Furnace installed in crawl space - Contractor Talk - Professional Construction and Remodeling Forum

J-Peffer · 07-13-2009, 05:43 AM

I've some how been elected to over view some projects for a customer on a foreclose home.

HVAC is certainly not my field of expertise, it's my weakness!

When reviewing her estimates, I've noticed all the plans for the work are different.

Most want to install on the main floor.

She has a crawl space, that does have some moisture issues, because of the low lying ground.

Would a suspended (from floor joist) furnace be an option with the moisture issues?

My concern is the noise from the furnace on the main floor.

Thanks for any guidance

NickTech · 07-14-2009, 07:08 AM

not if installed properly with the right vibration eliminators and some insulation over the top of it as a sound buffer and some fire retardant drywall. the moisture is a different issue. usually the right type of ventalation keep it down to the managable level.

J-Peffer · 07-14-2009, 03:54 PM

Quote:

Originally Posted by NickTech

not if installed properly with the right vibration eliminators and some insulation over the top of it as a sound buffer and some fire retardant drywall. the moisture is a different issue. usually the right type of ventalation keep it down to the managable level.

I was thinking along the same lines, I'm not sure if she realizes it or not, but I brought it to her attention today, that she has serious water problems in the basement. After a good hard rain, there is normally about a foot of water down there in the crawl space. It's already caused dry rotting issues with the poorly constructed floor joist and most of the sill plates.

With that much water, I'd want the HVAC company to sleeve any duct work down there, just because of the quality air issues that could be run into. Would probably run a truck, and sleeve it, and run flex off that.

**genecarp** · 07-14-2009, 04:06 PM

Not a good idea, most towns dont even allow a furnace in a crawl space, a furnace needs to be EASILY accessable, When a plumber shows up to do service he does not want to crawl into a 3' damp area to do his work. G

JonM · 07-14-2009, 04:13 PM

http://www.kalispell.com/building/do...rawl_space.pdf

beenthere · 07-14-2009, 06:34 PM

If it floods the furnace. She will have a really big repair bill.
Warranty doesn't cover water damage.

NickTech · 07-14-2009, 06:35 PM

Quote:

Originally Posted by genecarp

Not a good idea, most towns dont even allow a furnace in a crawl space, a furnace needs to be EASILY accessable, When a plumber shows up to do service he does not want to crawl into a 3' damp area to do his work. G

thats for sure!
have you considered putting it outside in a small prefab shed ?

**loneframer** · 07-14-2009, 06:53 PM

Quote:

Originally Posted by NickTech

thats for sure!
have you considered putting it outside in a small prefab shed ?

Something like this.

rbsremodeling · 07-14-2009, 06:58 PM

You have an outhouse?

J-Peffer · 07-14-2009, 11:01 PM

Good points, I know I would not like to service a furnace in a location like this. It makes changing a filter a real task even.

It could be installed on the main floor, but noise is the biggest concern there.

One HVAC contractor suggested a 2 stage furnace, that would run quieter unless it's REALLY working.

I thought framing it in with 5/8" drywall inside and out, dense insulation and maybe some a few rolls of cork to deaden the sound. But putting it outside of living space would be really ideal. The garage is attached, also, but the duct runs could get tricky running it from there.

MechAcc · 07-15-2009, 07:01 AM

Quote:

Originally Posted by J-Peffer

Good points, I know I would not like to service a furnace in a location like this. It makes changing a filter a real task even.

It could be installed on the main floor, but noise is the biggest concern there.

One HVAC contractor suggested a 2 stage furnace, that would run quieter unless it's REALLY working.

I thought framing it in with 5/8" drywall inside and out, dense insulation and maybe some a few rolls of cork to deaden the sound. But putting it outside of living space would be really ideal. The garage is attached, also, but the duct runs could get tricky running it from there.

Properly sized duct work and grilles should reduce or eliminate noise. Using a variable speed blower system will really reduce noise.

Installed a Trane XV90 system in my home in 95 and it is quiet. If it is a concern the walls of the mechanical can be insulated to reduce noise to attached rooms.

Is it me? It seems that horizontal installed furnaces seem to die faster.

J-Peffer · 07-15-2009, 12:44 PM

Decided today, that I'm just going to walk away from this one.

I did the roof, siding, windows, soffit, fascia, window wraps and have the job complete. But over seeing this type of stuff is just not for me to sort out.

I'm fairly knowledged in most fields, but I'm finding I can't work with someone, unless they are willing to let the install be done to my standards.

I have a contractor, who's willing to install in the attached garage, but understandably, the duct work will cost more (cause there is more of it) but she want's it in the wet crawl space, or framed in between the kitchen and the dinning room.

I've explained to her, the old 2x6 floor joist, are not pressure treated, and are dry rotted, and very bad. She does not want to address it. I won't frame over them, and I won't do the work with out permits to cover my tail.

I'm booked with good profitable jobs till the 2nd week in September, I only work until November 15th. Someone else can handle this one