# Any Benefit to Having a Clean Crawlspace? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [October 23, 2007, 10:52pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767 "2007-10-23T22:52:29Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![fessie](https://avatars.discourse-cdn.com/v4/letter/f/c37758/32.png) [@fessie](https://boards.straightdope.com/u/fessie)\ **Post date:** [October 23, 2007, 10:52pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/1 "2007-10-23T22:52:29Z")
I’m on dust alert over here, I absolutely HATE closing the windows and turning on the heat. :sigh: No matter what I do, my daughter’s room still smells dusty to me and I worry about it because of her asthma. I’m also extremely sensitive to dust. So today I was under the house checking the tape on her ductwork. No obvious holes, but I found a few spaces where there might’ve been gaps. I just slathered duct tape all over the joints. I also found that our dryer duct had come detached, so I fixed that - there’s lint all over the place down there! It would make a great haunted house, very creepy. Is there any point in cleaning it up? What about all the dust, dirt, and plain old crud down there? There’s a sheet of visqueen over the packed earth, it could stand to be replaced (plenty of holes). Is that a good idea? Would these actions reduce the dust in our house? I have to change our furnace filter every month, the thing turns absolutely gray. I have a good vacuum cleaner that I use 2x/wk. ---
**Author:** ![thirdname](https://avatars.discourse-cdn.com/v4/letter/t/d07c76/32.png) [@thirdname](https://boards.straightdope.com/u/thirdname)\ **Post date:** [October 23, 2007, 11:00pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/2 "2007-10-23T23:00:09Z")
Well, when lint gets built up inside a dryer, it’s a fire hazard. I don’t personally know anything about homes or building codes, but I would imagine that if there’s any potential source of flame, a bunch of lint could serve to spread the flame. If an electrical cord was frayed and sparking, for instance, it could light the lint on fire. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [October 23, 2007, 11:03pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/3 "2007-10-23T23:03:14Z")
Benefits of a clean crawlspace? Easier access to things for repair, and less mess if there’s a flood. Fewer monsters as well. I’m still not sure why Stephen King hasn’t written a book called _Crawlspace_. ---
**Author:** ![freckafree](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/freckafree/32/3050_2.png) [@freckafree](https://boards.straightdope.com/u/freckafree)\ **Post date:** [October 24, 2007, 2:56am UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/4 "2007-10-24T02:56:52Z")
[QUOTE=Sunspace] I’m still not sure why Stephen King hasn’t written a book called _Crawlspace_. [/QUOTE] Gaaaah! Thanks so much for planting the idea for tonight’s nightmare. :eek: ---
**Author:** ![Argent\_Towers](https://avatars.discourse-cdn.com/v4/letter/a/e8c25b/32.png) [@Argent\_Towers](https://boards.straightdope.com/u/Argent_Towers)\ **Post date:** [October 24, 2007, 5:27am UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/5 "2007-10-24T05:27:58Z")
More room to hide the bodies in. I remember Bob and Tom had a song called “I Got Friends in Crawl Spaces” about Jeffery Dahmer and John Wayne Gacey, to the tune of “I Got Friends in Low Places.” ---
**Author:** ![tremorviolet](https://avatars.discourse-cdn.com/v4/letter/t/e47774/32.png) [@tremorviolet](https://boards.straightdope.com/u/tremorviolet)\ **Post date:** [October 24, 2007, 3:45pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/6 "2007-10-24T15:45:37Z")
[QUOTE=riker1384] Well, when lint gets built up inside a dryer, it’s a fire hazard. I don’t personally know anything about homes or building codes, but I would imagine that if there’s any potential source of flame, a bunch of lint could serve to spread the flame. If an electrical cord was frayed and sparking, for instance, it could light the lint on fire. [/QUOTE] Yeah, it’s really good the OP found the loose vent hose; there are [15,000 dryer related fires](http://www.dryerbox.com/news_articles/dryer_fire_potential.pdf) (PDF) every year. :eek: Lint is extremely flammable; at the very least, you should get up under there with a vaccuum and clean out the lint. I don’t know if there are any other benefits to a clean crawlspace but get that lint up. ---
**Author:** ![phouka](https://avatars.discourse-cdn.com/v4/letter/p/c5a1d2/32.png) [@phouka](https://boards.straightdope.com/u/phouka)\ **Post date:** [October 24, 2007, 4:18pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/7 "2007-10-24T16:18:47Z")
What’s visqueen? ---
**Author:** ![Missy2U](https://avatars.discourse-cdn.com/v4/letter/m/3bc359/32.png) [@Missy2U](https://boards.straightdope.com/u/Missy2U)\ **Post date:** [October 24, 2007, 4:31pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/8 "2007-10-24T16:31:50Z")
[QUOTE=phouka] What’s visqueen? [/QUOTE] Plastic sheeting. The kind of stuff you’d put over furniture if you were painting, kwim? ---
**Author:** ![3acresandatruck](https://avatars.discourse-cdn.com/v4/letter/3/e79b87/32.png) [@3acresandatruck](https://boards.straightdope.com/u/3acresandatruck)\ **Post date:** [October 24, 2007, 5:07pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/9 "2007-10-24T17:07:59Z")
[QUOTE=fessie] I found a few spaces where there might’ve been gaps. I just slathered duct tape all over the joints. I also found that our dryer duct had come detached, so I fixed that - there’s lint all over the place down there! It would make a great haunted house, very creepy. Is there any point in cleaning it up? What about all the dust, dirt, and plain old crud down there? There’s a sheet of visqueen over the packed earth, it could stand to be replaced (plenty of holes). Is that a good idea? Would these actions reduce the dust in our house? I have to change our furnace filter every month, the thing turns absolutely gray. I have a good vacuum cleaner that I use 2x/wk. [/QUOTE] I’ve been talking with my neighbor lately about what to do about my crawlspace, since he’s an experienced (over 10 years) residential HVAC technician. It sounds like your crawlspace is similar to mine (although I hope yours is taller; mine’s only 12-18" high). Anyway, yes, clean up your crawlspace. If it’s pretty icky in there, wear a respirator while you do it. Personally, I use one of those rubber ones that look a little like a gas mask and has replaceable filter cartridges; I don’t think much of those little ‘nuisance masks’ they sell. Wear eye protection, too, regardless of whether it’s icky or not - safety glasses or safety goggles. This stuff is darn cheap compared to getting junk in your eyes or your lungs. Yes, replace the plastic sheeting. My neighbor says to use 4 or 6 mil plastic (he prefers 6 mil). Make sure there are no protrusions from the packed earth that might cut it before you put it down. Don’t just butt the plastic against the foundation walls, have it overlap up the walls a few inches. If you need more than one sheet to cover everything, he says to overlap by 18-24" and seal the joint with tape. It’s some kind of tape made for the sheeting. He doesn’t like duct tape. AND he doesn’t like duct tape on your ducts. Despite the name, duct tape will always fail. Remove the duct tape when you’re ready to replace it. He uses fiberglass mesh tape covered with mastic, applied generously to ALL joints, whether they appear to have gaps or not. Anything with rot or rust holes should be replaced. If your crawlspace is not heated, he’d insulate the ductwork. It’s hard to say if this will eliminate your dust, as there could be other sources. You could also already have a lot of stuff inside your ducts. But it might decrease the dust and should reduce your heating bills. ---
**Author:** ![fessie](https://avatars.discourse-cdn.com/v4/letter/f/c37758/32.png) [@fessie](https://boards.straightdope.com/u/fessie)\ **Post date:** [October 24, 2007, 7:42pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/10 "2007-10-24T19:42:57Z")
Thanks for the heads-up! Now I see what I’ll be doing for the next month while the kiddoes are at school. Husband plants flowers - I repair/replace ductwork. 😛 **3acresandatruck** , do you have any suggestions as to insulating material? I’d seen notes about mastic, it sounded like some kind of rubber cement to me, I didn’t realize it was a kind of tape. But guess what was already ON our ductwork? Good old gray duct tape! And speaking of creepy crawlspaces, here’s a story I’ve been following from another messageboard (I’ll box it 'cause it’s pretty gross): > [@Creepy and TMI](#): > > [spoiler]Dh and I are remodeling our old house before it gets put on the market at the end of this week. The contractors were there today and tore apart the shower wall while retiling the shower. They found a bunch of stuff in the wall. There was a yellow bra and sanitary pad. The pad was from 1959 and was still in the unopened box. > > There was also a clear plastic bag that was tied shut in a knot. When we opened the bag, there were 3 books; Group Sex, Carnal Knowledge, and The Pleasure of Helen. These books were copyrighted in 1971. There was also a pair of women’s pantyhose and numerous, numerous pictures of a teenage girl. They were taken from our house. It looks like the person taking them was in the bedroom window and behind some big bushes. She is walking on the street and he is in our bedroom window or hiding behind the bushes. The girl being photographed was obviously from a local Catholic high school and is walking home with friends. > > There are also ones of her alone, but they look like she was being photographed without her permission. She is only looking at the camera in one picture and in it, she is holding up her hand kinda in a “stop” fashion. > > Two of the pics are really strange. In one, he photographed another photo of the girl and you can see his testicles. It’s like he put his testicles next to her picture and photographed it. In another, he did the same with his penis. Put his penis near a picture of her and photographed it. > > The boxes from the film were also in the bag and they expired in 1972. > > What the heck is all of this? And what do we do with it? Why the heck was it hidden in the wall? And the bra and pad were not in the bag, but just loose in the wall. The contractor said that other stuff was back there, but started to fall. He did not get it and drywalled over it. Now I really wanna know what else is back there! > > **and then posted later** > > We got to the house and looked in the crawl space. There was a huge pile of stuff and I pulled the closest thing to me…it was a list entitled “how to rape and torture a woman”!!! > > I immediately called 911 and they came. A sex detective came and gathered evidence. They are going to come back later and get more b/c you can see stuff tucked into the wall. But, it is hard to access and getting late! > > They found more panties and bras. The list contained 12 things and it was centered on menstrual cycles…like it said that if the woman is on her period, pull out the tampon and suck on it! There were lots of tampon inserts and douche inserts found! > > The 1st thing on the list was to take the woman into your house by force, gag her, and tie her to a chair! > > _ **and then another update** _ > > The main detective said he is coming back when eh is wearing jeans so that he can get into the crawlspace. We were really, really surprised that they left so much, but I guess the scene is over 35 years old! They said the case was also going to be referred to the cold case unit. The detective did briefly speak about a serial rapist being in the area during the 1950’s who was never caught. They are also doing a title search today to see who exactly owned the home during the early 70’s, which is when the pics were taken. We know this b/c the empty boxes of film were in the sealed up bag and the exp. date was 10/72. > > They said that depending on what cold case comes up with, they may come in with some equipment to see if anyone is buried in the crawl space or basement. Another weird thing…when we moved in 9 years ago, there was an incinerator in the basement. It is still there and the detectives noticed that. > > This really sucks b/c we bought our new house in July and really need to sell the old one. It was supposed to be on the market Saturday. > > [/spoiler] I didn’t find anything like that in MY crawlspace :shudder:. ---
**Author:** ![3acresandatruck](https://avatars.discourse-cdn.com/v4/letter/3/e79b87/32.png) [@3acresandatruck](https://boards.straightdope.com/u/3acresandatruck)\ **Post date:** [October 24, 2007, 9:28pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/11 "2007-10-24T21:28:39Z")
[QUOTE=fessie] Thanks for the heads-up! Now I see what I’ll be doing for the next month while the kiddoes are at school. Husband plants flowers - I repair/replace ductwork. 😛 **3acresandatruck** , do you have any suggestions as to insulating material? I’d seen notes about mastic, it sounded like some kind of rubber cement to me, I didn’t realize it was a kind of tape. But guess what was already ON our ductwork? Good old gray duct tape! [/QUOTE] I’m sorry, I wasn’t clear. The mastic is a kind of glue/cement that you apply over a wrap of tape made of fiberglass mesh. So, you wrap the connections with the tape, then schmear it with the mastic using a medium-width putty knife. For the insulation, you can find ‘duct wrap’ style insulation (rolls of fiberglass that you can wrap around the ductwork) from CertainTeed, Johns-Mansville, Owens-Corning and probably lots of others. You might want to check where the ductwork attaches to the registers, if it’s accessible, to make sure the connection is sealed up tight. Are your floors insulated from the crawlspace? ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [October 24, 2007, 9:33pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/12 "2007-10-24T21:33:54Z")
[QUOTE=fessie] I didn’t find anything like that in MY crawlspace :shudder:. [/QUOTE] :eek: I’ll never make a crack about Stephen King again. ---
**Author:** ![fessie](https://avatars.discourse-cdn.com/v4/letter/f/c37758/32.png) [@fessie](https://boards.straightdope.com/u/fessie)\ **Post date:** [October 24, 2007, 9:53pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/13 "2007-10-24T21:53:28Z")
[QUOTE=3acresandatruck] I’m sorry, I wasn’t clear. The mastic is a kind of glue/cement that you apply over a wrap of tape made of fiberglass mesh. So, you wrap the connections with the tape, then schmear it with the mastic using a medium-width putty knife. For the insulation, you can find ‘duct wrap’ style insulation (rolls of fiberglass that you can wrap around the ductwork) from CertainTeed, Johns-Mansville, Owens-Corning and probably lots of others. You might want to check where the ductwork attaches to the registers, if it’s accessible, to make sure the connection is sealed up tight. Are your floors insulated from the crawlspace? [/QUOTE] Thanks for your clarification! Some areas of the floor were insulated by the immediate previous owner (house is 38 yrs old). The ducts are tucked in between the floorboards, but there’s enough clearance to reach around them so I could wrap something. I was just hoping to avoid fiberglass, may have to get a real mask after all (for my recent adventure I’d just tied an old cloth diaper around my head) (doggone those things come in handy). The duct doesn’t fit tightly in the floor opening, I need to tape that, too. Just call me Red Green! I also put those filter things in the registers but they’re not getting dirty so I don’t think they’re doing any good. ---
**Author:** ![3acresandatruck](https://avatars.discourse-cdn.com/v4/letter/3/e79b87/32.png) [@3acresandatruck](https://boards.straightdope.com/u/3acresandatruck)\ **Post date:** [October 24, 2007, 10:06pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/14 "2007-10-24T22:06:05Z")
[QUOTE=fessie] I was just hoping to avoid fiberglass, may have to get a real mask after all (for my recent adventure I’d just tied an old cloth diaper around my head) (doggone those things come in handy). The duct doesn’t fit tightly in the floor opening, I need to tape that, too. Just call me Red Green! I also put those filter things in the registers but they’re not getting dirty so I don’t think they’re doing any good. [/QUOTE] Yeah, I hate working with fiberglass, too. My neighbor gave me a couple of disposable TYVEK coveralls to use; you might see if you can get a few. You can get them with hoods and feet in 'em. You look like you’re wearing some kind of EPA suit, but it keeps the fibers off your clothes. I’ve never seen register filters, but I’d think that if they aren’t working, they’re just an unnecessary restriction and I’d get rid of them. (Just my opinion there) Remember, we’re all in this together. 🙂 ---
**Author:** ![redtail23](https://avatars.discourse-cdn.com/v4/letter/r/3e96dc/32.png) [@redtail23](https://boards.straightdope.com/u/redtail23)\ **Post date:** [October 24, 2007, 10:10pm UTC](https://boards.straightdope.com/t/any-benefit-to-having-a-clean-crawlspace/423767/15 "2007-10-24T22:10:46Z")
If you don’t want to go as far as the tape/mastic combination, they make HVAC tape that works quite well. It’s a metal adhesive tape. Ask at the hardware store. Around here, it’s called “silver tape”, but I don’t know what they call it elsewhere. Don’t use “duct tape” on your ducts, though - it really, really doesn’t do a proper job, despite the name.