Heating garage

Looking for some of the great non-fishing knowledge that IDO can provide. Sometime this summer I would like to finish our garage and heat it. When we purchased the house 2.5 years ago, I think the previous owners were in the process of finishing it. All of the walls are insulated, about half of the walls have been mud/tapped and the other half just got sheetrock on them. The ceiling is open through the rafters up to the roof. I love the ease and convenience of storing things in the rafters, but we will put up a ceiling and insulate it. Get new garage doors as well.

The garage is 30′ x 32′, attached to the house. The house is heated by propane.

My question is what is the best, cheapest, most convenient heat source to keep the garage roughly around 40-45 degrees in the winter? When talking cheapest, I more so mean long term costs associated with it rather than just short term initial cost. I’d also like to be able to heat up to 60 or so when I know I’d be out there for a few hours. Another thing to keep in mind is that our garage does house both of our vehicles, so in general each garage door is going to open at least once in the morning and once in the evening, losing most of the heat.

Which is most appealing? Best, cheapest, or most convenient?

I have two electric heaters w/ fans mounted on my ceiling. The only thing cheap about them was purchase price.

Mookie Blaylock wrote:

Which is most appealing? Best, cheapest, or most convenient?

I have two electric heaters w/ fans mounted on my ceiling. The only thing cheap about them was purchase price.

Can’t have it all… I would say the most important thing I’d like to consider is monthly costs in relation to the upfront cost. I take it electric heaters may be cheaper up front but more costly on the electric bill than other options?

mnrabbit wrote:

All of the walls are insulated, about half of the walls have been mud/tapped and the other half just got sheetrock on them.

Make sure there is insulation behind the rock with Vapor Barrier. Common for some builders to insulate and fire rock the common walls and just toss rock up over uninsulated walls to make them look pretty

The ceiling is open through the rafters up to the roof. I love the ease and convenience of storing things in the rafters, but we will put up a ceiling and insulate it.
Keep it open if you like it. Spray foam the roof deck and keep the open trusses. Nothing wrong with that.

The garage is 30′ x 32′, attached to the house. The house is heated by propane.
Extend propane line to the heat source of the garage. Regardless if you put in a hot dawg or standard furnace, you will need the propane orifices.

Another thing to keep in mind is that our garage does house both of our vehicles, so in general each garage door is going to open at least once in the morning and once in the evening,

losing most of the heat.

You don’t lose “most of the heat”. Most of the heat is in the objects within the garage. They are at ambient temperature. Think of it as rocks around a camp fire. Once the rocks are warm, they radiate heat until they cool. Same affect in the garage. As the air exchange happens, the heat for objects in your garage help increase the heat. Your heat source is just heating up thge ldifference in the air temp from the exchange. Just like when you park a car that is 10 degrees in there, you will feel the cold of the car until the metal warms up.

We set up separate furnaces or Hot Dawgs for that size of garage. If you have the room to spare, the furnace is awesome. If space is of concern, go with a 75 Hot Dawg

I’d look at a direct-vent, thru the sidewall unit like this

https://www.menards.com/main/heating-cooling/gas-kerosene-heaters/vented-shop-heaters/beacon-morris-45-000-btu-natural-gas-garage-heater/p-1444424894441-c-6865.htm?tid=-7693844774090281676&ipos=5

I’m selling the house that had this in the garage, I miss it already,,,,,

HRG

Attachments:

1. 

   IMG_0116.jpg
   

This is on my shortlist of projects also. I’m curious what others have to say.

I agree with the Hot Dawg, works great to keep it at the temp you want. I would also suggest an air exchanger. I have built 2 heated garages. The first time no air exchanger and we had lots of ice/water build up on windows, doors and the base of block around the floor. Total pain when it mixed with dust/dirt.

Garage #2 has an air exchanger. Huge difference. Of course, not the cost effective thing to do, but much better on the windows and doors. way less sloppy.

I have a smaller garage that is fully insulated. 22×24 and heat it with a ceiling mount electric heater. I paid 100.00 for the heater from Northern Tool that was on sale and had some cost into wiring it. I had to run a separate romex line in from my panel in the house. I did have a propane heater but was old and needed more work than I wanted to get into. The heater works great. It cost me about 40.00 per month on average but well worth it to me. If I kept it at 40 degrees it may be a little less but usually will turn the heat up around 50 degrees if I plan to work in there for the evening and do this 6-8 nights a month.

I would assume you might double that cost with a 30×32 garage.

One issue that no one told me about was how bad it dries the air out. This is a bigger downfall to me than the cost. When I plan to work out there I will toss a light layer of snow across the floor just to get some moisture in the air and it helps. Just one warning anyways. It dries the air out much more than the propane heat in my opinion.

I would just get a hotdog heater that runs with Propane and a couple of ceiling fans to circulate the air. I have a 80,000 btu in my garage now which heats it up in no time.

Your floor of your garage is going to be cold so the snow\slop may not be completely dry but the ceiling fans will help.

If your ceiling is not as high to allow for that I used to have a blower that I ran with a timer that came on for 20 mins and off for 40.

Right now, I also have infloor heat in my garage slab which serves another purpose other then heat due to some soil\foundation issues I had resolved. But I keep the floor when it is sub 10 degrees at 55deg and the garage heater at 50. When it gets to above 20, I will keep the keep both at 50 deg. If it gets super cold like the -20 stuff for more then a couple of days, I put the infloor at 60 for a day or 2.

There are no building/energy codes for garages but you want to make sure that heating your garage doesn’t cause any problems with your home.

As most people have stated, an overhead forced air gas heater is best,(don’t be afraid of a little over sizing) Insulate well with a vapor barrier on the warm side. I wouldn’t install a vapor barrier on any common wall with the house that is already insulated. Ventilation is important and if not done properly could add problems to your home. Soffit venting (60 %) and roof venting (40 %) with air chutes. Depending on your truss heel height a solid wind wash should be installed. Seal all bypasses.

The air exchanger is high end bell and whistle. I think you could help the condensation issue with a $10 box fan and sweep out snow/water daily.

Nothing like a heated garage.

My garage Hot Dawg is 19 years old. Flawless. I keep it at 48 in the winter. If I want to work in the garage I can blow it up to hot in no time. On snowy winters melt water is a constant battle since we have no floor drain. I am constantly sweeping it out and chipping the ice ring under the door. Small price to pay for pre-heated vehicles. I cant imagine not having a heated garage now.

I like that I keep seeing the Hot Dawg Heater pop up by a lot of you! I was hoping not to see 15 different answers from 15 different people. I will do a little bit of research into that and see how it will work for me.

I’m going to wait until after the winter to do the project, but I’d like to do it right and get it all researched and drawn up ahead of time, including storage, shelving, etc. I hope this doesn’t happen, but baby #2 is also coming any day now, so I could see myself getting to next summer and saying “ahh I’ll do it in 2019…then 2020”

I also have a hot dawg in my insulated garage, I keep it set at 50. Only takes a few minutes to have it up to 65+ if I’m going to be working in there.

Rabbit – People may be referring to their “unit heater” (generic name) as a hot dawg (brand name).

IE. Grab the frabill.

Eelpoutguy wrote:

Rabbit – People may be referring to their “unit heater” (generic name) as a hot dawg (brand name).

IE. Grab the frabill.

Makes sense, thanks for the clarification!

Eelpoutguy wrote:

Rabbit – People may be referring to their “unit heater” (generic name) as a hot dawg (brand name).

IE. Grab the frabill.

I was being very specific to BRAND NAME – not generic. Last thing I ever want is a warranty call. Best to install quality from day 1 and not have to worry about it. Typical size we put in is usually 75K BTU
Only 2 brands we install
1. Modine Hot Dawg
2. Reznor

Randy Wieland wrote:

<div class=”d4p-bbt-quote-title”>eelpoutguy wrote:</div>
Rabbit – People may be referring to their “unit heater” (generic name) as a hot dawg (brand name).

IE. Grab the frabill.

I was being very specific to BRAND NAME – not generic. Last thing I ever want is a warranty call. Best to install quality from day 1 and not have to worry about it. Typical size we put in is usually 75K BTU
Only 2 brands we install
1. Modine Hot Dawg
2. Reznor

Have run a Reznor in my garage for 10 years now. Flawless. I’m sure the other brand is good too. Initially I tried a ventless heater, big mistake, huge condensation issues. Like Suzuki, can’t imagine not having a heated garage, it is so worth it.

ET

Another vote for the Modine Hot Dawg. My garage is roughly the same size as your rabbit but is not connected to the house. After years of running a torpedo type heater every time I wanted to work in the garage I had Hot Dawg installed in the fall of 2016. Mine runs on propane but I am thinking of switching it to natural gas if running a supply line to the garage isn’t too costly. As is, I have zero regrets.

I have a hot dawg at the cabin and had a mr. Heater at my last house. Both are great and no issues in the last 15 years. Mr. Heater was about $200 less.

Not alot to go wrong on these units, no matter what brand.
I’ve been running 4 cayenne’s for 17 years and no issues.

And I stated “may”

Randy Wieland wrote:

The ceiling is open through the rafters up to the roof. I love the ease and convenience of storing things in the rafters, but we will put up a ceiling and insulate it.
Keep it open if you like it. Spray foam the roof deck and keep the open trusses. Nothing wrong with that

I am finding some conflicting reports online, but how does ventilation work if you spray foam the roof deck? Is ventilation needed? I’ve found some things saying ventilation is always needed, and others saying that ventilation is not needed when spraying a roof deck because the spraying is going to reduce the high heat temps and eliminate the need for venting.

And as much as I like it open and having the ability to throw whatever I want up there for storage, I think I am going to probably close it just so I am paying for less area to heat up. I will probably add some sort of attic ladder so I can turn the area into storage for those things you only need once a year (wife’s Christmas decoration totes, etc.)

Does a heated garage mean lots if mice?

DaveB wrote:

Does a heated garage mean lots if mice?

Hopefully not but maybe. We already get a couple mice a month in our basement or garage. After a fresh snow, it’s amazing how many mice tracks I see in the yard. I do however think that our new garage doors and eliminating a few tiny gaps under them should seal off the garage pretty good then!

mnrabbit wrote:

<div class=”d4p-bbt-quote-title”>Randy Wieland wrote:</div>
The ceiling is open through the rafters up to the roof. I love the ease and convenience of storing things in the rafters, but we will put up a ceiling and insulate it.
Keep it open if you like it. Spray foam the roof deck and keep the open trusses. Nothing wrong with that

I am finding some conflicting reports online, but how does ventilation work if you spray foam the roof deck? Is ventilation needed? I’ve found some things saying ventilation is always needed, and others saying that ventilation is not needed when spraying a roof deck because the spraying is going to reduce the high heat temps and eliminate the need for venting.

And as much as I like it open and having the ability to throw whatever I want up there for storage, I think I am going to probably close it just so I am paying for less area to heat up. I will probably add some sort of attic ladder so I can turn the area into storage for those things you only need once a year (wife’s Christmas decoration totes, etc.)

Foam gives you great air seal in addition to R-value. The key is having it done correctly. At some point, you reach the dew point or condensation point. Having too little foam is where you run into most problems. Home owners and crappy contractors cheat the values and spray it thin. In extreme cases, it can condensate on the surface, which you never want. The beauty of foam is to have the dew point within the foam, where no air can permeate. That prevents the ability to mold.

Sounds like your set on rocking/insulating the ceiling, so that will work fine. Just make sure if you are making storage area out of standard load trusses, your re reinforcing them accordingly. Standard dead load on the bottom cord of trusses is not designed for heavy loads. In most cases, bottom cords are between 10 to 20#/sqft dead load.

Eelpoutguy wrote:

Rabbit – People may be referring to their “unit heater” (generic name) as a hot dawg (brand name).

IE. Grab the frabill.

My unit heater IS a Modine Hot Dawg. I’ve never heard anyone call a garage heater a Hot Dawg if it wasnt.

Rabbit –
Depends on the construction of your roof and how it attaches to your home. If you spray foam the underside of the roof deck, you need to make sure you insulate and seal any common areas to your home and home attic area. Some situations are easy, some are quite complicated. If all these are not sealed properly, you could potentially have ice dam issues, rot, etc.

Please note: Common trusses are not designed for storage.

Dave,
Mice do like heated garages. I use mouse bait and that seems to work well.

I have in-floor heat in my garage. Water heater in the basement full of alcohol and closed loop system running through the floor. Much like a hockey rink in reverse. I keep it set at 52 and it costs me about $75 a month. Floor drains to remove the melted slush. Of course, it was done when the floor was poured, so probably not very cost efficient with an existing floor. Sure is nice though.

I installed a Beacon Morris a year or two ago and have been happy with it in my 850 sq ft, 3 stall attached garage. I insulated and rocked the walls and ceiling. Walls are 2×6 walls, and ceiling is 11′ and is insulated at at R38. I sealed all cracks in the walls prior to insulating.

I would recommend you size the heater properly. I am not sure you would need a 75k heater for a 960 sq ft garage. I installed a 45k and it is more than enough for my garage. I keep my garage at 50* all winter, and have no problems getting it warmer if need be. I ran an extra line from my basement to the garage for the heater so I could utilize our main propane tank.

BTW, I would also strongly recommend installing 2 ceiling fans (I did one over each bay). This makes a big difference in my garage. My run 100% of the time all winter long at a low speed. I also had floor drains installed when we were building the house.

I use fresh cab in my garage for the mice.
One at each side of the garage door and one in each back corner.

The ceiling is open through the rafters up to the roof. I love the ease and convenience of storing things in the rafters, but we will put up a ceiling and insulate it.
Keep it open if you like it. Spray foam the roof deck and keep the open trusses. Nothing wrong with that.

This is incorrect. Do not spray foam directly to the roof. Ventilation is needed to keep it cool underneath the roof. Ice dams are a major concern if you heat the entire space. I have a friend who used the spray foam directly to the sheathing and he fought ice dams every year since.
The proper way to insulate is to apply vapor barrier, then rock the lid. Next install baffles to allow air to circulate from the soffits and out the roof vents.
If you want to store above, I recommend an attic ladder and using roll insulation to prevent the fibers from moving around.
Another big thing I did was purchasing the garage doors with the highest R value available. This makes my heater run very little to keep the garage at 50 degrees most of the winter.