attached garage heating ideas

[RPW]

A friend of mine game me his old central air unit when he upgraded. Mounted it to the ceiling (horizontal) ran the appropriate sized wire and I have heat in the garage as I need it. And for the amount of time I spend in the garage it really hasn't raised my electric bill that much. I only run it when I'm going to be in the garage for more than 30 minutes.

 

[westcliffe01]

This is the kind of furnace I was thinking of:
91,000 BTU DAYTON 80% OIL FIRED FURNACE

91kbtu/hour, will run on HHO or diesel fuel $1270 One would have to check that it was permitted in a garage. For slightly less one can get hot water heaters also oil fired which could be installed remotely and just run the hot water lines to the garage with a radiator and circulation pump tied to a thermostat.

 

[mjncad]

I'm surprised you haven't gotten the Safety Police on your case yet, so allow me to step in Code typically requires some sort of a fire-resistive barrier between an attached garage and the adjoining living space. Typically this means something like 5/8" type X drywall (taped and mudded with at least 1 coat) a 20 min rated fire door assembly and to have any penetrations sealed. A duct between these two spaces would send most inspectors into orbit for that reason. Risk of fire spread, CO, flammable fumes, etc make the duct idea very bad.

There are fire dampers available that use a link that melts at low temperatures to close the damper in a similar manner to self closing doors on a flammable liquids storage cabinet. But I suspect these dampers aren't cheap.

 

[AHNC]

Generally it is not a great idea to co-mingle the garage air and the house air, and by tying them together you will possibly create some significant negative pressures in the house, not to mention likely odor issues due to the neg press and infiltration.

I represent them, so my bias is noted, but I would recommend a Rinnai EX22 or 38 for your garage.These Rinnai's are not inexpensive but they are sealed combustion, direct vent and 95% of those I sold in 1991 are still in service. Find me a pellet stove that can say the same. Fully self contained with modulating gas valve, blower and built in stat. 82% net to the space., cool to the touch and QUIET!

I located mine in my two car garage blowing right across the door wall. Putting floor pans in that old car and having that nice warm air blowing across the floor, why it was nice enough that my wife found me taking a nap on the creeper

I just sold this house and we are moving. That garage heater uninstalls easier than it goes in and is making the move with me. At the end of the heating season, I pop the cover off and gently hit it with compressed air and a vacuum.

 

[ultrarunner]

If you have a building code, it will not allow any of the open flame options, including the pellet stove, any form of wood stove, gas logs etc.

I often wondered about this... California has some stringent codes and open flame devices are often located in residential garages.

Gas water heaters are typical as well as gas dryers... the water heaters are always on a pedestal... the gas dryers are at floor level. Both have flames and in the case of the dryer, the flame is just inches above the floor.

 

[not2old]

I often wondered about this... California has some stringent codes and open flame devices are often located in residential garages.

Gas water heaters are typical as well as gas dryers... the water heaters are always on a pedestal... the gas dryers are at floor level. Both have flames and in the case of the dryer, the flame is just inches above the floor.

Well British Columbia can be just as confusing. I built a new house in 1996 where the boiler room door opened into the garage. I was required to put the gas water heater on a pedestal, but the gas boiler right beside it was allowed to be on the floor. Both were the same distance from the doorway. No wonder I hate government.

 

[ctgoldwing]

Keep in mind any air that you direct from your existing system to your garage will be made up with infiltration air to the house from outdoors. A dedicated system will ultimately be less costly. A water to coil type solution will also need freeze protection or remain active all the time to prevent damage in the garage.

If you don't mind trial and error either system you discussed will work.

I guess I'll throw my $.02 in also.

I heat my garage with a hot water unit heater (Modine brand). Its nothing much more than a heat exchanger that has a blower behind it. I do not antifreeze the system but agree you should consider that posibility. The unit is oversized for the actual heat loss of the garage (the heat loss is about 20mbh, the unit about 60mbh).

I keep the temperature at 45 degrees - it hardly runs. BUT when I want to do work in the garage I turn up the thermostat to 58 and in 15-20 minutes its comfy to work in.

All that said if I had natural gas available and were to do it again I would find a new 'scratch & dent' 90% + gas furnace that vents with pvc pipe and heat it that way. I work for a wholesale distributor of hvac equipment and we ALWAYS have dented units we are trying to get rid of. A 100mbh input furnace that is dented we would probably sell for $400-$500. If it really got a lot of jacket damage just a couple hundred dollars.

 

[wvpolekat]

If you have a building code, it will not allow any of the open flame options, including the pellet stove, any form of wood stove, gas logs etc. The units which will be allowed have to bring in the combustion air from outside, vent back outside and not have the flame exposed in any way. If it is advertised for use in a garage (as compared to a "shop") it should be permitted.

This has LOTS of assumptions. Building codes are not the same everywhere. "any form of wood stove" is not "open flame" any more than a natural gas furnace is. I have a wood burning furnace in my basement that is not open flame. I know some pellet stoves are the same as well. In my county, most building codes don't apply to homeowners doing their own work either.

The better answer is to check with local building codes as well as your insurance policy/agent. Mine only checked clearances on my stove, didn't even raise my premium.

 

[westcliffe01]

If you need a permit for work on HVAC or plumbing, there is an inspector involved. This probably applies to 90% of the population. If there is an inspector involved, its best to talk to him before making any decisions. I just know that garages specifically, due to the expected several gallons of gasoline in the cars stored there can be very sticky. If it is a shop or something else not specifically earmarked for parking vehicles and gas tanks, things can be more relaxed.

In the end it comes down to whether you have a mortgage and mortgage insurance. Insurance companies have been known not to pay if you did something that violated their coverage.

This has LOTS of assumptions. Building codes are not the same everywhere. "any form of wood stove" is not "open flame" any more than a natural gas furnace is. I have a wood burning furnace in my basement that is not open flame. I know some pellet stoves are the same as well. In my county, most building codes don't apply to homeowners doing their own work either.

The better answer is to check with local building codes as well as your insurance policy/agent. Mine only checked clearances on my stove, didn't even raise my premium.

 

[dstig1]

In my county, most building codes don't apply to homeowners doing their own work either.

That's unusual. Typically building codes apply to the resulting structure/installation, not the person doing the work. The homeowner exception is typically that the HO does not need to be licensed to do various work, but the work still must meet code.

 

[wvpolekat]

That's unusual. Typically building codes apply to the resulting structure/installation, not the person doing the work. The homeowner exception is typically that the HO does not need to be licensed to do various work, but the work still must meet code.

There are lots of loopholes like that here. I assume it is because so much of the population lives in sub standard housing that they built as they could. There simply isn't money for enforcement, nor would/could many people here pay the fine if there was one.

You would also never expect to have anyone to call the building inspector if they saw you building something and didn't have a permit or whatever. Very much a live and let live attitude.

I have seen rental properties here that were little more than a shed. Wood stove, no insulation, plywood walls between the rooms. You get the picture. Most places, that would be condemned. Nobody bats an eye here.

Heck, I still know people who don't have electricity or running water. Friend of mine that has never had electricity was visiting with his 5 year old son one day. His son had to go to the restroom. He walked in closed the door, did his thing, all while never even thinking to flip the light on. He was used to functioning in the dark.

 

[ultrarunner]

There are lots of loopholes like that here. I assume it is because so much of the population lives in sub standard housing that they built as they could. There simply isn't money for enforcement, nor would/could many people here pay the fine if there was one.

You would also never expect to have anyone to call the building inspector if they saw you building something and didn't have a permit or whatever. Very much a live and let live attitude.

I have seen rental properties here that were little more than a shed. Wood stove, no insulation, plywood walls between the rooms. You get the picture. Most places, that would be condemned. Nobody bats an eye here.

Heck, I still know people who don't have electricity or running water. Friend of mine that has never had electricity was visiting with his 5 year old son one day. His son had to go to the restroom. He walked in closed the door, did his thing, all while never even thinking to flip the light on. He was used to functioning in the dark.

Makes me yearn for the simpler life...

Living in the city, I've had people call when they say Mom landscaping with a shovel and wheel barrow or when my neighbor was having new double pane windows installed...

It wasn't always like this... with the influx of people comes additional layers of regulation...

I've worked in areas where the owner had a free hand in building... the only caveat was the tax assessor would come out and measure when the building footprint or height changed.

Heck... we have 70 roving inspectors whose job it is to write citation if they witness fireplace smoke...

The only thing that matters is what is permissible for a given location and time...

 

[WM75Guy]

In a previous life I was a building inspector. Texas law allows a home owner to do work on their homestead exempt from licensing requirements. In unincorporated areas there are no codes. Most cities have code requirements for permits and inspections for homeowner work with reduced fees. If you ever sell your house and the mortgage company or new owner gets an inspection you need to be able to prove the work met code and was inspected. I saw many a sale go down in flames because of homeowner work that was not up to code, like running 110 volt fixtures with 18v low voltage landscape wire, penetrating the garage firewall to add a room, and plumbing that was not vented.

 

[bironacad]

I am looking at heating my work area and garage. My cousin is using the propane unit heater found in the link below for his garage. It is a through wall vent design and is up off the floor avoiding low lying fumes, it also has an option for sealed combustion (air for combustion comes in from outside and then these combustion products are vented outside). He said that the base of the unit heater had to be 8' off the ground by code. I am leaning toward radiant heat same idea it is up off the floor but has the advantage of not being affect by an outside door opening, you often see them on loading docks and community centre ice rinks. As an old HVAC guy no longer in the trade (my cousin is as well) there are building and fuel codes to follow which do not allow for mingling of the garage environment with the household environment, for reasons obvious and already stated, in actual fact there is a part of our building code that does not allow for different rental apartments to share the same forced air from one unit to another. Horizontal Oil fired units had to be a minimum height above the garage floor, at one time they were very common, some able to burn waste oil. I would have to check the code book but they were always at least 7' to their bottom above the floor in the garage.
Electric heaters require no combustion air so this is a plus but the cost is prohibitive to run. Anything that burns fuel requires air for combustion so units that bring in air for their combustion will eliminate negative pressure in the working environment which could result in carbon monoxide poisoning. There are reasons why consulting with building inspectors and licensed people are recommended. A lot of people in the area of my property are using outside boilers that are wood or pellet burning so all combustion happens outside, the hot water can be piped to multiple areas and gives the added advantage of zoning the heat. The heat to the house or garage is thereby radiant water. Most commercial garages are using some form of radiant heat, water or sealed combustion. There was an earlier link to a supplier of radiant heaters. My two cents. My cousin purchased his propane unit heater at TSC here are some links:

TSC Stores
TSC Stores

 

[grsthegreat]

again i agree with the comment about the safety police..... a fireplace on the ground would allow combustion source too low to the ground. you could place the fireplace 24" above the ground and probably be safe (but id still be afraid due to the gas vapors from vehicles, lawnmowers, etc...) but kinda hard to load wood, etc. if you penetrate the garage wall with any duct work, you could allow a path for a fire to follow into the main structure. I have been in the building trade for over 30 years, and have never been able to DUCT a garage from a home system either directly or indirectly. they will allow a liquid filled tube embedded in the slab to operate on a house system only. Personally what i usually see are 5000 watt electric heaters used where people want to keep a constant temp of 40 deg or so thru winter. if you only want to heat it up while your in there....use a ceiling mounted nat gas/propane heater. i have a 125,000 btu furnace in my 30 x 40 shop. i only fire it up for 15 minutes to take the temp up to where i can work in shirt sleevs in the dead of winter. i couldn't afford to leave it on....but i dont need to. I do alot of work out there in the winter with my metal projects (have a CNC plasma table and do metal art/work). for a standard 2 car garage, a 50,000 btu would heat you out in 10 minutes of use. as long as the room is insulated. But this is only my opinion....for what its worth.

 

[bironacad]

again i agree with the comment about the safety police..... a fireplace on the ground would allow combustion source too low to the ground. I do alot of work out there in the winter with my metal projects (have a CNC plasma table and do metal art/work). for a standard 2 car garage, a 50,000 btu would heat you out in 10 minutes of use. as long as the room is insulated. But this is only my opinion....for what its worth.

Plasma cutter me likes that

Heres that TSC UNIT HEATER:
Regular Price: $649.99HEATER BIG MAXX 45000 BTU LP
SKU # 215043
Vendor Part # MHU45LP
Brand: ENERCO MR HEATER CORP

 

[JMynes]

If you have gas just run a line to the garage, put a forced air modine type gas heater in and call it good. That is what I had in my shop in Anchorage years ago and it worked superbly.

+1! Heat the garage only when you want it warm. And it's on sale right now! Mr. Heater Natural Gas Garage Heater — 75,000 BTU, Model# MHU75NG | Natural Gas Heaters | Northern Tool + Equipment
When you figure the time, hassle, and materials to run a ductwork loop through your garage, this is a lot easier. I also doubt the ductwork loop would transfer enough heat to make much difference.

 

[Jay4200]

HVAC trained tractor guys please weigh in on my idea.

Bad all around - way overly complex. If you had FHW heat, running a loop into the garage with a radiator/blower would be the way to go. However, with FHA, you're mixing the garage and house air, which is a no-no.

Your best bet - an I am planning to do this myself - is to find a used or scratch/dent propane FHA furnace for cheap or free. You'll have to install an adequate exhaust - real easy if you find a condensing furnace. Set up the furnace in a corner and hook it to a 30gal bottle. No duct work needed - just fire it up when you are going to do work.

JayC

 

[wrath]

I did something similar once. It was an air-to-water feeding a water-to-air system. It consisted of two radiators out of 73-80 GM Fullsize trucks, 1" CPVC, two box fans, and an el-cheapo electric water pump.

It worked. However, it would take bloody forever to recover from an open garage door. The deltas just weren't large enough.

 

[Jeff H]

Hello Mr Wrath.
Thank you! I believe only you and CurlyDave on page one understood what I wanted to experiment with, either air-air or air-liquid-air transfer.

I never advocated tying into the house system in any way, and said in my post I did not want to commingle the air, yet many well meaning folks went on to warn me against doing it.

If I can find some suitable radiators I may give it a try.

Thanks