Asked on Jul 08, 2012

Crawl Space Door - Solid of vented??

Jim Ginas
by Jim Ginas
I have air vents around the crawl space that open based on tempurature Question I have is when I had the plastic under the crawl space replaced, the new vents installed, the insulation guy replaced my wooden door (CHEAP from a TERRIBLE Builder, reolaced a metal one, with a cheap hand-made wooden one that was clunky.) SO Question is.... I have a SOLID cover for a door and a vented one. I used to change the door cover out in the summer to the vented one, but realized the metal one I had was solid, SO does it MATTER if the Door cover is solid or vented being I have vents all around the crawl space? I opened it today to read the sub-meter (sprinkler system) and it was nice and cool under the house! Had spiders and they gross me out, but......
Crawl Space w/ solid cover on. (No airflow thru this cover, wheras the Vented cover (screen behind it) obvioulsy allows airflow .
Crawl Space with Cover OFF, sitting at Right side of the pic.
looking to change the faucet to a Hot & Cold faucet I had installed in the back of the house, near patio. Intent is to hook up a shower head for rinsing. Cement put down to allow a solid, clean surface to stand and drains to grass.
  9 answers
  • Jamie D Jamie D on Jul 08, 2012
    Jim, it is important for venting that there is a cross ventilation (one on opposing sides of the space), this allows moisture to be carried outside avoiding condensation and possible compounded issues like mold. In winter as in most places logic would have you close these off perhaps with a panel of EPS foam which should be cut to fit snuggly. This will help keep heating cost down but remember cold falls and only heat rises so if the floor joists are insulated properly there is little need to change this out seasonally. Vapor barrier is imperative to protect the insulation between in between floor joists.
  • Jim Ginas Jim Ginas on Jul 08, 2012
    Jaime, Thank you for the reply. So are you saying that with the insualtion under the house between the floow josts (Terminex and my insulation guy both said it looked good), I don't need to change out the door each season (sumer/winter)? or are you saying I need to put the Vented door on? (Hot & Humid in VA beach area).
  • Jamie D Jamie D on Jul 08, 2012
    vented is best yes, in the extreme hot months especially if you do use air-conditioning.
  • Jim Ginas Jim Ginas on Jul 08, 2012
    ok, Thanks Jaime. Vent cover will be on tomorrow morning!
  • The new theory on this is to seal the crawl space from the outside and ventilate it from the inside. However, if there is no ducts, or water pipes, you can ventilate such as cross ventilation but you must air seal the sills and ideally use a real good vapor barrier near the heated side of the floor. If not air and moisture will be drawn up into the wall areas causing moisture to condense and cause mold. If however you have air ducts or pipes you need to seal the walls of the crawl space and condition the crawl area as part of the building envelope.
  • Jim Ginas Jim Ginas on Jul 09, 2012
    w/ VENTED Cover... thanks for the help!
  • Jim Venting is actually the old way of doing things. You want to seal your crawlspace. Venting can actually encourage an unhealthy crawlspace. Check the Dept. of Energy's site for more information.
  • Energy Carol Energy Carol on Oct 19, 2016
    Please, if you do not use your crawl space for a plenum, 'DO NOT SEAL UP A Dirt crawl. You will end up with so much mold down there that you will all end up sick. There are vents in the crawl to draw the moisture away from under the house. Venting is not the 'old way' it is the smart way. Heavy vapor barrier over dirt under a skim coat. Who cares about the bugs, as long as you don't have anyway for them to get up into the house. Have all of the air leaks around the perimeter of your interior walls sealed, as well as your ducts to prevent them from coming in. It also helps keep the conditioned - either hot or cold air - inside your house, not in the attic or crawl space.
    • Jim Ginas Jim Ginas on Oct 19, 2016
      Thanks Carol. I agree, though what we did was have higher rated Vapor Barrier put down, lifetime guarantee, even if another contractor crawls and rips it.... and a dehumidifer with duct work to the far corner to draw out moisture.... I've had 3 readings and all are under 10% (8 and 9%)..... and these were done 2 in summer and one 2 weeks ago. ** They DO close up the crawl space and in-fact, we have learned the old days of letting moisture INTO the crawl space in hope it makes it's way out another vent are no longer agreed by experts today. man people don't need a dehumidifer, but our readings were getting in low 20s..... water drips out of the external part of teh house like the AC does!
  • Kmdreamer Kmdreamer on Dec 17, 2020

    No if you have other vents you should be ok if it’s closed