Is there a thread on crawlspace encapsulation?
 

I am staring down the barrel of a new project that is going to slow all other projects down for a short {I hope} period of time. I need to seal up and dehumidify my dirt floor crawlspace.

The wife and I built a single family house in 2002. It's about 1500 sf heated area and a porch that wraps around 3 sides of the house, all within the exterior perimeter of the dwelling. When we built it, we did what was the norm in the area and put it over a crawl space. We covered the ground under the heated part of the house with black plastic sheeting and ignored the part under porch. :o We've been struggling with high humidity under there ever since. All we've done {that we thought was} constructive was install a squirrel-cage fan on a timer to circulate air under the house, exhausting it out a foundation vent. Relative humidity is still a problem at over 80% most of the time, complete with some mold on the floor joists.

I wanted to farm this work out so I could continue with the two other projects I'm working on, but more than $5500 to encapsulate under just the heated part of the house was considerably more than I am willing to pay. :eek: So....

I have this plan that I'm currently going forward with. I've ordered some 12 mil three ply vapor barrier plastic(?) sheeting and the corresponding roll of seam tape and I'm going to put it under the porch area, including going up the inner and outer foundation walls about two feet. I will try and fasten it to the foundation walls with a polyurethane adhesive that comes in a caulk gun type cartridge. I expect that to marginally improve the situation. When that is complete, I will order more of the vapor barrier material to do under the heated part of the house while I address the mold problem.

I'd love to hear from anyone who's tackled this issue already and may have some helpful hints.

Thanks,

Mark

I laid the typical 6mil vapour barrier on the floor of my crawlspace. There were no vents in the space, but if there were I would have blocked them off. I stapled the VB to the header as high as I could possible get it, then jambed some insulation batts against the walls. I didn't bother with any adhesive, just a very large overlap of the pieces.
Photo

Do you happen to know what the humidity was before and after you put the plastic down? Do you have an annual termite inspection where you are?

I ask the termite question because our inspector wants us to leave at least a couple inches between the top of the plastic and the wood so they can see termite tubes if they come to visit.

Uh oh, I hope you weren't doing this during the summer. The dew point of the outdoor air in the summer, in almost everywhere except the desert is higher than the crawlspace temperature. You are essentially bringing loads of moisture and exposing it to surfaces where it will condense and mold.

I assume you know this now as you are on the right track by wanting to seal up and dehumidify the space.

Hi,
You're definitely on the right track IMHO. I think crawlspaces are very misunderstood and cause many problems for the homeowner.

Crawlspaceinfo.com has some great information.

When I constructed our house I was required to "encapsulate" our crawlspace. I threw down some black 6mm visqueen and passed inspection. Now it is sagging on the walls, some spots on the floor have torn- I need to do it properly.

I have radiant floor heat in the floor over my crawlspace, so the floor has lots of fiberglass insulation, but fiberglass insulation doesn't stop airflow, odors, moisture etc., I don't have any of these issues, the floor of the crawlspace does have a vapor barrier and there are no open vents, but the floor should be sealed for energy reasons and an ounce of prevention.;)

My current project is adding rigid insulation below the fiberglass, to add R value and keep the fiberglass from hanging down. When all the rigid insulation is in I plan on using foam to seal it air tight.

Another thing I may do is install Tyvek across the bottom of the joists as an additional measure. I contacted a DOW engineer and she said that would be an excellent application for Tyvek. She explained that basically a floor is just a horizontal wall. IMO the floor cavity should be protected like a wall cavity. I wouldn't want wind and moisture flowing across the back of the sheetrock in my walls, why would I want it on my floor?

The crawlspace is closed off, but air still moves as it is heated and cools down.

I think there would be many benefits to heating the crawlspace. Heat moves to cold, if it is warm in your crawlspace heat is moving from your home though the floors insulation (albeit slowly) into your crawlspace. If your crawlspace is warmer than outdoor it is sucking heat out of your home.

I have been considering ventilating the crawlspace with a heat recovery ventilator/ heat pump. Something like this, but with 110V Genvex Heat Pump and Heat Recovery Ventilation Solutions
The fresh air would take care of any odors; the heat pump would heat the incoming fresh air in winter. In the summer the heat pump would dehumidify the incoming air and provide cool air below your floor which is better than heat in the summer. The unit wouldn't have to be very large, especially in summer. In winter, even a little heat in the crawlspace would decrease the delta T and with lots of insulation, very little heat should get sucked out of your house and into the crawlspace.

Good luck with your’ project. Keep the gap for termite inspection and check out the crawlspaceinfo.com website it has lots of great information.

Thats my plan too. Let us know how it works out!!!!!!!!!!

At my old house I talked to the pro's about my crawlspace.

It has issues with rodents, and just being an unpleasant musty area under the house. It was basically poly not joined at the seams on the dirt, and at the top, it went plywood, fiberglass insulation, floor. The mice and rats found gaps and got into the fiberglass.

Their plan was to come in, open it up as much as possible, tape the poly correctly then pump a concrete pad in place. After that had dried and most of the moisture was gone they'd pull the plywood and insulation out, close things back up but leave the required amounts of venting and then spray foam from the cement, up the walls and then across the floor until it was 100% airtight. Closing up the vents could have been done but by code I would have had to heat the space after that.

They wanted lots to do it. I figured I could do it myself for about $5k. While saving up the money I went nuts with aluminum flashing and steel wool and fixed the rodent entry issue and decided it wasn't worth fixing. I of course didn't have anywhere near the humidity issues you're having though. Being as anal about power usage as I am now, I'd probably do it if I still had the house.

One way to seal up the ring joist/joist/sill area is to spray foam the ring joist to sill plate joint from the inside, add some fiberglass insulation, and finish with rigid foam board. Cut the rigid insulation a half inch or so undersize all around and wedge it in place with small chunks of scrap foam board. Spray foam to seal. The vapour barrier can be stuck with acoustic sealant and taped to the foam board.

Greg

http://i194.photobucket.com/albums/z.../P4130243a.jpg

The vent fan in my crawl space is pulling air out from under the 6mill poly via a drain tile that is under it, this is to keep the foundation drier so it doesn't crumble, it tends to exhaust very humid air and pulls the air away from the crawl space instead of pulling more moisture in to the crawl space, that fan is then on a humidistat so as the crawl space humidity goes up the fan kicks on.
Our plastic sheeting is foamed around the outside edges with expanding foam and polyurethane calk in other places, the caulk does a much better job of gluing and sealing.

My next plan is to have a timer switch installed as well so that the fan kicks on once a day no matter what the humidity, just because the humidistat is on the non vented side of the plastic.

As I said earlier, I ordered the vapor barrier plastic material and a roll of tape {on Wed, 4/11}. Americover.com sent me an email with my UPS tracking number on Thursday, 4/12 proclaiming my order had shipped and would be delivered on Tuesday the 17th. I checked the UPS site along the way and it said my order was on schedule for Tuesday delivery. So last night I got home with great anticipation. I didn't see my vapor barrier when I got home, but my wife points me to a shoebox size package. 3 lbs. Box 1 of 1. :confused:

I call Americover and spoke to a polite lady named Tammy. It seems my tape shipped from their location and the vapor barrier material drop ships from maybe Illinois. She wasn't quite sure of that, but it shipped yesterday and is scheduled for delivery this Thursday, the 19th. It wasn't like I planned to install it last night so after a moment of reflection, it was a silly kind of funny. Let's hope it comes tomorrow. I do want to get it at least mostly installed this weekend.

OK, I was wrong in my previous post when I said they told me my order had shipped complete. I assumed it shipped complete because I did not scroll down on the UPS website after I input the tracking number and saw the expected delivery date. I tracked it again after I thought about it, and I'd already posted the previous comment. Turns out that in the tracking info, it showed 1 package shipped that weighed 3 pounds. Since their website said the vapor material I ordered weighed 88.01 pounds by itself, so had I paid attention, I would not have made a negative comment about Americover.

Now, moving on a bit. Last night I got home and the other package had arrived, a dandy of a roll of vapor barrier material! The packaging consisted of wrapping medium weight corrogated fiberboard {cfb} around the material to cover the long sides and barely any cfb material wrapped over the ends of the material. It didn't look like it hurt the ends to be exposed, but there was a spot on the side of the roll where the cfb was gouged. The vapor barrier material was skinned, but not punctured. I would call that a testament to the puncture resistance of their 12 mil thick material. :thumbup:

Now I have a project for this weekend. I hope to get most of the under porch work done Saturday, a rather tough time table for me because the wife has other plans for me after about 1:30 pm. Oh well, I have the rest of my life to complete all of my projects.

This is going to take a bit longer than I anticipated. I got my nephew to help me and we went under the front porch and measured for the first piece. I also noted how much broken concrete block and rock was left under there from the original construction. :eek:

Anyway, after we got out from under the porch, we unrolled some vapor material and cut a piece 54' by 10' 6", folded it in half lengthwise and rolled it up. When we went back under the porch, we carried a 5 gallon bucket for hauling out block and rock. {I should mention that we have 33" headroom under there, so it could be worse.} A couple bucket loads of rock and the situation looked much better on that front. The dirt was heaped up down the center of the under porch area from where it had been dug out to build the foundation. Using a shovel {digging with the blade end upside down was the only way to use it} and a steel rake, we loosened the dirt and raked it out to level the area some. It helped. We have ~ 7' wide area to cover and are going to roll some up the wall and secure it. BTW, folding it in half was a bad idea. It was hard to unfold and tug into position. Next piece will be folded for easier installation.

We quit after about 6 hours work, because I just am not up to more heavy, bent over work in one days time. :o I felt way too bad Sunday to go back under. I hope to do more this evening and I'll download a couple pictures to show my progress and my biggest mistake. It happened at the intersection of a roll of plastic and a 500w halogen floodlight. Oops.

More soon.

OK, I've recovered a few pictures and wanted to put them with the appropriate post. A look at the way the Vapor Barrier Material {VBM} was shipped, after I peeled the plastic loose from one end. Rolling it out on the garage/workshop floor and finally where it spent a few moments too close to my halogen work light while my back was turned. :eek:

Sorry to be behind the power curve on posting pictures. Our Kodak 7mp camera quit taking pictures saying the internal memory was full. I figured I could just download the SD card for the pictures. It's a 2 GB card and it was full. :eek: 861 pictures! Not one from this project. :mad: After I downloaded the couple of pictures I had not already moved to my PC, I deleted all the others and then looked at the pictures in the cameras internal memory. They are all there, I just have to read the manual to remember how to download them.

On Monday evening, we took another piece of vapor material and rolled it out under the side porch. That area is about 3' wide and the height varies from the 33" of the front porch height to about 60" or so where it meets the back porch. I had taken the 54' long, 3' wide scrap piece I cut off of the piece under the front porch and cut it to its 32' length for the side porch. I took the 22' remainder and overlapped it by 6" lengthwise and taped it front and back. Then I unrolled another 3' from the roll {remember, the roll is 13'4" wide} and finished the remaining 10' from that piece. This left only a small amount of scrap that I'll probably use around a pier under the house. After taping the pieces together, I had a piece 32' long and 64" wide. Laying it face up, we rolled both sides over so that the two side portions would rest on top of the portion that would lay on the ground. Sorta' like /__\. Then we took that under the house and rolled it out. Much, much easier than folding it in half and being on top of it while trying to unfold it.

My nephew worked under the house yesterday, starting before I got home. We are pulling all the fiberglass insulation out from underneath, rolling it up in as tight a roll as reasonable, taping the rolls and stuffing them in 30 gallon trash bags. While there is some mold on the floor joists, it's not as bad as my fears had me expecting. Still, I have great {read: expensive} plans for under the house and it does not include 90% or more relative humidity. If all goes well, next week the Spray Tech guy will spray 2" closed cell foam on the underside of the floor and coat all the joists with a thin layer just as a way to keep moisture off the floor joists and rim joist.

If I haven't shared what the driving motivation is behind this work, I am planning to build a new solar array to expand on the 1050w my wife and I already have. The inverter and a breaker box is going to be mounted under the house. The underfloor area is always cooler in the summer and warmer in the winter, so it should make life easier for our Sunny Boy. :D

I added this picture of my nephew Daniel and myself taping together the piece of VBM that goes under the side porch.

Just a heads up. Tremco is about the only thing I have found to reliably adhere to poly

Dealing with these kinds of crawl spaces is always rough and I have yet to find an approach I like. And I've tried them all.

I'm not familiar with Tremco, so I suspect I'll have to Google it soon. The two websites I looked at for the vapor barrier material both showed using a polyurethane adhesive that comes in a caulk tube to hold the material to the walls. I bought several tubes this past weekend. The websites and the adhesive instructions still call for mechanical fastening while the adhesive cures {24 hours}. They show drilling 1/4" holes in the blocks every foot or so and sticking in a little plastic fastener.

The fastener looks like something you'd find holding upholstery trim panels in place in your car.

What I usually end up doing is gluing everything together with Tremco (which is an acoustical sealant) with an overlap of about 2' and French seams, running the VB up the wall, gluing it in place and the spray foaming the wall from floor to band joist. It blows. I think if I had a house like this I'd put down poly and pour a slab over it.

I have thought about that, too. :o It's just a good bit more money than I am willing to spend without trying other {possible} solutions first.

We have a strong room under the back porch and our plan, as of about three weeks ago, is to dig out some dirt from the door to the strong room and pour it in concrete. That's no where near the top of the to-do list, though. I have made commitments that absorb the vast majority of our savings, and to commit to more would not likely be wife-friendly.

I looked up the Tremco website and there is quite the selection of products available. When you referred to using the Tremco to bond polyurethane, did you mean poly to poly, poly to the block wall or both?

Poly to anything. Tremco is a great product. It remains sticky even after decades and it sticks to anything.

I was trying to find information on this stuff and I'm seeing tons of products but no acoustical sealant. Which item should I be looking at from their site?
Products - Tremco Commercial Sealants & Waterproofing

Tremco Acoustical Sealant - Tremco Commercial Sealants & Waterproofing

There are other acoustical caulks but Tremco is a pretty popular and time tested one. I like to use it for all work with poly and any indoor caulking where there will be no painting or touching. You actually might be able to paint it. Not sure as I never use it for those purposes. I think its intended purpose was to seal corner seams in drywall when there is resilient channel behind the rock so the wall can actually move a little bit.

Went back and edited posts #12 & #13 to put in a couple of pictures. The old SD card is dead, but I had a different small capacity card that I used to transfer pictures after we got home from church last night. No actual progress to report.

Like most everyone else, there's not enough hours in the day to accomplish all I'd like to. If you occasionally look in on our garage / workshop build, you know it's going painfully slow, too. Until this project is finished, next to nothing happens on that project. :(

I have a bit more work done under the house, so I thought I'd post a few pictures. The barometer is to show what I'm up against. If you can read it, you'll see its around 80% relative humidity. After I was working a few minutes with a big fan on, it went to about 90%. :(
The second and third pictures are me rolling insulation up to get rid of it. I found that by staggering the strips of insulation when I laid them out before rolling, it would leave only a little fiberglass showing when I taped the ends up. I took the rolls and stuffed them in 30 gallon contractor bags and threw them out. 29 bags of wasted money when we built the house. It would have been nice to known a bit more before we built it this way. Oh well, life goes on.....
The under floor shot shows some of what I have to clean up. On a couple of joists, if you look close you see a light "dusting" an off-white to green color. Mold, of course. The darker streaks a couple joists farther back are the more worrisome parts. All of these are on my to-do list to clean with hydrogen peroxide before the spray foam guy shows up.

We're ready for getting foamed! It was almost 11 pm when I finally came out from under the house feeling a sense of accomplishment last night. I used 3% hydrogen peroxide, straight out of the bottle to remove the mold from the floor joists, and added a little distilled vinegar until I ran out of the vinegar near the end. {I got that recipe for mold removal from a Google search.} I did some by soaking a rag and wiping it, some by using a spray bottle to apply it and then wiping it. It looked a little better as soon as I finished wiping, but it is amazing the improvement you can see the next day. :thumbup:

My foam contractor will either be out this afternoon or tomorrow, which explains the late hour last night. Will post my impression of his work and maybe a couple of pictures when he's done.

I'd watch and definitely inspect his work after the fact. It seems to be incredibly common to have issues with not enough insulation being sprayed (or blown). I think Ryland had an issue with a spray foam contractor. A coworker of mine had issues when he built his house as well. He specifically said he was going to inspect it afterwards and they still blew his attic pretty short in places. They ended up having to come back and blow more in loosing any money they probably would have made on the job.

Count on me inspecting before paying, and the contractor knows this.

The guy who sprayed the garage / workshop project {different contractor} missed the cavities over the door and windows because they only sprayed while standing on the floor and you had to spray downwards to get those places. Because he sprayed more than I paid for in a lot of places though, I ignored it and used several cans of spray foam to make up for it.

I don't intend to go behind and try to foam any gaps under the house though. Further, I don't know if "Great Stuff" is open or closed cell foam. :confused: Since open cell allows moisture to pass, it is absolutely unacceptable in a crawlspace environment and I won't chance that.

I thought Great Stuff was closed cell, thanks for the correction.

EDIT/ADD: http://building.dow.com/na/en/produc...windowdoor.htm
Great Stuff Windows & Doors is closed cell as well as most, if not all, of their products.

Oops, I did not mean to infer that I knew it was open cell foam. I do not know one way or the other, I am just not willing to chance it. I'm editing the post to make that clear, thanks for pointing this out. :o

This is what I {think I} know. When the foam guys came out to spray the garage / workshop project walls {just the downstairs part has been foamed so far}, I asked them how I could tell that they were spraying the closed cell foam I was paying for, besides me looking at the barrel the hoses were connected to. I like his answer. He took a piece of trimmed foam {it was a different color from what he sprayed for me}, handed it to me saying it was open cell foam. The open and closed cell distinction is the amount and size of any air pockets in the foam. He asked me to mash on it, or squeeze it. I did and found it fairly soft/pliable. Then he asked me to mash or squeeze the foam he sprayed on my walls. They had already trimmed a couple of places that were too deep for the 2x6 cavity and I found that piece was more firm than the one he gave me at first.

That said, the areas I used Great Stuff to fill in over the windows and side door felt like open cell foam to me. There are several varieties of Great Stuff in stores. One said "big gap filler" while another says "minimal expansion." AFAIK, they don't say open or closed cell on the can, but if they did, I missed it when I read the label.

Great Stuff is next to solid and its outside is goo so if it is open-cell, the outside forms a barrier unless you trim it after it has been curing. I've used this other stuff that was water soluable, DAP in the blue can and it is softer and more fragile and I thought that stuff was open cell. It has a warning not to trim it after it dries, so I 'machine tooled' it with my finger after I sprayed it in place but it still has that 'surface film' to it but it cracked over the few weeks before I put the window trim back on.

If you squeeze Great Stuff once it is cured it is squishy and seems to try to spring back to its previous position as long as you don't mash it too much. Probably 90% spring back from a 50% squeeze on a 1" glob.

EDIT/ADD: http://building.dow.com/na/en/produc...windowdoor.htm
They say Great Stuff Windows & Doors is closed cell. It's what I used, as well as a different no-warp less expanding stuff in a purple container that was a white foam but just as stiff once cured but I haven't found that one for sale in a few years. I used fireblock which is also closed-cell. Big gap is closed cell(never used it though, haven't had a use)

They sprayed it Thursday afternoon, but getting pictures was out of the question at that time. The fog of foam hadn't settled down for several hours. I did go back and take a few pictures this weekend. They did a pretty thorough job, covering almost everything that looked like wood. {They even foamed around a few block penetrations where pipes came through.} There are a few spots that do not look to have been sprayed 2" thick under the floor and many that look more than 2". I also noted that since this foam came out ~ white, the light travels better under there. Of course, any wiring tacked to the floor joists got foamed as did a good deal of cpvc piping.

We also have two junction boxes with duplex receptacles and another with a light switch. They foamed all that. :( They did clean off the light switch when they were done, and since there were extension cords plugged into both sides of one duplex receptacle, it survived intact. The other one......, well that's picture three after I scraped some of the foam off the lower part of the receptacle. I decided it wasn't worth the effort since the foam went down into the openings, so I scraped off the foam enough to replace the receptacle. This time I put a cover on it. I hadn't bothered with a cover the first time. The light switch and other receptacle box had covers on them all along.

All in all, we are pleased. The floor joists were clean and looked new from being wiped down with peroxide before they sprayed and this foam job should provide many years of protection against moisture. I still need to finish doing the vapor barrier. Not what I'd call a fun task, but at least I have most of the material to do the job and while I'm doing that I'll start saving money for the next project.

Well, looks like I'll be taking my barometer from under the house and putting it in the attic for a few days to watch the humidity range up there.

Is that really 2" of foam? It's hard to tell from the pictures but it looks like a lot less. Still it should be a pretty good vapor barrier even if it's only less than 1".

I believe it to average around 2" of foam. I'm certain it is less in places and more in others. Still, I'm pleased with it overall.

I had to order the pins to hold the vapor material to the concrete block and they have arrived, so I'm running out of excuses on why I'm not back under the porches securing the vapor barrier. I'll likely be back under there starting tomorrow evening after work.

I have one final plan for improving the crawl space that needs to happen before we build our new solar array. We are probably going to pour a concrete floor from the entry to the crawl space to the storm shelter and add about 2-3" of concrete to build up the threshold. Then we'll have another door made to fit the new slightly smaller opening and that should eliminate water seeping in from under the door.

A little more headway this weekend. I bought a 5/16" masonry bit to drill holes to put the pins in to hold the vapor barrier while the adhesive cures. The first thought was to drill the concrete blocks at 2' intervals. Before I actually started drilling though, I noticed where the pest control folks had drilled the mortar joints in a number of places to inject their chemicals a long time ago. I decided that must me an easier way to keep the holes in a straight line and couldn't be any more difficult than a concrete block to drill.

I'm real glad I did it this way. The mortar joints are easy to drill. :thumbup: It did not take but an hour and a half to drill all the holes I had planned under the front porch. OTOH, I read the instructions for the polyuerethane adhesive and now I'm going to have to find a vapor mask. I don't want to risk my health using several tubes of that stuff in an area with minimal ventilation. I have a couple of alternative ideas if I can't find a mask online.

One alternative is to put my fan {a commercial grade 36" fan} so it faces as close as I can get it towards the porch and set it on high. Then pull out the foundation vents to allow a decent outlet for the moving air. The problem is, the fan would be placed at the back end of the side porch and would blow down the 3' wide side porch {~ 31'} and then bounce around to go under the front porch which is 52' long and 7 1/2' wide. I don't think even that high powered fan would put that much moving air at the far end of the front porch.

Alternative number two is use the old masks from my C-pap machine. They are designed to be run overpressurized and the excess bleeds out of the mask. I'd need to run two of them through separate 1" vinyl hoses. I figured I could cobble up a manifold of sorts so I could pressurize it with the leaf blower. The down side is that it would take a good 60' of hose per mask because the blower would have to sit outside the foundation in clean air.

I'd love to hear other ideas, including what type mask you may have used before.

Glad to see you're still plugging away at this MAJOR issues for your health and well being.

Some ideas I have about your work place IAQ: Get a good respirator. It doesn't have to be over the top in price. Any could work. Just get the appropriate cartridges. The only advice that I honestly can give there is that if you can try multiple brands for 4 or so hours you will know which will fit your nose best. If you only use it for a couple hours here and there it shouldn't matter at all though. Me, I hate mine. It begins to squash and hurt my nose after several hours. You will use it many times in the years to come and be glad for it over a dust mask. Next, if your sealant is so hazardous I suggest you depressurize the crawl space to exhaust it. Pressurizing a contaminated area is a no no. Even though you had your floor spray foamed some funk will make it's way up. If you suck it out you will know exactly where it's going. BTW, WTF is the story with this insane sealant?

If you really want to build a pressurized mask I can give you some simple DIY tips I have used in the past, but if your sealant needs that kind of care I suggest you just use spray foam instead. Because it works just as well.

I tried contacting Loctite yesterday and asked about their recommendation for a mask and got no helpful response. I looked up 3M and perused their masks to see what they offered that was helpful. I'm sure of only one thing, and that is I don't fully understand what hazard I'm up against. It may or may not be formidable.

I am now assuming though {I hate to do that} that an organic filter mask is probably what I need. So, I'll pick up a new set of filters for my filter mask and buy another filter mask for my helper to wear. I am also going to run the fan to ventilate the area as much as I can. I have to blow air in, because I can't physically get the fan close enough to use it to exhaust the air. And like I mentioned previously, I plan to remove the foundation vent louvered screens as well.

I'm use to wearing a mask and don't find a well fitting mask to be a real problem, just a minor nuisance. I'm retired USAF and had to wear a gas mask and charcoal suit a number of times, hours at a time in really cold and really hot conditions. This is a walk in the park compared to that! :D

When I had my crawl spaces foamed we had a bid that said 2" of foam and we found a ton of spots that when poked with a 2" chunk of wire turned out to only have 1/4" of foam and a hand full of sill boxes that they missed all together, needless to say they came back and fixed it.

as for vapor masks, most masks have an option for a hepa filter or a vapor filter, I've used the vapor filter for all kinds of nasty stuff, spraying paint was the worst and with those filters you can not smell any of the solvent.

That's the direction I thought I'd go, with the vapor filters. I just stumbled when the filters say "organic vapor." Organic vapor just doesn't sound like what I was expecting to need.

OV cartridges are what's used for spray foam and chemical fumes. The next step up is a pressurized mask, which is obviously worlds better but probably unnecessary in this situation.

And if you can get a fan to blow air in why can't you simply turn it around to suck air out?

The porch is on three sides of the house. I {think I} have to place the fan at the end of the back porch to blow up the side porch and let it bounce air into the front porch area. Reason being, we have a water faucet that is fed through that side under-porch area. The pipe is about 24" off the ground where it passes through. There's about 42" headroom at that particular spot and the fan is 36" diameter. It won't fit under or over. :(

I would definitely be happy to hear a reasonable way to fashion something that would make the fan more likely to draw air from the front. It's just my finite imagination says it would draw too much from around the sides of the fan to make a meaningful difference from the front porch. If the fan wasn't so powerful, I wouldn't expect much flow into the front porch area. If you have a plan to make it where I can draw air, please share, I'm not too stubborn to entertain something new to me, and I don't have a case of the "not-invented-here" syndrom. :p

Understand that I have to be able to put the fan in place while I'm under the side porch and it is under the back porch. Assume the back porch area is about 35" wide and at the corner where the fan would have to sit and there is about 60" headroom. The ground slopes upward from the back of the house to the front. Where the faucet pipe crosses is about 42" headroom and when it gets to the front porch, the headroom is down to 33". Access to the underporch area is through a 36" wide x 54" tall door.

I just got the response to my email to Loctite about the best way to work around this product. The response is from the actual manufacturer. I copied and pasted it below:
__________________________________________________ __________

Pro.Products@us.henkel.com
8:01 AM (9 minutes ago)

to me


Mark,

Using a fan directing the curing vapors outward is the best solution. The cure time will be 24 to 48 hours.

Thank you,

__________________________________________________ _________

It appears they aren't as concerned about it as I am. I'm not sure if that is a good thing or not.

S-F: this does not mean I am disinterested in your fan drawing air technique. I'd like to be able to expand my knowledge base and I'd like to at least be able to give consideration to your method to draw air through. The technique would also work to do a "blower door" test on my house, I'd think.