Why do people/builders/HVAC guys put so many furances in garages in homes without basements as opposed to in the crawlspace? And some (waste space by) put them in closets?
I am considering building on a crawlspace and a) don’t have a closet to use/waste and the garage is on the very end of a long house. At any rate I think I prefer teh crawlspace installation. So what are the pros and cons I must be missing.
Then do make transverse or furnances for horizontal installation, right?
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Replies
I'd think they avoid crawl spaces because it's hard to work in them, both when installing the furnace in the first place and when servicing it in the future. I suspect there may be code issues about maintaining a certain amount of working space around the thing as well.
A furnace installed in a garage, except to serve only that garage, is illegal in most jurisdictions, and a bad ideal everywhere.
Crawl spaces are considered unoccupied and inaccessible spaces, and therefore are possibly worse locations for a furnace than a garage. The installation will be difficult and service will be next to impossible, likely ignored and/or very expensive. A crawl space with a dust cap and good access intended for this use could be planned well enough to be a reasonable compromise. And, yes, furnaces are available in upflow/horizontal and downflow/horizontal configurations, you just have to get the drains right.
If you consider having a furnace in the conditioned space of an inside closet as wasting space, just install electric baseboards around the perimeter and do not waste that whole 6 or 7 square feet. Window units are cheap and don't take up much space either. The largest residential gas furnace made, BTW, is 24-1/2" wide by 28" deep. An open door covers service clearance on the front side.
Usually, when inexperienced or thoughtless people design houses that have no space to accommodate the necessary mechanical devices they would like to have, someone has to put them somewhere unintended. The attic, also poor a location for furnaces, is another popular location when there are no good choices by design. Don't force your HVAC installer to have to make a bad choice.
Edited 10/24/2006 1:41 pm by Tim
Interesting that you say that installing a furnace in a garage is illegal in most places. Interesting since nearly 100% of furnaces installed in the NW in homes without basements are in garages (from my observation), HENCE promting my question of WHY? Too which you had no answer as you are apparantly unaware of the practice. Thanks anyway.
As for crawlspaces. What is a dust cap? And yes I have thought of the maintainance issue. It would be a pain to have to go into a crawlspace once a month just to change the filter let alone if you needed a pro to work on it. This is probably the answer as to why builders use the garage. However, I have seen many very nice three or four foot deep crawlspaces, well lit, and with clean vapor barriers on the ground.
Obviously you like base board heat. Strange, but whatever tricks your pony. And apparantly you have plenty of money and space to dedicate living space to a furanace and enjoy the sound of running equipment while eating, entertaining, or watching TV. Also interesting. So I suppose in your case you would use a closet or baseboard heat. As for me, I am looking for options. You have given me food for thought. Thanks.
nearly 100%
wadda mean by nearly???
Have not seen a single clone house in the Seattle suburbs without the ng furnace (or air handler) in the garage for at least 8 years!
One builder up the street had to put in a 6 ft deep foundation wall to meet earthquake spec - actually FILLED IT IN vs leaving a basement or at least a utility room - they even fill in when it could 'drain to daylight'. asked a realtor who said basements dont sell here. Think my house is the only house within 5 miles with a basement.
That's curious...I understand that basements aren't commonly done in some areas of the country, but I don't understand why someone wouldn't buy a house that does have one. Seems like they passed up the chance for some (nearly) free space in the case you mentioned.
Off topic, but I was just in downtown Seattle visiting friends (Capitol Hill) and they have a basement.
My mistake about being illegal. I did answer why, however. No other good choice.
"What is a dust cap?" A thin, concrete slab, poured over a vapor barrier in a crawl space.
"Obviously you like base board heat." That was sarcastic. I do not like electric baseboard heat. It does take up very little living space, however.
I grew up in a very small house, pier and beam construction with a dirt, vented crawl space. The tiny closet that contained the furnace was an insignificant loss to the living space. The closet was located off the cental hallway and the sound of the furnace operating was unnoticeable.
I would prefer the attic over the crawl space, the closet over the attic, and the crawl space over the garage.
Nice reply.
Baseboard takes little space? Well, sure if you don't want any furniture in your house. LOL!
Attic over crawlspace? I hate the thought of the heat losses in the attic. Just does not seem right.
I grow up in a house with a furance in a closet as well. I thought the noise was pretty bad. It probably depends on the furance and teh new ones are probably better than the old ones.
I think Tim was be sarcastic when he said to not waste a whole 6 or 7 square feet of space for a furnace, and instead recommending baseboard heat and window air conditioners. He right, 6 or 7 square feet is not a lot of space. Obviously baseboard heat in a whole house will take up more than 6 or 7 square feet.
i think this thread is one of those classic
" they don't do that where i live " ones
in the NE, the basic heating system is oil -fired hot water baseboard
it is only recently with houses getting Central Air that we have started to see more hot-air heating systems
and , since most houses have basements, this is wher the burner / boiler goes
in those that don't, if there is an arrached garage, that is the likely choice for the furnace
a crawl space with a slab would be good, but it would also be kinda dumb... if you are going to go to that expense, it will probably become a full basement anyway
furnaces in attics... yup, it happens..
and furnaces in closets... you bet
the decision tree criteria should be :... efficiency... service of equipment.... available space... type of system.... A/C included ....
anudder ting.... furniture placement has been fighting baseboard heat since baseboard heat was invented... they both have learned to co-exist in lots of homesMike Smith Rhode Island : Design / Build / Repair / Restore
So this is remarkably timely for me - My wife and I are having a house built, concrete forms were just pulled off the foundation today! No Basement, don't want to use crawl space, no attic available. because of this, we were planning on putting the Propane furnace in the unfinished garage (finished someday), on the common wall with the house. Alternatively, there is a 3'X3' closet in one of the upstairs bedrooms that was in the plans for a second Water Heater. We were not planning on putting this heater in, and using it for storage. Would this be a "better" place for the furnace? Is this advisable/allowable since it is in a bedroom? (could be accessed from the bathroom if need be)
"I hate the thought of the heat losses in the attic. Just does not seem right."No heat losses if you have a condtioned attic space.
Bill, conditioned attic is heat lose! heat wasted! And why would anyone have a conditioned or heated attic if it is truely just an attic. If it is living space then you are back to wasted square footage.
In the past few months, I've been perusing floor plans from LOTS of different magazines & books for a house for my wife and me. What I'm noticing is that only about 1 out of 100 that shows any space for a furnace or boiler and/or water heater. What is with these designers? Are they all from Hawaii where they don't need heat or hot water? Is it just assumed that there will be a garage, crawl space or basement that isn't part of the plan?
To me, this is a huge issues as I'm looking for a small footprint with detached garage. If I have to add a whole room for a heater, I can't use any of the plans I'm looking at.
Here in Alaska, hot water boilers are most common these days as in-floor heat is getting to be the norm. Once you figure for the footprint of the heater, the necessary piping & controls, clearance from combustibles and working clearance, you need something the size of a full bath.
Just my 2 cents.
Reddog
red... my cousin had a fire in his house and decided to move his furnace outside
he now has one of those wood burning boilers in it's own shed about 50 ' from the house... loads the huge logs once a day... and heats a big house with hot water baseboard ( in Michigan )Mike Smith Rhode Island : Design / Build / Repair / Restore
I remember seeing plans for something like that in Mother Earth News about 100 years ago. It would burn just about anything, wood, paper, trash, used crankcase oil or whatever....
Reddog
"1 out of 100 that shows any space for..." That many? This is a chronic failure of architects.
In the commercial projects I design HVAC and plumbing systems for, many "professional building designers" i.e. architects, with many years and even decades of experience continue to design buildings with more thought about what color the carpet will be in the waiting room than what is required to create a healthy and comfortable indoor environment.
Residential plan drawers, call them architects if you wish, are the worst and in most cases and usually plan the building no better than their clients could do without them. Shameful, if you think about it.
I work for an architectural company, and almost without fail, during the first coordination meeting I have to ask, "Where am I going to route the necessary ducts? Where can I locate the equipment? Where can I access an exterior wall for exhaust, makeup air, combustion air and or ventilation (outside fresh) air?" And almost always get the same blank stares and the "Oh, yea, didn't think about that" responses.
The garage option also seem odd from the standpoint that you must lose some heat from the furnance to teh surrounding cold garage.
In all of Canada, you can not have the garage communicating with the house. That means no ductwork, no furnaces, etc. Why, because you could die from the co that your car puts out.
If you do put the furnace in the "garage" it must be in a room that is sealed off from the garage. Exterior weather tight door and all that stuff.
I suspect your codes say something similar.
Code, I don't think so. No requirement for a sealed room. I have seen dozens of furnaces just open to the garage space. NO door, no insulation. Go figure.
"n all of Canada, you can not have the garage communicating with the house. That means no ductwork, no furnaces, etc. Why, because you could die from the co that your car puts out."Properly designed and maintained furnace there is not path for the car CO to get into the house.Not properly installed or maintained you have to worry more about the CO out of the furnace.
If you can gaurantee that the furnace and ductwork is 100% sealed from the air in the garage, fine. But you can't. Owner might take off the fan door and jumper the door switch if it has one. Then somebody starts the car to warm it up. Then they are talking to St Peter.
I know you wouldn't do that, but there are stupid people in this world that need to be protected from themselves. And we need to be protected from them.
If it is sealed, and in the garage, little chance of co from the furnace getting into the house. I have only seen 1 furnace with a crack that let co into the airstream.
Remember, the outside of the hx is in a positive pressure zone and the inside is near negative.
The real problem with the furnace and/or water heater in the garage is when/if the car starts dripping gasoline.
Ozlander
That is why any source of ignition is supposed to be at least 18" above the floor.
Do you know if the 18" rule still applies to the new water heaters with the anti-flashback(?) technologiesI'd still do it, because it seems like with some you'd have to replace the water heater if it "tripped" but am curious.
Youth and Enthusiasm Are No Match
For Age and Treachery
I seem to recall a thread on some board a few years ago. Most if not all inspectors still required it. But don't quote me.
Bill Hartman,
You write that with a "properly designed and maintained furnace there is not path for the car CO to get into the house." Not true. Every residential furnace, as it comes from the factory, has leaky seams. Every furnace-to-plenum connection includes air leaks. Some of these seams are extremely difficult to seal with mastic, even if a competent installer knows about the problem. Researchers at the Florida Solar Energy Center have quantified the problem; since pressures in the supply and return plenum are high, a garage-installed furnace can suck a lot of garage air into the system. See the report at http://www.fsec.ucf.edu/bldg/pubs/cr1357/index.htm
Neither place is good for a furnace. In the garage you have lots of moisture and salt which can rot the furnace. You also have spiders, mice, and so forth. And probably the most important reason is safety. Garages must be separated from living space by a fire wall. Putting ductwork through the wall violates the fire wall unless you also install fire dampers in the ductwork which may not be accepted by some building inspectors. In the crawlspace you have all the moisture problems along with accessibility problems.
Since you are building a new house, your design should accommodate the furnace in a proper place within the home. Not doing so would be not unlike saying you want an outhouse so you don't have to use up your space for a bathroom.
Wayne, mositure problems in a crawlspace for a furnance? If you have mositure problmes in your crawlspace the furnance is the least of you problems or concern in my opinion. If you have acrawlspace you better figure out how to have a dry one.
There will always be higher humidity in a crawl, even where there isn't enogh to be otherwsie significant, it can condense during A/C I see a dozen +/- furnaces in crawl spaces a year, and they always seem to age faster and look crummier.
Youth and Enthusiasm Are No Match
For Age and Treachery
OK, sounds like most don't like the crawlspace option adn the garage ani't mcuh better and shame on builders/designers not allowing for furnances in internal closets.
Square one?
As an Automotive Engineer, I will make the point that modern cars (>1985) will stall from lack of oxygen in a closed garage before they generate sufficient carbon monoxide to kill a person. Several failed suicide attempts have proven this. To succesfully commit suicide by automotive exhaust, it is necessary to "plumb" the exhaust into the car interior on purpose.
If the garage door is open enough to feed the car engine, the carbon monoxide is also disappated.
My furnace is in the garage but, here in sunny, warm Tucson, there are high and low vents in the wall next to the furnace.
I am facing the same question regarding commercially available home plans. Few of these plans show where the furnace, A/C compressor or water heater are to be installed. It appears that it is left to the HVAC contractor and plumbing contractor. This does not inspire confidence in a well built house.
Terry, exactly. The problem is almost worse for the hot water heater. If you think about a crawlspace install then you are limited to the small short units and likely need two of them. At least the furnances can be purchase to be installed horizontlly.
Well, I suspect a lot of these designs are oriented to S Cal or other southern areas where you'd put it all in the attic. I'm remembering that some even put the AC condenser up there.
Seven blunders of the world that lead to violence: wealth without work, pleasure without conscience, knowledge without character, commerce without morality, science without humanity, worship without sacrifice, politics without principle. --Mahatma Gandhi
>>As an Automotive Engineer, I will make the point that modern cars (>1985) will stall from lack of oxygen in a closed garage before they generate sufficient carbon monoxide to kill a person. Several failed suicide attempts have proven this. To succesfully commit suicide by automotive exhaust, it is necessary to "plumb" the exhaust into the car interior on purpose.As a carbon monoxide safety analyst, I will make the point that maybe a garage will be tight enough, and maybe a few have been tight enough, but I wouldn't bet _my_ life on it.>>If the garage door is open enough to feed the car engine, the carbon monoxide is also disappated.Unless the garage door is only open on the bottom: combustion gases are hot, they rise and CO levels will be significantly higher the higher one is in the room.As CO and CO2 levels build, a "clean burning" combustion appliance will start producing significantly higher amounts of CO as the O2 levels diminish.I don't know about auto engines, and whether they will die from oxygen deprivation before or after people will, but furnaces and water heaters and gas stoves will put out huge amounts of CO before the oxygen levels drop too low to support combustion.
Youth and Enthusiasm Are No Match
For Age and Treachery
My dad had a Heil horizontal oil furnace in his crawlspace. (something like 60K BTU) He had it installed new after he gave up on LP wall furnaces and the cold weather funkieness of 160 lb tanks. It worked fine. The house was uncluttered and the furnace was never more than a dial on the wall.
However do you want to be 80 years old crawling with your fat dupa in the finely milled sand mixed with mouse poop every coupla months to just change out the air filter, etc.? In the summer it is cloying, musty, and spiderweb infested. In the winter it is akin to digging out the rutabegas from the winter vegatable mound (what is the word for that?) Whatever the case it is never pleasant.
If you are going to do the horizontal mount then you really need to make it as minimally distasteful as checking your oil in the car. Maybe make a concrete slab beneath the new furnace so you can use a car dolly to scootch over, or dig it out enough so you can just walk with a stoop to the business area of the furnace.
It was always my treat to do the maintenance whenever we came to visit. Maybe that will be a bonding moment for you and your son.
One final thought was that it did start to rust a bit after 10 years. I can't believe that is good for heat exchangers to be exposed to that much dampness. Even if it is a SS heat exchanger.
WOW! what an ugly crawlspace. My parents crawlspace is about three feet deep, pertty good for crawling and working. Bugs? I have never seen one down there. Mice? One or two did find there way in once and did dig into the foam insulation along the wall. I think the entry way was left open over night and that is the only reason a mouse ended up down there.
If I have your experience with crawlspaces, I would be right there with you! Keep me out of there.
But if you have a nice entry way, say 3 by five feet under the stairwell going up to the upstairs, and had the furnance just along side the openning on a small slab, I would think that would not be too bad, even for an 80 year old. Not perfect.
I think the issue here is that as another poster posted, plans DO NOT ALLOW for a furnacne in the living space. ANd it is difficult to modify most of these plans to add a closet for the furnace. Hence the question.
You have Crawlspace, garage, or attic. I think the attic solutions is a waste of heat and even more difficult ot maintain (assuming small 4 in 12 pitch or some such). Garage is a waste of heat, perhaps a fire hazard, and maybe not the best solution if you have a long house (60 or 70 foot hot air run might deliver coolish air at the end of the run). Crawlspace seems like only a maintain issue.
"But if you have a nice entry way, say 3 by five feet under the stairwell going up to the upstairs, and had the furnance just along side the openning on a small slab, I would think that would not be too bad, even for an 80 year old. Not perfect."
Sounds like my childhood bedroom ;-)
This was a cottage. minimalisim prevails in that location. I guess I think one needs to prepare for old age maintenance.Jack of all trades and master of none - you got a problem with that?
booch, what . . . childhood bedroom under teh stairs? LOL!
In NW Ohio:
Don't put it in a crawlspace - crummy environment for the furance and the people who work on it.
Heating gets more expensive every year.
The more comfortable the work environment for the service tech, the better a job he's going to do and the less you'll spend on fuel.
"Garage" installation: ok if its a "closet" in the garage, sealed from the garage, with adequate combustion air sources from the attic and crawl or outdoors.
Uninsulated attic: be the first on your block to see your shingles after a snow. (And usually a tough place for the service guy.)
Youth and Enthusiasm Are No Match
For Age and Treachery