Considering methods on how to airseal my addition.

I originally looked at a DIY closed cell foam kit to do a flash and batt (cellulose) on the outer OSB and studs on my double stud wall. Downside is those kits are expensive and I would need at least two to properly do it.

I then looked at the EcoSeal product and successfully took the Ecoseal test to become a certified installer. However, from what I understand a regular harbor freight piston type sprayer might not cut it for spraying the stuff. The stuff is only available in 5 gallon buckets at $200+ a bucket. I dont think I would use the whole bucket and the rest could be waste. There is also  the additional hoops I still have to go through in order to order this crap. I am sure it is a minimum order too.

I have considered individual tubes of caulk but that will take forever.

I read where some person successfully mixed caulk with latex paint for a paint on or spray on solution. 

Am I missing any other DIY or advanced DIY options? I also briefly looked into rigid foam cut to size with the sides spray foamed or caulked. Thanks.

Off topic - Also, anyone know of a good source of 2inch rigid foam? Lowes and Home Depot doesnt seem to carry the stuff and the 84 lumber place I talked to carries no insulation.

Also, anyone know of a good source of 2inch rigid foam? Lowes and Home Depot doesnt seem to carry the stuff

I have never seen them not have it. But as Dana would say, check for used insulation.

I had the local NOARK Foam make my underslab EPS foam to my specifications. They manufacture and supply Foam-Control EPS products. You might see if you can find a manufacturer/distributor for http://foam-control.com/ in your area. They manufacture large EPS foam blocks approximately 2' high x 4' wide x 16' long. They can then hot-wire cut the foam to any size/thickness needed. I requested a non-standard foam (Type IX with borates), so the only catch was that I had to purchase an entire block. In my case I needed ~1-3/4 blocks of the foam, but ended up with 2 whole blocks cut down to the thickness I needed. I had extra foam left over that was used elsewhere in the build. It was still far cheaper than buying this stuff from a retailer.

As far as air sealing goes, you might research elastomeric roof coating and see if that might work for you. The better quality (10 year warranty) stuff costs ~$100/5 gallon from Lowes or other places. I have used the following product (Black Jack Ultra Roof 1000) for an ICF basement wall waterproofing membrane primer and for sealing around my ICF window and door openings. It has good adhesion and is tough and flexible.

http://www.gardner-gibson.com/linedetails.aspx?id=87

Thanks for the info. Also looked at that for making the south side of my roof white.

Also, found out why I cant find rigid foam anywhere here. Virginia only requires R13 and no builder right now will exceed the minimum... what crap no one charges the minimum!

Foam Control has two plants in Virginia per their contact page:

http://foam-control.com/contact/contact.asp

Found a source of thicker foam. Apparently, our lowes just does not carry it but another one in the city does. They can arrange to get a quantity delivered if I want to purchase it.

Looked up the Black Jack Roof sealing. Actually, not quite interested in using it on the South side roof of my house (back not visible from the road and takes all the hit from the sun.) Anyone else use this stuff for an airseal? Is it too thick to put through a sprayer? I like the idea with the ecoseal stuff of putting it through a sprayer and pumping it into the seams at 1800psi. Would a 5/8 hp sprayer do the job with this stuff? Thanks.

I would be careful to check the vapor permeability rating of any spray on product.

Looked up the Black Jack Roof sealing

Asphalt and mineral spirits to seal seams? Is that considered green?

Actually, the black jack stuff looks like latex. At least the latex white roof product is what I am considering. I am also only going to spray on seams so I am not worried about vapor perm. Thoughts?

Posted By ICFHybrid on 11 May 2013 01:43 PM

Looked up the Black Jack Roof sealing

Asphalt and mineral spirits to seal seams? Is that considered green?

The Black Jack Ultra Roof 1000 is a white siliconized elastomeric latex.

Posted By kogashuko on 11 May 2013 11:11 AM

Looked up the Black Jack Roof sealing... Is it too thick to put through a sprayer? ... Would a 5/8 hp sprayer do the job with this stuff? Thanks.

According to the Black Jack Ultra Roof 1000 application guide:

RECOMMENDED APPLICATORS:  Roof brush, 3/4" nap roller, or airless spray in 10"-12" pattern, 2000 psi, .021 to .025 spray tip

I would spray it from inside the stud cavity, close up with just a 2-3" wide band in the corners of the stud cavities where the exterior foam meets the studs, bottom plates, and top plates.  Then spray over the joint between the bottom plate and sub-floor unless it was already well sealed with foam or construction adhesive.  One or two beads of polyurethane construction adhesive such as PL Premium on the subfloor before the wall is stood up would be my preference because it provides a strong bond and tends to expand and fill voids as it cures.  But if the wall is already framed, coming back with the elastomeric coating at this joint should air seal it sufficiently.  Then spray the joint between the two top plates.  If you spray the face of any studs or plates, I would come back before it dries and use a thin metal or plastic scrapper to level the surface for drywall and force more of the elastomeric into the joint.

Latex is a pretty meaningless term. I wouldn't assume that anything is safe or green without checking.

I wonder if there is some type of adhesive/binder that in sufficient quantities would turn spray cellulose into an effective sealant/air barrier. Ie, something like spray the cracks with a high adhesive mix and then come back later to fill with a low adhesive damp spray (or use dense pack).

I looked at Knauf Ecoseal which is about $200+ before shipping a bucket and is a mixture of cauk and latex. Downside is that it is about the consistency of a milkshake requiring it to be used with a $3000 sprayer. Once opened the entire 5 galon bucket only has a 60 day lifespan.

I can pickup a galon bucket of this black jack stuff for $19 at lowes before my military discount. If I need more I just drive down and buy it. I will not have gallons sitting around.

As for the green aspect, I am mostly worried about the energy efficency green. Safety is an issue so I will definitly be checking the MSDS for this stuff. If anyone was at all worried about what the stuff did to the environment there would be no use of spray foam. Building codes would also require twice the insulation and exterior rigid foam on all construction.

Make sure you get the elastomeric roof coating with the 10 year warranty, not the 7 year stuff. My local Lowes only carries the 7 year warranty stuff in stock but can order either. The 10 year stuff has silicon added and is much more pliable and fills voids better. I've tried both.

Will do, thanks for the heads up!

I am following your reports here, as I will need to air seal my walls of a home I will be building within the next 6 months. So please let us know what you decide on an how it works out.

Picked up a can of the 10 year stuff at Lowes for under $20. I am on the fence about trying to apply it with a brush or waiting and buying a sprayer. Honestly, I dont know if I will get to it in the next couple of weeks. I will be on vacation the end of next week. In the meantime my time has been filled with stuff I need to do before. I have stuff to do at work coming out of my ears including overtime tomorrow night. The sprayer I am looking at is a cheaper $200 harbor freight paint sprayer 5/8 hp. Since the whole room will be barin when the drywall is done I plan on using it to paint the room too so I will get good use out of it. Anyone, know if the smaller cheaper sprayers will work with this stuff?

I will have a whole 2 story house to do within a year, so really need a cost effective and DIY solution to air seal the interior side of the OSB and studs.

I am interested in what some of the experienced folks on this board have to say about this too. I won't be able to afford spray foam, but I would like to do something before the blown in cellulose is installed.

John R Lee, Polyurethane caulk (for example Tremco Dymonic ) applied with a battery powered caulk gun (I got the Ryobi 18 volt) is very DIY doable and affordable. It provides an excellent seal for an airtight house. I caulked everywhere framing and sheathing met, every nail hole, top and bottom plates, etc. In the few places I could not get the caulk gun in, I used spray foam, and also used the low expanding spray foam around the windows and doors (the kind you get at the big box stores).

My total cost including the caulk gun and battery - $520.

-Rosalinda

Rosalinda, do you recall how many square feet of wall space you had to caulk? I have about 3900 square feet (4 walls, both stories). I ask, because I'm not sure how else you'd calculate your caulking needs. Obviously, the amount of windows alter that calculation somewhat. Did you caulk around the interior of the windows too? Or did you use other means to air seal around windows (Where sheathing and headers meet window frames).

I guess you buy a bunch of caulk and take back what you don't use?

-John