+ Reply to Thread
Results 1 to 8 of 8
  1. #1
    Join Date
    Jan 2008
    Location
    Raleigh, NC
    Posts
    5

    Default Crawlspace insulation question

    Hello! Brand new member here. I searched the archives and didn't find a conclusive answer to my question(s), so I'll ask here. Forgive me if this has already been beaten to death! :-)

    My house is an 1850s farmhouse which has seen multiple renovations and "upgrades" (i.e. its a bit of a mess), located in Raleigh, NC. It has about a 2400 sq ft footprint. It's built on dry-stacked fieldstone piers and a foundation perimeter wall has been built with brick(after the original house was built). There is very little ventilation -- 3 vents on the East side, two on the South, two on the North (both near the NE corner), none on the West where the crawlspace is tightest. The crawlspace is tight on the East side (ca. 24-30") and gets tighter to the West (ca. 12"). There is a vapor barrier down on the ground, but needless to say, there's still moisture. The water heater and plumbing are in the crawlspace, but the HVAC gear & ducting is in the attic.

    Currently there is no insulation in the floors, but the previous owners installed fiberglass batts at some point. They said that within a year the batts were waterlogged so they took them back out.

    In three rooms, there is carpet which we would like to rip out and have the original floors refinished. The current strata of the floors is: joists, heart pine flooring (no subfloor), 4x8 sheets of 5/8" particle board nailed to the pine (with LOTS of nails), padding, and carpet.

    My concern is that when we remove the carpet et al, there will be only the one layer of pine separating the living space from the crawlspace. In addition to being an energy loss, I obviously don't want moisture, smells, and whatever other nasties to come up through the floors.

    So, what would be your plan of attack for this sort of situation? Budget is definitely a consideration -- raising the house a foot or two isn't an option! ;-) I'd like to insulate and isolate, but I don't want create even more of a moisture problem than we've already got. I did talk to one contractor about doing a sealed crawlspace -- he just looked at it and laughed. ;-)

    One option of course is to put new floors over the original, but we'd like to preserve the original if possible. All advice gratefully accepted! Cheers!

  2. #2
    Join Date
    Jun 2007
    Location
    Erie, PA
    Posts
    51

    Default Re: Crawlspace insulation question

    Have 2lb Closed Cell Foam Insulation sprayed under the floor. You will need 2" thick, and this will give you a vapor barrier from the dirt floor in the crawl, and it will keep any nasty air from coming into your home. It will also help glue your old boards down to the rafters so you should have less squeeks in the night.

  3. #3
    Join Date
    Jan 2008
    Location
    Raleigh, NC
    Posts
    5

    Default Re: Crawlspace insulation question

    Is this something an unexperienced but not too hamfisted homeowner can rent equipment and do, or is it something best left to professionals?

  4. #4
    Join Date
    Jun 2007
    Location
    Erie, PA
    Posts
    51

    Default Re: Crawlspace insulation question

    best left to a Pro - you need to know the proper temps, and pressure, how to work and clean the gun etc.

  5. #5
    Join Date
    Jan 2008
    Location
    Raleigh, NC
    Posts
    5

    Default Re: Crawlspace insulation question

    Thanks! I'll investigate it.

    Any other products out there that I might run into for this application?

    Cheers!

  6. #6

    Default Re: Crawlspace insulation question

    You may want to investigate the rest of the house with an infrared scan just so you take the guess work out of the infiltration.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	house.jpg 
Views:	67 
Size:	21.4 KB 
ID:	597  

  7. #7
    Join Date
    Jan 2008
    Location
    Raleigh, NC
    Posts
    5

    Default Re: Crawlspace insulation question

    Thanks for the suggestion, John. Anybody you can recommend in Raleigh?

    I'm getting a quote from a local company re the crawlspace, but they offer only: fiberglass, icynene, and sealing the crawlspace. The gentleman with whom I spoke recommended the icynene over the closed-cell foam -- he said that they don't use cc because it's less environmentally friendly (formaldehydes, etc) and traps moisture which can cause rot. My concern would be if the icynene will let moisture out, it can also let moisture in. What else would it let in? OTOH, I can see that something that would trap moisture & hold it against the wood would be bad. I also value a product that's more environmentally friendly and potentially healthier for me & my family. I think I'm even more confused now! :-0

    He's working up a quote for all three ways he offers -- maybe closing the crawlspace might be the winner if the price is right. It would fix the moisture problem, which would be a plus....

    Thoughts?

    Cheers!

  8. #8
    Join Date
    Jun 2007
    Location
    Erie, PA
    Posts
    51

    Default Re: Crawlspace insulation question

    the gentleman that you spoke with that is offering icynene should be aware that the federal government outlawed using formaldehyde back in the 70's, it is also env. friendly as you can get closed cell foams that are water blown. He is also incorrect about the closed cell trapping moisture. If the closed cell is installed correctly, everything is sealed and no moisture can get in. Also when you have 2" of closed cell you also have a vapor barrier.

    You are correct that the icynene will let moisture in as it is an open cell product.
    Last edited by Bay Harbor Insulation; 01-25-2008 at 02:16 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •