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Lane Hogstad Posted: Mar 17, 2012 03:47 PM	House wrap or not What is everyone's opinion on house wrap on a steel building. Easy to change panel. Will it trap water? Our problem or not? What are the opinions of the gods.
steven argus Posted: Mar 18, 2012 11:13 PM	We spray a lot of metal bldgs in our area. I reccomend installing house wrap. This eliminates the posibility of warping the steel. Like you said, makes changing the panels easy. Its quick and relativly cheap to install. (labor wise) House wrap (Tyvek) is a very permiable material, meaning that it will allow water vapor (moisture in a gas form) to pass through it. Its main pourpose in life is a seconary weather barrier, meaning it will shed water that gets past the siding. Most people believe it to be an "air barrier". Well, maybe, but its held up with 1000's of staples. It has quite a few seams that are never taped... ever. (the tape is way $$$) If you read the fine print on Tyvek, its only UV stable for 30 days. After that it starts to break down. (round here its considered "siding") Long story short, have the builder install it. Quicker and cheaper than sheathing. Will not trap water vapor which turns into moisture. No warped metal. Sorry for the Tyvek rant. I hate when people say, "we dont need foam, our building is sealed up tight with Tyvek!" I actually watched a new building w/ tyvek on it in a windy day. You could see the wind presureizing the space between the untaped paper and sheathing. It literally pushed the air into every crack in the building. "I don't need foam"... really?
mark moyer Posted: Mar 21, 2012 01:51 AM	if the foam isnt "stuck" to the substrate,,, why bother paying for the upgrade to foam... you have lost any real advantage to a spf system..ie: no next available airspace for condensation to lay out on if there is any breaks in the system..ie the foam to sheathing interface..enter tyvec/paper and you got that interface,,exactly where you dont want it,,, most buckleing is cellular collapse of unstable closed cell resin as provided by the manufacturer...it is pullin the metal as the foam cell structure fails,,,they will always tell you it is an applicator error,,,their pockets are way deeper than yours,,,they will win,,the applictor does not matter..product stewardship in the end does not matter,,it is all about the almighty buck,,much like shrinking aminoplast injection foams,,, but im just sayin,,,
Caleb DeFord Posted: Mar 21, 2012 05:31 PM	Thanks for the explanation of why metal buckles after the foam cures, foamdude. That's the best explanation I've ever heard. Obviously, putting too much foam on at once and frying the foam reduces it's dimensional strength possibly causing warped metal, but I hadn't heard of the "bad resin" reason. That's helpful. As for condensation on the substrate due to a pocket of under-depth foam: condensation will happen whether there is tyvek there or not. I'm not seeing any greater risk from condensation on a substrate because there's house wrap on it. And some metal building owners have wild forklift drivers. For them, replacing metal panels is a real and ominous possibility, and they don't like the idea of having to tear off the inside and outside of a wall just to replace a piece of metal on the outside. If you spray to tevek instead of metal you lose some of the strength that closed cell foam gives when it's adhered to the exterior sheathing, but there's no significant loss when it comes to insulating efficiency and air/vapor control. As far as the foam goes, you get a better yeild spraying on a flat substrate (paper) than a corrugated one (metal.) Personally, I prefer spraying to the metal for the extra strength and sound deadening, but I can understand the viewpoint of my customers who are concerned about replacing panels in the future. Just be aware that you are going to have hot air between the tyvek and the metal while you are spraying and if you probe it and poke through the bulged out paper to the metal beneath, you may get a false depth reading, especially if the paper ain't tight. Just make sure they don't use plastic instead of paper, plastic is an awful substrate to work with. -Foamilyman
Lane Hogstad Posted: Mar 21, 2012 09:05 PM	I don't like spraying on house wrap. We have had alot of requests lately. I think another better idea for a problem that isn't a problem. I had another today that wants titanium roofing paper sprayed on the underside of the roof. Anyone try that? I love the reinvention of the wheel on my liability. Scared of hail. Going to test spray tomorrow oh boy. Reminds me of the old what if my roof leaks. Call a roofer not an insulatin company.
mark moyer Posted: Mar 21, 2012 11:31 PM	caleb..respectfully,,re: sonny boy..you are wrong about condensation and vapor transmission..pure and simple,,re read,,pay attention to next available condensing air space.. the tyvec craze is because we have had a multitude of buckled buildings here in the midwest due to a large batch of bad closed cell resin by a major manufacturer..i know of one applicator who had this product buckle a block wall..but they always end up with an engineer who will sign off saying it is us the applictator who caused the buckleing,,and they have much deeper pockets,,and the customer just wants closure,,so...applicator error it is.. if it was my building and i wanted tyvec tween the insulation,,i'd fitlerglass bag it..save the money..put in radiant floor heat instead maybe.. foam expands,,,pushes,,oil cans buildings,, OK then...cellular collapse,,,buckles buildings,,wrinkles metal panels,,foam shrinks & pulls metal to deformity,, big friggin difference...got pix of both,,,not perty,,not cheap to remediate,, and there ya go...they want us to apply to substrates we shouldnt,,,know we shouldnt,,and then "stand by" the work with warranty and good workmanship when we dont know how its gonna go in the first place,,, lane,,get it in your contract...cover your azz.. you are adding insulation,,not a waterproofin membrane,,
Lane Hogstad Posted: Mar 22, 2012 07:09 AM	This guy is scared of changing the steel in 30 years. I want a good substrate. In 30 years call a roofer. I think the wheel works very well the way it is.
mark moyer Posted: Mar 22, 2012 10:06 PM	..tell him they frequently resheath over the old tin,,,,with foam strips for capillary drainage plain,,and tin over on the exterior..kinda like how they can fix buckled buildings if you have a customer that aint friggin boo coo about schtuff..lol..
Rodney Schares Posted: Mar 23, 2012 07:10 PM	Dude,are you thinking of the same company I am ? BASF and bad resin?
mark moyer Posted: Mar 24, 2012 07:15 AM	actung baby,,, you said it,,, this business is about relationships,,is it not??? and while were in the rumor mill,,, oh and i hear they dropped from our proffessional organization ,,,just take what you want and leave the rest,,, but they should never have taken the very best.. the nite they drove old spray foam down,, and the glassers was singing they went,,, ....what shall it profit a man,,, and did i say???? you know the tag dont you??? (could be wing-tips) and damnit schares,,,small "d"..you know better,, lol
Caleb DeFord Posted: Mar 28, 2012 12:26 PM	Sorry to be so late to get back to this, but I'm not seeing the sense in your house wrap statements 'dude. Are you worried about condensation between the paper and the metal? Is there a concern about water on the metal in the morning if it's just going to evaporate in the afternoon? It's better to have the foam adhered to the metal, I agree, but it's not gonna kill anybody to have house wrap instead. What's the story on the warped metal buildings? Did they do a tear out the foam and replace deal, or did they just put steel over the top like you said? -Foamilyman
mark moyer Posted: Mar 28, 2012 10:59 PM	trapped water,,not to good,, no drainage plain (boss da plane) "but its not gonna hurt.." your liability down the road,,not mine.. condensation frrom dew on the exterior of a building and condensation from moisture vapor diffusion on the interior of a building are 2 different monsters young man...(i luv doing that caleb),,, and yes,,in my opinion it is gonna kill ya,,so there..
richard sucher II Posted: Mar 30, 2012 08:51 AM	In our case, Owner did nothing with the $20K that we had to pay. Bad enough to get us for settlement but not bad enough to fix. Building was in ag setting - combo shop with attached living quarters. Warping only really noticeable in the morning with frost/sunlight. The option to scrap the foam made no sense as skin was still warped. Least expensive way to remedy was to apply new metal skin over existing. "Take the money and run". Many of these buildings metal skins are getting to have lighter gauge metal. Cover your bases for any eventuality or just spray open cell.
mark moyer Posted: Sep 14, 2012 06:18 AM	...revisiting this topic,,,season is upon us here in the cornfield,, i continue to refrain from applying to building wrap under the metal...but man am i seein a bunch of it and getting calls for it,,and they are getting it done by the new breed of foamers makein their way anyways they can... so when the sheathin rusts 10 years from now and these guys are back into lawn care,,frameing,,drywall,,truck driving or whatever it is they really do for a living(and not real well or they wouldnt be tryin to spray foam,,god bless) and the foam rig is long gone,,,who gets beat up for the "product failure"???you know its gonna be the "foams fault" cause its the new thing in the system,,the metal aint new,,the tyvek aint new,,the framin members aint new,,but that foam stuff,,,yeah thats what did it,, anyone run a wufi or ham on this system???lol for condensation potential???whodat??
mark moyer Posted: Sep 16, 2012 07:48 AM	ok,,, so lets try it this way.. do you or dont you??? and why...
mark moyer Posted: Sep 16, 2012 07:48 AM	ok,,, so lets try it this way.. do you or dont you??? and why...
Loren Edwards Posted: Nov 22, 2012 07:18 PM	I'm new to the business we are doing mostly metal buildings so this topic has me worried. I wasn't aware of the warping the metal issue. I like the structural strength the CC gives so direct contact to the substrate is needed for that. How is the house wrap attached to the building it seems like it would need to be put on before the metal is installed to stay in place. How are you guys attaching it after the building is up? Are you just cutting it to fit the section and then holding it in place with tape. If so I assume you are leaving a few inches around the edge so that the foam can adhere to the metal substrate and c perlin like a fillet joint which will hold the wrap in place once cured. This would also give a smoother surface to spray for a smoother look. I am not aware of any companies in my area doing this. Everyone just sprays straight to the metal. There is an over whelming source of foam suppliers out there. How do you find out which ones are causing the warping problems. This is a big concern to me.
Lane Hogstad Posted: Nov 22, 2012 07:57 PM	So lets update. The original building had 2 inches of eps foam cut and installed between the perlins in case the roof ever had to be changed. Owners idea trust me he should know better. Then the new guy in town that had never sprayed foam installed over 20 sets of open cell 10 sets would have been 7 + inches. They have been back to fix condensation dripping from the ceiling. When you look up all you see is voids everywhere. On a frosty morning the heat loss is very evident. The finished ceiling is painted black and left exposed. No coating no rock just black mountainous foam. Did i mention this was a lumber yard. Yes I spoke with them when I bid about covering it and to meet with the building inspector.
Lane Hogstad Posted: Nov 22, 2012 08:19 PM	So did i mention the big G sold the foam to the lumber yard with guidance and knowledge and all the tech support a rookie could ever need. An e-20 gas compressor and gas generator in a 14 ft trailer is all the equipment needed. This ain't cellulose boys
mark moyer Posted: Nov 23, 2012 06:10 AM	lane,,dont be a ******,,accountability... the big G??? ahh tell me who are you??? for the world to see..we are paying for it by the pound and the stroke of our arm... west texas,,welcome to paradise,,, dont worry your little head...shoot away,,the problems with spray foam dont worry the manufacturer,,they just turn their pretty heads and walk away,,be a good business man and have good insurance with a good company that you think wont drop you with the first "bizarro" claim,,and to them most spray foam claims are "bizzaro"....your supplier will never accept responsibility,,they may renumerate or recompinsate but that is for relationships...not responsibility.... we are not the ones applying the house wrap... it is applied on the outside of the building like a wrap,,,then the metal skin is applied... it is the building manufacturers answer to "what if we have to change a panel some time down the road with that foam stuck to the metal???huh,,,yeah??like what if?????" they dont seem to understand "you remove the fasteners...peel off the panel(yes it will take some force)and reapply the new panel,,,then call me to repair any foam that came with the defective panel removal or repair with a froth pak if limited area(it will be...the sky aint fallin)..ask the dealer how many buildings he's sold in 10 years,,,then ask him how many times hes gone to those buildings to replace panels...hmmmm the sky is indeed falling mr little... now wst tx,,we do not apply to house wrap ever... plenty of new applicator,,with no training btw.. getting their foam from the big name companies so they can say that selling against me,,btw...godbless..who will do this application for these farmers looking for cheap... they could give a ratzazz that they have now just created the next condensensing airspace between the metal and the housewrap should any moisture/moisture vapor find its way there...remember there is no perfect vapor retarding system,,and oh god,,lets not forget about all those overlapping seams....and then you have the application itself..newbee..mr-cheap-earl-farmer(give me an 1 or so..that otta do it yeah thats the ticket) physics???who dat??? burp,,turkey,,lamb and green bean casserole...happy thanksgiving belated btw... spray to the metal,,, establish a relationship with good supplier with a rep who is available to you and provides you good tech support or access to,, support you proffessional trade association...they are growing and changing,,but in the end,,it is about you.. be the best that you can be,,in spf,,like yo momma said,,if you have to ask "should i???" you probably shouldn't... finally got cold up here and we launched the h40 rig for the winter,,boyz luv it,,,
Loren Edwards Posted: Nov 24, 2012 10:07 AM	Thanks for the replies. We have a rather mild climate here. Its hot in the summer and moderate winters and very little rain and humidity levels stay pretty low 15-20 percent for most of the year. 1" seems to be a reasonable application rate for this area. These buildings are not conditioned spaces mostly work shops. We paid good money to have a trainer come down and work with us on jobs for 3 days. He wasn't a foam guy so it was not money well spent. He has though been very supportive with parts and even loaned us his personal guns for a few week. My business partner has been to 2 manufacture foam schools. We are both from professional backgrounds and we have no interest in doing shoddy work or being the cheapest guy on the block. We are interested in getting the best training we can so that we can provide a good product for the customer.
mason Posted: Nov 27, 2012 08:42 AM	My speciality, onsite education and training, customized for your company's specific needs. see my website, masonknowles.com Sorry for the commercial, but westtexas was asking. Check with SPFA, ICAA and others for my credentials.