I am planning a 600 squaire foot mother in-law addition to a 3200 sq foot house buit in 1994. The new addition will be on the ground floor behind the existing garage and will contain one large 18 x 18 room, a bathroom, and a laundry room. The exisitng house is energy efficent and heated with a 115,000 BTU gas forced air furnace with the furnace located in the garage. I would like to zone heat the new space so I can lower the temperature when it is not used for long periods of time. I do not want to use a free standing or direct vent system since there is a question of dementia. I am not a fan of baseboard electric heat. A speparate furnace located in the garage for the mother in-law addition would seem ideal, however I am not aware of any gas furnaces that have small enough BTU ratings for such a small space. Zoning a 3200 sq foot house with a 600 sq foot mother in law space creates system balance problems. Any suggestions?
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I don't know if this is considered direct vent or not, but a Monitor or Toyo type heater would be perfect for that.
The smallest standard furnace is a 50,000 btuh input, at 80%, 40mbh out, about 5 times what you need. You could use it to heat the garage as well...
"Zoning a 3200 sq foot house with a 600 sq foot mother in law space creates system balance problems. Any suggestions?"
Residential system are seldom balanced, in the true sense of balancing. You could, if access permits, probably serve the space withthe existing system and close (fully or partially) the registers when not in use. I have a few spare bedrooms that get little air when not in use, not a problem.
Sounds like a good calculation except for the "colder than a mother-in-law's kiss" factor
O.K. fess up guys.
I can't be the only one who's first thought was:
Turn off the heat altogether and she won't stay so danged long
How about a potbelly coal stove?
Mark and Luka -
Glad to hear I'm not the only one...........(-:The efforts of governments alone will never be enough. In the end, the people must choose and the People must help themselves. [President John F. Kennedy]
You guys are being cruel.
But I have to 'fess up. My first thought was that I keep the dog out behind the garage where he can't scare the neighbors away...
Anyway, some of us have worthy MILs, may she rest in peace.
Moniter was an idea except for the advancing dementia. Maybe there's a way of shrouding it so she can't get to it to hurt herself.
What about entrances? Will she have to go thru the garage to get into the rest of the house? That could be a point of concern fo danger too..
Excellence is its own reward!
Piffin
I had even worse thought of using the mobile heating/transportation device that is often stored in the garage, but I would not post it.
But I agree that the direct vent heater is probably the best if it is not practical to tape off of the main furnace.
There are other many brands and styles.
What I think would work is the "wall furnaces". Some of them have remote millivolt thermostat so that the thermostat be in an out of the way location where she can't get to it.
And some of them have fans to distribute the air and the case is only slightly warm.
ROFLOL
Not exactly the same thing, but I was thinking...
This IS a mother-in-law we're talking about, right ? Why are you wasting your money on heat ? You should be investing in spiders and scorpions and snakes...
: )
**Disclaimer: Those MIL jokes are just too easy to make. The vast majority of MIL's are good people.**Don't bogart the Ghost
Quittin' Time
Edited 10/10/2002 1:29:45 PM ET by Luka
One other thought.
You did not indicate what part of the country that you are in.
But what about a heat pump. A through the wall or ductless split. It will also take care of AC.
And if it is only for part time use it won't be that expense to operate unless your electric rates are sky high.
Joe,
Don't discount this idea too quickly.
What about a furnace intended for a large RV ?
These run on propane. The new ones are direct vent. The combustion chamber is sealed. Air is drawn in from outside, through the chamber, and then sent back outside.
They put out heat in the same way that residential furnaces do. Forced air, blown over/around the sealed combustion chamber. They are very efficient, and they provide even, quick demand, warm your toes or fingers in a hurry... heat.
Uses a standard thermostat. The one in an RV is not a standard t-stat, because RV's don't always sit level. But a standard t-stat hooks up the same way, and works.
This will not be wasting electricity, or any other energy, when it is not in use.
Don't bogart the Ghost
Quittin' Time
Joe, how about a hydronic system that uses a standard water heater? Relatively inexpensive, quiet and comfortable. JLC has an online article that gives a good overview of a basic system.
...get an up-north attitude...
I think if you read the post over there is a question of dementia. I would go with a monitor Joe. We just bought another one to use in the front part of the house. The one we have now won't heat the whole house. The new monitor has a childproof system on it. This is great for us with a three year old and a year and a half old. With someone with dementia it would help also. That way you set the temp. and it can't be messed with. Good luck!Tamara
From Joe
Thanks for the idea of water heater run hydronic heat. Do you have any idea of the cost o these systems?
Joe, I dug out my receipts, and here's a rough idea-
A 300 ft length of 1/2 in pex was $162.
Water heater was under $200.
Expansion tank was $43.
Taco circ. pump was $135.
Manifold was $9.
A whole slew of small items like the thermostat, air pressurizing assemblies, gauges, adaptors, clamps, clips, ball valves- less than $200, and that's for a whole house. I think that's about everything- we borrowed the tools for making the connections.
Running the tubing for the whole house took DH about 8 hours- that was clipped onto a plywood subfloor. Running in the garage slab (24x24) took two of us about 2 hours, as we had to zip-tie the tubing to the rebar, which took a bit longer.
We have our system up and running as of last week. I am in love with RH. It is sooooo quiet and there are no cold spots or drafts.
We did a thin (1 1/2 pour) layer on concrete over the tubes in the house, and blew about 12 inches of insulation on the underside. For the garage slab, we insulated under that with foam boards, IIRC. If you didn't want to go with either of the concrete options, there is a subfloor with grooves routered into it. A quick search here for "warm board" or "warm boards" should turn up some discussions on that option.
We did ours as a DIY project, so I can't give you an idea on labor. I'll attach a pic or two if I can find them.
...get an up-north attitude...
I noticed that there are no blocks between the studs in the first picture. Were they put in later?
-- J.S.
If you mean along the kitchen wall for cabinets, then the answer is yes....it just took me a while to decide what I was going to do there. ;^)
If you mean along the curved interior wall, then I don't think so.
...get an up-north attitude...
Interesting -- Blocking is required here, both for structural and firestopping reasons.
-- J.S.
Hmmm...dunno what to tell you. It's required on all the exterior walls, and I know we had to put in lots of fire caulk (I'm assuming that's the non-tech term, but it's all that comes to mind...) around any holes.
...get an up-north attitude...