Cheap and reliable garage heat

[Joe69]

My house started out with a 1 car attached garage. The PO added a 2 car to the existing 1 car. The original bay has one heat duct from the furnace, but there's no heat in the other 2 bays. The addition is insulated and finished, but I have moisture issues when it starts to warm up in the spring. What I'd like to do is heat it to maybe 45-50 degrees, nothing crazy. I do not have access to natural gas, and my house is total electric. Any advice for a simple to install, reasonably cheap to run heater? I have nothing but 115v currently in that part of the garage.

 

[rlwhitetr3b]

Do you mean cheap to buy or cheap to run? Might want to consider both.

 

[mikegt4]

A friend of mine built a std. size 2 car garage in his back yard strictly for his car hobby. He insulated it very well and installed an electric heater (from Grainger I think) and he ran the heater to keep the temp at about 50* all winter. He told me that it added about $30/month to his electric bill (circa 10 years ago).

I don't remember the BTU output but it was something like this type of heater. Insulation was the key.
https://www.grainger.com/product/DAYTON-Electric-Unit-Heater-2YU69

 

[kelpaso1]

Wood stove if insurance will allow. You want to work for your heat or work to pay for a different heat? Take your pick

 

[Citation]

First, no ducts from the furnace should go into the garage. The problem is fumes in the garage will get circulated into the rest of the house.

Dumb, and simple would be a simple space heater or similar. That's not the most cost effective thing and at 1500 watts it will both use almost all the capacity of what ever circuit it's connected to and if run non-stop will add a few $100 to your electric bill over the winter.

A mini-split is another possibility. I put one of these in my last house for the converted attic room:
https://www.amazon.com/dp/B01DVW6G42/?tag=atomicindus08-20

This would run you around $1000. The sticker is $750 but I assume $100 to get someone to commission the system and more costs to install the wiring and disconnect. It would require a dedicated power line (either 120 or 240 depending on model). These are heat pumps so they can provide efficient heat in the winter. During the coldest months it won't work but it will in the transition times when you are concerned about condensation inside. You get the added bonus of AC if you want to work in the garage in the summer. The big upside is heat pumps are about 3x more cost effective for the heat they provide. So the winter heat bill would be lower. It probably isn't cost effective compared to simple electric heat but if AC in the summer is appealing then it's worth considering.

A thought the wall heat pump might also work but I don't think they are as efficient nor as quiet as a minisplit. However, I think they are about half the cost.

 

[Kev442]

I would start simple, a oil filled radiant heater. Start it at 600 watts and see what happens after a week. Might need to go to 900 watts and the full 1500 in arctic blasts.
The real question is are you opening the big doors all the time for the DD's?

 

[HenryAZ]

Mr. Heater propane tank top (single) burner is what I use. It works very well, even on low. On low, it will last about 40 hours on a 5 gallon barbecue type tank.

 

[jonshonda]

Sounds like electric is the only option, which is fine. I think it almost a requirement to have 220v for a good sized electric heater. Also ensuring the garage doors are well insulated and sealed is a great idea.

 

[matt_i]

In general radiant heat will be more efficient because it heats you and not the large volume of air.

Is the moisture caused by opening & closing the doors or does it migrate thru the concrete slab? The heat won't fix those. I would run ceiling fans on low instead to keep air circulating.

 

[teal95]

Minisplit will do what you want but will probably require a 220v line. Modern ones will provide heat down to very low temps (below 0 F). Figure roughly $2k minimum for the system. I did a DIY system and it was $1600 for the unit then I had to install it and wire it. I did look at getting one professionally installed but 3 places I called didn't do minisplitsd and he other can back with a bid of $8k, which I took as "we don't want to do it" as even the most expensive unit in my capacity range was less than $3k.

 

[nafterclifen]

I was in a similar situation but lucky for me, my panel is in the garage. I installed a Farenheat FUH724 (7500W) heater with a 40a breaker and 8/2 wire. On "Low", it keeps my garage 50-55 F even in the cold of winter when it's below freezing. It is so worth it!

 

[glentre]

Mini splits are nice but they are expensive to buy and install. Suggest you look into a window type heat pump or an outside wall hung Bard heat pump unit with strip heaters for the coldest months.

Glen

 

[Citation]

Having installed my mini split I don't think they are necessarily expensive to install. The cost does depend on how much you can do on your own. In my case the two expensive parts were paying someone to decommission the old system (drain the remaining freon and remove the condenser unit) and paying to have my system commissioned and adding a bit of extra freon to deal with the longer than normal lines. That was $200 total. Since the power for the old system was already there the hardest parts were installing the inside unit and running the lines. If this was a new install I could have saved half that.

If running power (120 or 240, either way you will need a dedicated circuit) isn't too hard then the rest of the install will likely be reasonable. As for cost, I would estimate $1000 vs what others have suggested but that is based on using an off brand system and self installing. No doubt other considerations could raise the price to what others are suggesting. Regardless, a mini split is one of the most expensive up front options.

 

[Bretny]

You will always have moisture issues in the spring with a cold garage and warm humid air outside. If you open the door your letting warm humid air in and its condensing on the cold things in the garage.

 

[rburke65]

Cheap would e to tap into you neighbors gas or electrical service. Reliable would be hoping he pays his utility bill.

 

[kbs2244]

I like propane for this.
A small RV style furnace (cheap to get used) will give you the heat you need with the outside combustion venting to avoid moisture problems.

 

[nadogail]

How about a Waste Oil Burning Heater?

You might even work a deal where you are doing someone a favor by taking their waste oil and its disposal problems off their hands.

Your waste oil could be stored in a IBC Tote, I see them on Craigs List; free for your doing someone the favor of hauling them away.

Waste Oil Burner plans are on the Internet.

 

[oldmxracer]

The OP said cheap and reliable and also stated He only has 115v.

Do not have a clue what He might want to spend.

Thermostatically controlled kerosene or propane fan forced heater would get it done, sell it off if when You want to upgrade.

 

[bbxlr8]

Wood stove if insurance will allow. You want to work for your heat or work to pay for a different heat? Take your pick

I use a woodstove in the house w/ unlimited access to wood and would LOVE to have one in garage/shop. But tread carefully, most insurances and codes will not allow and those that do were grandfathered or taking a risk should a fire occur.

I had a propane dual vent wall furnace in garage in my last house - brought it with me 8 years ago with great intent (still in storage) as I have not caught back up to my "old life" with well set up garage/workshop.

I am back on here for inspiration (long-term reader) & have been just getting by in the new place and want to change that. My current solution is one of those tube-type propane jobs that sounds like a jet taking off! (not ideal but takes the edge off)

 

[Prospecter]

Coastal Maine: I started with a Kerosene space heater out of necessity. Turns out that gave me an excellent handle on the BTUs I needed to heat the space. When able, I installed a Rinai propane heater, which is vented outdoors. $$ to purchase, but great heat, and lower fuel costs to heat. I only heat when I am in the shop, so costs are pretty reasonable. ($200 /year)

 

[Fibersport]

Nobody mentioned a pellet stove, a little higher maintenance than a wood stove but easier then chopping wood. You can let it run all the time and check on it daily. Most are designed for use inside the house rather than in a garage or shop, talking cosmetics now. It will take some time to get it all warmed up but once you do it will work well.

 

[BillK]

Joe,
I have a 5000 watt electric in my attached garage and it does a great job but it will require 220 volt line. Its probably not quite as cold here as where you are but it would probably work.

I would spend a little time getting the garage sealed up as good as possible. When I replaced my original 16 x 7 wooden door with a modern insulated steel one and replaced all of the weatherstripping etc it made a world of difference as to how much the heater runs.

 

[nsula_country]

First, no ducts from the furnace should go into the garage. The problem is fumes in the garage will get circulated into the rest of the house.

Dumb, and simple would be a simple space heater or similar. That's not the most cost effective thing and at 1500 watts it will both use almost all the capacity of what ever circuit it's connected to and if run non-stop will add a few $100 to your electric bill over the winter.

A mini-split is another possibility. I put one of these in my last house for the converted attic room:
https://www.amazon.com/dp/B01DVW6G42/?tag=atomicindus08-20

This would run you around $1000. The sticker is $750 but I assume $100 to get someone to commission the system and more costs to install the wiring and disconnect. It would require a dedicated power line (either 120 or 240 depending on model). These are heat pumps so they can provide efficient heat in the winter. During the coldest months it won't work but it will in the transition times when you are concerned about condensation inside. You get the added bonus of AC if you want to work in the garage in the summer. The big upside is heat pumps are about 3x more cost effective for the heat they provide. So the winter heat bill would be lower. It probably isn't cost effective compared to simple electric heat but if AC in the summer is appealing then it's worth considering.

A thought the wall heat pump might also work but I don't think they are as efficient nor as quiet as a minisplit. However, I think they are about half the cost.

Where are you finding someone to comission a DYI system for $100? Service call alone can be $100...

CT

 

[nsula_country]

My house started out with a 1 car attached garage. The PO added a 2 car to the existing 1 car. The original bay has one heat duct from the furnace, but there's no heat in the other 2 bays. The addition is insulated and finished, but I have moisture issues when it starts to warm up in the spring. What I'd like to do is heat it to maybe 45-50 degrees, nothing crazy. I do not have access to natural gas, and my house is total electric. Any advice for a simple to install, reasonably cheap to run heater? I have nothing but 115v currently in that part of the garage.

115 volt (Technically 120 volt) circuit limits you to a plug in space heater or a window unit. Electric heat needs a dedicated circuit. Circuit size depends on heat unit choice.

Most garage heaters need at least a 30-50 amp 240 volt, dedicated circuit.

Other issue is where is this "heat duct" coming from? No code allows sharing attached house/garage forced air systems.

CT

 

[Citation]

Where are you finding someone to comission a DYI system for $100? Service call alone can be $100...

CT

I posted a help wanted add on Craigslist.

 

[mrjohnsmitt]

Mr. Heater propane tank top (single) burner is what I use. It works very well, even on low. On low, it will last about 40 hours on a 5 gallon barbecue type tank.

+1 If you need a fast heat and easy installation

 

[Joe69]

The OP said cheap and reliable and also stated He only has 115v.

Do not have a clue what He might want to spend.

Thermostatically controlled kerosene or propane fan forced heater would get it done, sell it off if when You want to upgrade.

I guess I should have been a little more specific. If I need to upgrade to 230v, I will.

I'm not looking for what I would consider temporary heat, such as kerosene. I don't go in there much in the winter, I just store my classic cars and Harley in there. I really want something I can install, and just "forget about".

I'm not necessarily trying to go cheap, more like most cost effective. I'm more concerned with raising my utilities, than I am initial investment. I'm really leaning towards some sort of electric heat.

I hope that clears things up a little better.

Joe

 

[Joe69]

First, no ducts from the furnace should go into the garage. The problem is fumes in the garage will get circulated into the rest of the house.

A mini-split is another possibility. I put one of these in my last house for the converted attic room:
https://www.amazon.com/dp/B01DVW6G42/?tag=atomicindus08-20


A thought the wall heat pump might also work but I don't think they are as efficient nor as quiet as a minisplit. However, I think they are about half the cost.

I'm 99% sure that garage duct was put in when the house was built. I'm on a slab, and all of the ducts are in it. There's really little concern of fumes in there. There are no gas appliances in there, and it's been a couple of years since a car has been parked in that side of the garage.

The mini-split is just the type of idea I was looking for. I'll definitely do some research on them. Like I've stated, I don't really spend much time in this garage, I basically use it for parking only. I work out of my pole barn.

Joe

 

[WVBrady]

...The mini-split is just the type of idea I was looking for. I'll definitely do some research on them. Like I've stated, I don't really spend much time in this garage, I basically use it for parking only. I work out of my pole barn.

Joe

Be sure to check what the lowest temp it can be set at. A few have a "vacation setting".

 

[Citation]

WVB's comment had me curious. It looks like the Pioneer mini-splits noted an "away" capability and allow heat temperatures as low as 46F. That said, I think the lower outside temp limit seemed to vary quite a bit if icing of the coils was a possibility. If heat in the garage in the coldest months is an issue I would suggest some type of backup heat. In my case I used the gas furnace portion of the previous HVAC system as my backup heat even though the two systems independently controlled.

BTW, I just had a look on Amazon for generic through the wall units. They seem to run a bit over half the price of the mini-split and are about half as energy efficient
https://www.amazon.com/dp/B00QXU971Y/?tag=atomicindus08-20

This is a single sample and I don't know anything about the brand. I have no idea how long it takes to pay back $300 extra up front with 18 vs 10 SEER systems. Personally I like the idea of a smaller hole in the wall (about 3" diameter vs a window unit sized box).

 

[TheLurker]

I guess I should have been a little more specific. If I need to upgrade to 230v, I will...

Mini-split. Depending on how large the addition is. Probably a 1-1.5 ton would cover you.

You can run it so it just keeps the moisture down when it gets warm also.