heating garage

[d'addario]

hello everyone. I'm turning my attached garage into my new workout area since the room I'm using now is going to become a guest room. I live in the northeast so heating it has become an issue. I had planned on having a gas heater like the Hot Dawg put in but I have another idea that might work but I'm not sure about. My furnace is in the garage so both ducts are in the garage ceiling in plain view. My idea was to cut into both of them and put in registers. That's it. I know it won't heat the space up enough to wear a t-shirt but it will be enough to take the chill out. The garage is also insulated so that helps. My only concern is I don't know too much about how the systems are designed and I'm not sure how it will affect the rest of the house. thanks

[coolwhip]

You could have the current system zoned by a professional.

[coolguysfl]

In your description, you didn’t identify oil / gas / heat pump --

I would suggest you embrace a lic. contractor.... IF you have oil / gas heat, it requires COMBUSTION air. Failure to provide combustion air and keep flammable items a safe distance from your furnace & flue could pose a sever health & safety issue.

[drcustom]

D'addario,

Cutting new outlets into your trunk lines ("both ducts")--as you described--above the garage area presents a few issues right off the bat:

1. Not sure if your furnace is sized correctly for the house, but if it is, suddenly broadening the structure's overall heat-loss (load placed on your furnace) would definately cause diminished performance elsewhere in your home.

2. Sudden pressure drops, especially right off the furnace/blower, as a result of your new registers upstream of your living space will definately return diminished airflow performance throughout your home. If your ductwork has been sized by the book, and even if it hasn't, it was designed systemically. Unilaterally adding zones without checks and balances on the rest of the heating system, will positively result in pi*s poor performance.

3. Most importantly, though I'm not sure the scope of your planned garage rehab, if there's anyway you or any future occupants of the house after resale might go back to having a garage again, cutting return vents therein will distribute poisonous gases (CO, et. al.) throughout your entire home via the duct system if a car has been started while your furnace is cycling. Your plans wouldn't pass inspection around here unless you removed the garage door and permanantly walled it in, so as to prevent the above. However, not everyone pulls a permit...

Call a good HVAC company and they will provide lots of safe and reliable ways to do as you wish. Good luck with your project.

[classicrock4you]

and another thing.....

If you add supply registers and don't put a return there you will create a significant vacuum efect - if return sucks in 1000cfm, only 900 goes back into the house and 100 into garage, the system will try to replace the missing air by sucking unconditioned air from the doors, windows, light fixtures, switches, receptacles. Now your system works overtime, utility costs go up, and comfort takes a nosedive.

get a professional, well worth the money

[gonekuku]

I agree with all of the above replies 100%. Don't hack your ducts on your own.

If this garage is well insulated, you may be comfortable with a 1600W electric heater. It will cost you $40 to find out.

How many sq ft is the garage, height? How many ft of wall touches the outside vs. the heated house? What's above the ceiling? What's the R-value of the walls, ceiling, door? How cold is it outside?

All this can vary your heat load from 0.2 to 1.0 ton. A even a 0.5 ton tax on your furnace could create significant comfort problems in the house.

Let me know the numbers, I'll tell you a thermal load ballpark.

[totaleclipse]

Not sure what the codes are in your area, but where I live, what you are wanting to do is aganst code unless you wall up the garage door so that you can no longer drive a car in the space. A rep. lic. contractor should know what code states in your area.

[d'addario]

thanks for the replies. I figured it wasn't a good idea but I had to ask. The first thing that did occur to me was the codes since a return vent would be in a garage and even though I don't park any cars in there it still isn't a smart thing to do. The garage is 3600 cf and well insulated including insulated garage doors with attic space above it that is also insulated. 500sf of wall is exterior and a 184sf is interior. There are no windows. The floor is concrete. From what I figured out I need at least 7000 btu and one of those 1600 watt heaters might do the trick. I know they max out at around 5000 btu but I don't need it to be 70 degrees in there all day. I'd be happy with 50 for 2 hours . That's it.

[tocoolu]

Get yourself a nice Gas Unit Heater put in. If cooling is neccesary as well, i would consider a PTAC (motel type unit) or perhaps a nice Ductless Split System by Mitsubishi.

[hillbilly tech]

How many square feet is your garage,i myself have added more ductwork to systems that were working fine and had pretty good luck with it,but i am prepared to put it back like it was if the homeowners are not happy,just depends on your situation and its hard to see everything here of the computer,if every thing is easy to get to its not that big of a deal to take say and add a couple of 6 inch boots to the system and forget about the return and leave the door open to the area.But the previous post are correct with the problems you can have,but it doesnt mean you will.I just posted for i have done what your wanting to do with no problems but the other day a guy wanted this done in his house and there was no way of it happening.His system was in the basement and he turned his garage into part of the liveable area,no way would i have done that in his situation,would have been to much work to try something that your not sure is gonna work,just depends on the situation.

[zzyzzx]

I would put on sweats before doing the workout. No real need to heat it if you are dressed properly and getting a good work out.

[dan sw fl]

There are no windows. The floor is concrete. From what I figured out I need at least 7000 btu and one of those 1600 watt heaters might do the trick. I know they max out at around 5000 btu but I don't need it to be 70 degrees in there all day. I'd be happy with 50 for 2 hours. That's it.

TRY one .. if not sufficient for a reasonable heat-up period
try 2 1500 W electric heaters to heat garage to
about 30'F more than the outside temperature.

[Airmechanical]

i agree that if temp. control is needed in the garage
a seperate system would be a wise choice to
avoid air pressure and I.A.Q. issues.

I.A.Q.= indoor air quality

[TGGsucks]

Are you a Daddario? If so, you can afford to put radiant heat in the foor...Have you looked into a Rannia heater, the rep in is Franklin Mass?I don't know if you have gas? I am thinking about putting in a new 410a ductless heat pump, without an electric element in the AH.the new 410a gas does have a lower boiling point,so it will still put out heat in our area when it is very cold out.A jealous neighbor, I like Daddario's, good people and materials..Or try a wood pellet stove, like Harman free standing.....Zoning air, is a bad idea in residential.......Bad,Bad,Bad.only ham and eggers do that, cheap way of getting out of two systems...

[gsilcox]

We install Rinnai's as well as Hot Dawg's in garages all the time. It seems for your application a Rinnai would work perfect (quieter than the hot dawg):D