Crawl Space Insulation

Need to have my old insulation removed and new insulation put in. Anybody know a good guy to call? Is 2.50$ square foot what I should expect to pay? Been doing the google investigation and thought I’d ask this group. Thanks in advance for any insight.
Chris

Chauncey at Crawl Space Avengers. He may very well tell you that energy savings for crawl space insulation will never exceed the cost of the install. At least not in Charleston…

If I was already insulating. I would look into sprayed in place urethane foam.

I am fragile.
Not like a flower.
But like a bomb.

Yep, as stated, don’t think about payback.

The real issue in crawl spaces is moisture control and controlling air movement into the structure. The “old” thinking was that the kraft backing of the insulation was a moisture barrier. That’s been proven to be false and ineffective.

Then some thought about a plastic sheet barrier attached under the joists, a bad idea. Then came crawl space encapsulation, an expensive and generally unnecessary solution. I say “generally” because some homes have unique issues that it solves. Those issues are construction problems that weren’t properly handled at the beginning. I’m working on one of those now and the best solution would be to leave a candle on the table and go for a long lunch.

For most homes: insulation, a vapor barrier on the ground (plastic) and opening the crawl space vents works great. If there are still problems the next step is to close and seal the vents and install a dehumidifier with a humidistat.

So back to insulation. Anything is better than nothing but it doesn’t do much. The cost of the job is mostly labor so buying R-19 is best. When you sell the house you’ll get dinged if it’s not R-19.

Before it’s re-insulated it’s critical that you use this opportunity to plug all the penetrations between the house and the crawl space. Seal up all those holes: electrical, plumbing, phone, cable,dryer hose pipe, etc. Plugging those leaks will do more for energy efficiency and comfort than the insulation. Use the canned spray foam.

Pioneer 197SF

This is exactly the type of feed back I was looking for gentleman! Thank you!

Karma is 360 degrees

“If fishing were easy it would be called your mom”

[quote]Originally posted by Off the chain

If I was already insulating. I would look into sprayed in place urethane foam.

I second the recommendation for spray foam. I just had the ductwork, and undercarriage of my house sprayed with 2" of closed cell foam. No more critters, no more indoor humidity issues, and the floors now seem even more solid. Won’t have to worry about the fiberglass batts coming out of contact with the floor ever again either.

I pulled down all the old insulation on my own (wouldn’t do this part myself if i did it again…), but having my 2000sft house sprayed cost roughly $4000. Prime4energy was the contractor, and did good work.

After replacing sub floor in a area places, removed fiberglass insulation, sealed vents, installed Dry-Eaze dehumidifier set to 65%. Since we’ve had single digits moisture readings in our joists. The Dry-Eaze unit requires a filter cleaning at 6 months, otherwise it quietly does it’s job. Don’t have my glasses. Hope this is readable.


17’ Henry O Hornet w/ Johnson 88 spl
26’ Palmer Scott project hull
14’ Bentz-Craft w/ Yamaha 25

I’d go with spray foam insulation or I wouldn’t insulate. I went with plan B (no insulation in my crawl space) about 5 months ago and so far I can’t tell that it’s not there. If my floor feels too cold this winter, I will have spray foam installed.

I was having mold problems in the crawl space, so I had the fiberglass insulation removed and the crawl space was treated for mold. So far, so good. The mold treatment guy told me that fiberglass insulation holds humidity and creates a great mold-growing environment in damp places like crawl spaces. He recommended that I leave it out for a year and see if I can even tell a difference. So far, I can’t.

Of course it’s my opinion. Whose opinion were you expecting?

The problem with what you should really do with your crawlspace is you get differing opinions/advice. I have a neighbor that paid through the nose to have his fully encapsulated. It looks like a sterile operating room and he says he wishes he’d done it years ago. All that expense just seems unnecessary. Then you get the polar opposite where some say no insulation but put in a vapor barrier. It gets to a point where you don’t know who to listen to. My floor is built from web trusses rather than 2x8/2x10 joists. I have insulation but after 19 years, it is starting to fall in places. No vapor barrier but, thinking about doing one this winter, probably myself. I can stand up under most of my house so it shouldn’t be too bad. The spray in insulation scares me because you’d never see any “issues” once you spray that stuff in.

“Apathy is the Glove into Which Evil Slips It’s Hand”, but really, who cares?

I understand all the confusion.

There are two groups that are the leading experts on these issues. The Building Enclosure Council and ASHRAE. BEC does building science work. American Society of Heating, Refrigeration and Air Conditioning Engineers covers HVAC and structures. They do all kinds of research and publish great articles, but some are quite technical. US building codes are based on expert advice provided by these groups. But there is always years of delay in making changes.

As part of my former job I was involved with these groups, read the articles and attended educational seminars. The research shows that insulation and moisture control techniques are different based on the conditions in your area.

The advice I provided comes from that research.

As for your neighbor. Yes, what was done works but it is usually significant overkill. Sure he’s happy but… Talk to anyone that buys a boat or a certain gun, and that boat or gun will be the best thing going. Why? No one wants to admit they made a bad decision or that there was a better option. If funds are unlimited then encapsulate.

If not then take it in steps. Use 10-12 mil plastic and put a vapor barrier on the ground. If you rarely go in there and there are no rocks, sticks or things that can puncture the plastic then 10 is fine, the more traffic the thicker you’ll want. If it gets holes in it then it’s not effective. Overlap the seams 6-12", take it to and up the foundation wall and piers a few inches. If you can add some sand or whatever to weigh down the edges it helps to make the seal. The tighter it’s sealed the better, that the magic of encapsulation.

Make sure there is enough crawl space ventilation and leave them open. Yeah, yeah people argue about this. If it makes one happy then close them on real cold days. But remember to open them to prevent moisture levels from rising.

Any existing mold (a fungus) will not be active below 60% humidity levels.

Next step would be to insulate and possibly add a dehumidifier with a

quote:
Originally posted by DFreedom

No vapor barrier but, thinking about doing one this winter, probably myself. I can stand up under most of my house so it shouldn’t be too bad.

“Apathy is the Glove into Which Evil Slips It’s Hand”, but really, who cares?


Oh boy. Following

quote:
Originally posted by PeaPod
quote:
Originally posted by DFreedom

No vapor barrier but, thinking about doing one this winter, probably myself. I can stand up under most of my house so it shouldn’t be too bad.

“Apathy is the Glove into Which Evil Slips It’s Hand”, but really, who cares?


Oh boy. Following


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“Another poon dream splintered on the rocks of reality.” --Peepod 07-25-2017

Bluesky, thank you. I have seen some videos regarding the reinforced vapor barrier available and how some break down over time and the cording gets damp and then smells like cat urine. I want a thick barrier because I walk under my house a good bit. Can you recommend one that will hold up AND not end up smelling like cat pee? I’d never heard of such a thing.

You other Yahoos (and you know who you are) can KMA.

“Apathy is the Glove into Which Evil Slips It’s Hand”, but really, who cares?

KMA?

Just for that, me and 23 hope your hole* crawlspace smells of cat pee

Sircumscibed…

Bonzo been by with Willie after a couple of Miller Lights???

https://crawlspaceninja.com/blog/crawl-space-cat-urine-smell-causes/

What did they do before plastic???

The ENTER-NET Fisherman

quote:
Originally posted by DFreedom

Bluesky, thank you. I have seen some videos regarding the reinforced vapor barrier available and how some break down over time and the cording gets damp and then smells like cat urine. I want a thick barrier because I walk under my house a good bit. Can you recommend one that will hold up AND not end up smelling like cat pee? I’d never heard of such a thing.

You other Yahoos (and you know who you are) can KMA.

“Apathy is the Glove into Which Evil Slips It’s Hand”, but really, who cares?


I use black poly, not sure of the thickness, probably 10-12 mil. I did one 11 years ago and looked at it this past week, still in good shape. The black poly lasts a long time. The clear stuff will deteriorate quickly if it gets any sunlight.

Pioneer 197SF

Good to know, thank you. Don’t want my house smelling like Willi was down there.

“Apathy is the Glove into Which Evil Slips It’s Hand”, but really, who cares?