When i was considered a bus nut. I reviewed several builds with SPF and then grinding or knifing off the excesses before applying the paneling. Warped panels at that time came from people blocking off the windows with steel or aluminumand the heat would cuase the panels to deform. I'm trying to determine if I can use SPF on my 5th wheel once I remove the outer skin as ,y 1995 Holiday Rambler uses alumi,um aide panels. I would need to drill each rivet to pull the panel which is a huge amount of work. My goal is to increase usage for 4 seasons and reduce heating and cooling costs while keeping a better environment. I would remove the 1 1/2" of fiberglass insulation and spray with SPF. To reduce thermal bridging I'm thinking about adding 1/8" vinyl strips to the aluminum rib before putting the panel back up. Maybe even epoxy the vinyl to the rib before drilling the rivet hole then apply a small amount of spf to each hole or do it before applying the vinyl. I say vinyl but thinking teflon or some type of material that prevents an aluminum to aluminum contact. Once the vinyl is installed then knife or grind the SPF flush then put up the panel. In some of the coach conversion videos I've seen, a very long knife blade is used on a sawsall to cut the foam for a flat surface. Just worried about creating a compartment so air tight that it would increase moisture and cause mold or rot. The entire RV is built with aluminum tubing and no wood except the interior paneling so the structure wouldn't be affected and a magic fan to control temps might be enough to remove extra moisture. Need to do a roof repair so my dream is to apply SPF on top, sides and under the floor. Maybe open cell on the bottom of the subfloor would be best inase there's a leak and the air could move to get ride of moisture. But your comment gave me another source to review as I had forgotten bus conversion. It was on my mind a lot and then I took a job driving MCI 7,8, 9 and 102A coaches (mainly Ventura-Vegas) and the maintenance I did to keep them operational while driving made me rethink going that route and I wound up just getting a used 37' 5th wheel. Poor maintenance was of course the problem. But after retiring from the military I returned to the theater and not home much. Still working overseas, a diesel sitting that long isn't good but I still enjoy seeing what people did with an old coach. Vegas Bus Nut convention around 1999 or 2000 was awesome. Loved seeing what people did.

Kevin, can you provide a recommendation for a specific brand and product you'd use on a class A with interior walls currently removed?

I worked in the rv capital of the world in Elkhart, IN, from 97 until 2016, and many companies tried using it and it was no good. It was more problems than good.

​@fwdsrq I worked in the RV capital of the world Elkhart, IN, for many years and we ran countless tests, and it never passed testing. Use something else.

Where can we see some photos or video of the wattage? Nobody ever seems to have any.

Photos of warping, please? Really would be helpful to make a judgement for my van.

@@saraheasongis2376 It’s hard to see in a picture now that I’ve fixed it. If you decide to do it tape off where the ribs meet the skin so the foam can’t get in between. Do sections then wait and see how it’s reacting rather than do the whole van and then find out you have a problem.

I pay some good money to see you spray 1-2 mm of foam 👍🥰

I have also have this same question. I'm sure Advanced RV has a good reason for using thinsulate instead of polyiso or xps rigid panels. I would be grateful and very curious to know what that reason is. Advanced RV?

This is a very good question. As I understand the problem is caused by the spray foam contracting as it dry's, as the metal is relatively thin and long this causes it to pull together. This is known in the roofing industry as oil canning. I think your idea may work. The foil top of most sound deadening should take the contraction. Maybe some one will test your theory out.

You are right to question what they say because they contradict themselves and won’t even assert that you must have a vapor barrier with wool to prevent condensation. Out of fear they will offend a customer. When a PHd is that wishy washy why have them on staff?

This is exactly what I think should be done 1st coat then a final.

@@GOLDVIOLINbowofdeath Vapor barriers can often be ineffective because you need a 100% sealed interior for them to work. Most van conversions won’t achieve this so a 100% barrier then just traps condensation and can increase the risk of mould. Far Out Rides had a great explanation of this based off of research Boeing did on insulation and moisture issues in their planes. Their overall findings emphasized that breathability is better, so a vapour barrier over 50-75% of insulated areas is fine but 100% can cause problems.

that is a theory that I would be testing out on my 2019 Ford transit high roof extended

Have you been drinking the Humble Road kool-aid? Never get engineering advice from a retired watch photographer. When there’s an electrical fire in one of Humble Road’s builds the fire will spread like wildfire due to his design paranoia about leaks and mold. If a van builder never brings up the subject of how you get out of the van quickly if there’s a fire, and I have yet to hear this discussed, you should be very suspect of everything they do or don’t do related to fire suppression. Most of these builds actually block the inside door handle to the rear doors with a bed structure right up against them. There have been so many tragic building fires where hundreds of people died because of blocked or locked fire exits. You should consider your rear doors on your van as one of several fire exits. Recently five people in a wedding party limo died in SF Bay Area in a fire because they couldn’t get the rear limo doors open. Imagine what panic it’s going to be like when you wake up disoriented from a deep sleep in a Smoke-filled van after the smoke detector goes off.

It causes big issues over time. I worked in the rv capital of the world Elkhart from 97 until 2018, and the explorer van conversion companies i worked in for a yr. There is a reason it didn't pass for use in these but for unbellys. Over time it gets moisture build up causing rust and the list rolls on.

Thanks for the question LJ. You might find our "What We Know (and don't know) About Insulation" video helpful. There we talk about the insulation materials we do use.

I have a 2005 van so not worried about a little bit of warp, and will get it installed by the company selling it. I'm a bit worried now though about stories of people saying for hot weather it can be harder to cool the van down if it's heavily insulated. Although with 2 vent fans maybe it's ok. Not worried about cold though as winter in Australia isn't bad and I have a diesel heater.

@@matt.163 Spray foam is a great insulator for hot or cold. But it doesn't have high "thermal capacity" meaning it wont store heat within itself. In the summer all you need to do is give the can a good airing out. The things in your van with higher heat capacity such as furniture, appliances, water jugs etc. etc is where the heat is stored & doesn't change with the type of insulation you choose.

Thank you for the question. Many of our clients forego solar because their lithium batteries + aux alternator are enough to keep them off grid during their trips. We still install panels for clients who foresee solar being more useful.

@@AdvancedRV ahh that makes perfect sense. Love how you at Adanced RV put so much thought into your designs and products, so always great to hear from the professionals on why you fit out the way you do :)

What kind of acoustic dampening foam are you referring to?

@@GOLDVIOLINbowofdeath I assume Dodo mat or similar, however I was hoping to use spray foam for the best insulating properties with the added benefit that it would sound deaden as well saving money in that regards. Unsure what to doooo

What about using a spray rubber to seal the inner skin then using spray foam for the insulation!

Why not?

Not sure why I said I wouldn't be using it. But maybe because it crumbles. And more difficult to work with. The thinsulate comes in different thickness and in a roll. I believe it can have a reflective side on it.

It doesn’t crumble, it’s semi rigid avail in 1-6 2x4 panels with foil facing. It’s used in acoustical panels cause it’s one of the best insulation for sound and thermal properties

What kind of rubber gaurd?

Guard

@@saraheasongis2376 Gravel Guard Black Rocker Panel Coating Dominion Sure Seal SVG124...Brand names don't really matter

I was thinking the same thing! So first a rubber spray against the inner bare/clean metal skin, making sure to cover every single surface of metal 100%, then use spray foam to fill in everything for insulation! Someone let me know if that that would be a good strategy! I know it's probably more expensive, but maybe it's the best way for water vapor sealing! Also I heard the some vehicles have drain holes on the inside skins to allow for drying of the inside metal. If I did a 100% rubber inner skin seal, I might cover the drain holes??

@@TheForwardThinker So at the bottom picture two 8 foot "tubes" AKA The rocker panels These are more to do with exterior cosmetics that use The have drain holes Because water does drip down from windows And condensation This also carries the dirt / road salt And is one of the famous rust spots because mud takes longer to dry Thus soft paint And rust Don't Foam in there Rather foam on the inside of the van from it I I

Did you not get their multiple audio and graphic references to the video on insulation this one is in reply to or are you just shamelessly plugging Havelock wool?

@@GOLDVIOLINbowofdeath explain

Matthew Marbaker I'm living in mine while converting it.

@@TimFuller haven't found a hybrid van large enough

The Zenith Promaster is electric 🤷‍♀️

I have a scamp.good question.i would assume it would only warp if the foam was between 2 skins

Please let me know if you do spray it

I think the issue is the relatively high LOCAL temps that are generated as the foam is applied. That will cause the surrounding cooler metal to deform. Also, It will melt any poly film that is inserted. Using oil or wax is counterproductive because the foam needs adhere to the surface and you still have the melting issue. Good ideas, but they break down on closer analysis. The joys of engineering :-/

jaminthomas I’ve used spray foam to make custom seats and it didn’t melt the bin-bags I used. Even if it did, there are heat resistant films that could be used and the adhesion wouldn’t be a problem if there were a couple of spots left uncovered to let it stick to.

@@amymalimichi377 If it were the cost you can be sure that ARV would never tell you “we decided not to use something because it was more expensive”. I’ve certainly never seen them say that he said not to use something because it was more expensive

@@colleenkaralee2280 It's a speciality item. It is generally installed in older homes where they pump it in from teh outside so that it pushes any existing insulation inward. I would start here. www.hunker.com/13415694/non-expanding-foam-types

Exactly, it is the trapped air that provides the insulation.

D LG It is actually paper thin.

I have worked in construction and with expanding foam. One has to be really careful when applying it. I have seen door and window frames warping so much that the windows/doors were not opening the next day after installation.

@@tsalesto It's surprising there isn't some kind of spray foam that doesn't expand so aggressively.

@@MisterFuturtastic there is

@@MisterFuturtastic Every lumber yard and big box home improvement store carries low-expansion foam specifically labelled and marketed for sealing around window and door frames.

It takes a trained eye to see the deformation, you have to see it from the right angle, also noticeable on larger vans.

@@peterbeyer5755 oh come on now LOL that's a bit of a stretch. so we mere mortals wouldn't be able to tell if there was damage haha

@@daratatum6111 I agree, if it takes a trained eye to see it then I'm not terribly worried. Especially as mine is a 2007 model that's getting old.

Someone paying 100k+ for a van might be picky.

I’m sure the price goes thru the roof anyway because they have to remove everything on the inside where the damage is. You can always remove all of that stuff yourself and save lots of money If you don’t have insurance paying for it.

Where did you see the photos? A wrong mix can definitely cause the foam to shrink and crack, but they said they had a foam rep in to try several things, and I'd assume that person would know what they were doing.

Where are you?

@@saraheasongis2376 Il/Wi border south beloit

Fiberglass batts aren't a good choice because they absorb water like a sponge. Then the wet batts sag and compress under their own weight, resulting in the loss of most of the insulative value. Worse, when the weather is warm enough, mold will quickly grow on wet fiberglass batts. I'd stick with a hygrophobic insulation like mineral wool or Thinsulate.