mostly under the ground on two sides and insulated with 4" white foam on the exterior exposed walls. 2" Owens Corning under the slab. The walls have about 8 yds on concrete filling them so with the blocks and the floor I have a huge thermal mass.
Last year I started it up I had electric bills of about $140 during the coldest month. It ran 70 - 80 bucks on the other "normal" winter months, runs the minimum the rest of the year $25. This year we had a very cold November, my electric was $45, December bill was $35. Our January has really been cold so it will be interesting to see how it does, will be a real test.
I am in the garage every day for at least two - three hours a day, and Saturday and Sunday all day running lights and other power equipment, welders, compressor etc.
I keep the temperature about 58-60 degrees.
I love radiant floor heat, and with my electric bills that I have been seeing this year makes me even love it more.

 

[LoneGunman]

I had no idea that radiant heat was that expensive... i was debating whether or not to tear up the garage floor and install that, or go natural gas. thanks for the heads up. probably be better with natural gas here then (we can see -35 during january here). i'd rather not know what the bill would be with radiant heat in that lol

and are we getting into a "its colder here than it is there" conversation? if so i'd like to contribute. I'm from minnesota, last week we had a -41 windchill, and i made a video of me running around the house and doing snow angels in my boxers at 3 am (drunk).

LOL, dude you have some issues.

 

[6th Gear]

I'm planning a detached 30x40' w/ loft and on the fence about radiant heat.

I'm in NE Ohio, we have propane & electric out here. We pay about $180/mo for our home electric already. Winter months are not any cheaper than summer months it seems, as cooling isn't needed much in the summer.
On the other hand... Propane isn't cheap either.

If I was going to keep the building warm constantly like most of you, radiant would make sense, but what if I was only going to use the building on a weekend during winter, or just for a few hours one 1 or 2 days a week during winter?

Trying to decide if radiant is worth the initial installation cost + monthly for my situation... thanks

 

[dropride]

How long would it take to raise the temp from say 45 to 65?

 

[boiler7904]

I had no idea that radiant heat was that expensive... i was debating whether or not to tear up the garage floor and install that, or go natural gas. thanks for the heads up. probably be better with natural gas here then (we can see -35 during january here). i'd rather not know what the bill would be with radiant heat in that lol

and are we getting into a "its colder here than it is there" conversation? if so i'd like to contribute. I'm from minnesota, last week we had a -41 windchill, and i made a video of me running around the house and doing snow angels in my boxers at 3 am (drunk).

I think the quote at 2:21 in the video pretty much sums it up.