Vapour Barrier in a Van - I can Prove they Work.

[@jazzz60]

A great practical demo on how it works! Genius. Thank you Greg! When I did my insulation I got half the van done with VB then winter came. Half my van was dripping where there was no VB, and the other half even though not sealed at edges was bone dry when I cut into it to check. So doesn’t even have to be 100% sealed to be massively effective. If the air doesn’t move through that gap it can’t carry moisture into it. Obv being sealed helps guarantee this. Front half of van started getting mould spots where water droplets kept collecting on top of PIR boards in ceiling. Vapour barrier for the win! Can’t cheat physics!

[@GregVirgoe]

That’s a brilliant practical example confirmed. Nobody ever backs up their contradictory thoughts with actual proof or science so thank you for another rock solid example

[@mattstockton2433]

So good, thanks. I’ve put a 7mm foil topped adhesive foam directly on the metal then put insulation on top of that. Do I still need a Vapour barrier on the outside of the insulation, eg over the top of the insulation as well? I see some people put a really thin foil over it. Appreciate your thoughts

[@Chris66able]

@@GregVirgoe I can prove it, watch your video. It proves you are wrong AND you don't know the difference between a vapour barrier and a thermal barrier..If you were right then there would be condensation on the outside of the vapour barrier but there isn't because its not as cold because the insulation is acting as a thermal barrier. That side of the bucket would be dry without a vapour barrier. As for other people not posting proof on here that is an infantile, narcissistic comment, most people do not video everything they do unlike you.

[@maxv77]

I was watching a video on this subject from a guy who builds campervans for a living. He didn't put a vapor barrier on. I questioned this. He said most professional van builders don't as it causes more issues later on down the vans life.

[@jordanhanson316]

Better to have some breathability if moisture does get in

[@PixelShade]

Greg, you are an absolute treasure for the RV- and Vanlife community! :D Having videos like this is key for people to understand how these things work.

[@tonyhawk123]

In an ideal world we'd all have a Summon-A-Greg app, which sends a robotic Greg to just do the job for us.

[@GregVirgoe]

I really appreciate that, thank you 🙏🏼

[@rbrown]

Nice demo but there is a problem ! In theory in a tiny test where you can actually fully seal off the area, yes it works. Vans are not fully sealed nor are they meant to be. Manufacturers have many drain holes, plugs, plastic trim attachments that come all way through into the inside of the van cavities. Thats why vans are designed to drain. Then we go and try to fully seal them up. I do partially agree that adding multiple layers of good insulation and having partial sealed barriers on large wall and roof areas is a good idea. BUT you simply can't full seal up all voids and all areas. So what happens when you try ? You end up sealing in any damp and wet that gets behind your vapour barrier, and it will. Best idea is to use some form of final sheet layer of insulation (vapour barrier) to all large surfaces areas, this prevents "most" of your living space warm moist air hitting the walls BUT then add good ventilation so the easiest path for all that moisture is your roof fans, open windows etc. All the areas you can't fully seal, allow the cavities to still breath. On our van I did 90% seal up with a final layer of sheet insulation behind roof and wall panels. But at the edges where roof and ceiling join, at the lower areas especially at the back of van, the cavities can still breath to dry out if need be. our 2 Maxx Air Fans are either open, or open and running pretty much 24/7. IN below zero in winter if were skiing the roof fans are open and Diesel air heater running to flush moisture and dry the air out. A year later and I have pulled wall and ceiling panels and zero condensation issues. Day to day inside the van we never get condensation, just a little on the inside of the windscreen sometimes. But as far as trying to full seal the van with a vapour barrier, from all the research I've seen vans aren't designed nor should they be full sealed up, vans are nor designed by manufacturers to be fully water proof and fully sealed up behind all the cavity spaces. Thats why there are drain holes all along the van sills.

[@shadowfire77]

Problem with this theory is that you might get condensation quickly where you have the steel visible and any water there that tries to espace downwards but get trapped behind the insulation in the walls. Your theory could work if you leave an air gap between the insulation in the walls so the water can follow the steel walls and flow downwards. Also yes the vans are designed to let water out - because they get condensation. If you remove the physical possibility to get condensation, then you won't get any. It's physics laws straight forward. I've built 10 vans now and I'd still say that the best thing you can do is avoid any of the internal air to reach bare metal and the very best method for this is adding Armaflex closest to the steel. Then it's completely impossible to get any condensation at all.

[@renstillmann]

I think this is the way. But you must have an air gap (20mm preferably if using some reflective on foam board) between the steel and insulation. This way the van can get rid of the condensed water like it was designed to. Now I would guess you could easily go for some thin sheep wool between your steel and (actual) insulation. Since it's breathable and mold resistant. It should release any moisture over time. If you go this route I would guess these so called climate vaper barriers are the way to go. They control the flow rate a bit better to keep a nicer climate inside the van? Question mark? (I am no expert, just learning and reading about this topic)

[@Namdor2012]

Wrong, cavities are only in doors with WIND down windows, in every van I know of....No drain holes in my Van apart from front doors, they are designed to release water as water enters from the winding window...Trim Attachments on any van should be sealed especially sidestrips, look at umpteen youtube videos about sealing factory roof plugs, and side trim!!!!Major issue with vans, they need trim properly sealed regardless of insulation or a build out..Do proper research! Not sure what Van you have but it Ain't a Merc, Transit or others I know of..

[@rbrown]

@@Namdor2012 After 1 1/2 years and multiple sub zero ski trips I have pulled down my ceiling and wall panels and pulled back the 2 layers of Thinsulate, and the solid sheet (foil radiant layer) and what did I find ? No sign of any condensation, no water or condensation damage, no mould or mildew. Dry as a bone. I do not have a vapour barrier ! A cavity is just a "space" the whole van behind the walls, ceiling are cavity spaces. I do have strong air barriers and plenty of active ventilation and airflow 2 x Max Air fans open or running 24/7 You don't need a vapour barrier. Allowing a van to breath and plenty of airflow, and good insulation, is the key to stopping condensation. I have seen many a van that tries to seal up everything and they pull back walls etc to find damp, mould, wet insulation.

[@tropicaoptica]

@@rbrown Okay so who is right here?? I want to convert a cargo trailer into a camper 😩

[@LindzandLife]

Thank you Greg this is the way I've done my insulation on my build and so much rubbish about the vapour barrier. I'm about to start electrics and your videos are a blessing 🙌

[@GregVirgoe]

I’m pleased that you followed my method. You will have no problems in the future. Best wishes 😊

[@leebrown9680]

Smug grinning from me as I followed his advice. I can't tell you how many videos I've watched that said you don't need it. Thank you Greg 👍

[@GregVirgoe]

I know I’m trying my best to help point people in the right direction

[@campervibe]

100% agree with you on vapour barriers. Great vid 👍

[@GregVirgoe]

Thank you both 🙏🏼🤩

[@CLdriver1960]

Well done Greg. I’m going to share this video with my van builder friends! Edit: There’s also the effect of increased relative humidity due to cooking, heating and breathing. Good reason for proper ventilation as well. Thanks again for another great van build video. IMHO, you’re one of the best on YT!

[@GregVirgoe]

Thank you very much. Really appreciate your support 👍🏼😃

[@boris_the_crafter2945]

I'm all for vapour barrier and have installed it, the experiment has proved the need for insulation. It would have been interesting to see a 1/3 of the bucket with just insulations 1/3 with vapour barrier 1/3 bare metal. Cheers for the video anyway 👍

[@GregVirgoe]

I’ll do another one just with insulation to show that condensate too 👍🏼😃

[@noiseache7720]

It would be interesting to see behind 'just' vapour barrier too. For those spots where you can't get any insulation. Great vid Greg.

[@AndyMiles-qu4ew]

well done that man, you have done me a 100 % big favour. I have now decided how to insulate and vapour seal my van. Thank you.

[@GregVirgoe]

I’m glad you found that to be useful. Thanks for watching 👍🏼

[@peterbrockman161]

I live in Tasmania and when I commenced my van build I had the luxury of watching your van build videos Greg. Hence my Sprinter has a complete vapour barrier and is well insulated. This demo video just impresses how vital those two components are when well fitted. Thanks mate. 👍

[@GregVirgoe]

I’m very pleased you did the right thing. Well done 👍🏼😃

[@jonnypickett2546]

Nice one Greg. I have followed your advice on 3 van builds after seeing that you obviously know your onions.. I would be interested in seeing the test again using insulation but no vapour barrier as I know many builders put in insulation with no barrier..

[@GregVirgoe]

I will do that as a follow up video. 👍🏼😃

[@craster_van_kippers]

Thats exactly what I thought jonny. Get it done Greg as that will be the one that will get people thinking.

[@riboid]

The building philosophy years ago, was to put polythene (non-permeable) over the insulation (usually Rockwool or fibreglass (itchy stuff) and then plasterboard over it. But, any gaps within the plasterboard, plaster failure (plaster can provide air tightness layers too), the polythene can sweat at the back and the moisture will run/drip down and start the erosion process of your timber studs, so, that's why, if you want increased air tightness within your house, you use an air tightness member called Intell and then tape up the seams/joints with Tescon Vana air tightness tape.

[@stevenbeattie1137]

Thanks for this. Just started building my van and your videos and guides are by far the best. Always good to learn from someone who genuinely knows what they're talking about! 👏👏👏👍

[@GregVirgoe]

Thank you and best wishes for your build.

[@bruceeldred6417]

Thanks for the video!!It would be interesting to see how much moisture would get in if there was a hole in the vapor barrier. It would have to be a long term test. I used the same type of barrier, but when adding finished wall, I know there are some screw holes through the barrier. Hopefully the small amount of moisture that gets through will do no harm.

[@pau1phi11ips]

Screws are usually fine, the screw self-plugs the hole

[@GregVirgoe]

As Paul rightly says a screw does not leave a hole 🕳😃👍🏼

[@laurenmichele2029]

@@GregVirgoe what about light fittings

[@GregVirgoe]

@@laurenmichele2029 you seal around any recesses or cables with foil tape as I have shown in my build videos. A little care and attention is all that’s needed. 😊

[@johnledgard3596]

Great experiment Greg, very clear. I'm eagerly awaiting the next addition with insulation on the bucket but no vapour barrier for the comparison between vapour barrier or no vapour barrier. The time and effort you put into these videos is really appreciated.

[@GregVirgoe]

I might have to put these in a dedicated playlist. 🤔🤩

[@stephenhall4432]

Hi Greg, it was great to finally chat to you in person after following you for nearly 4 years. Hope you had a great Camp Quirky. You will need a rest after meeting so many people. Regards, Steve.

[@GregVirgoe]

It was extremely busy but also great to meet so many new people that follow our channel. Thank you Steve 👍🏼😃

[@0i-di]

Did exactly this on our build thanks to your van build series. Huge thanks! The van is bone dry and stays cool in the sun and warm in the cold. So we’re very happy campers. Cheers Gregg. Would never have known what to do without you 👍🏻

[@GregVirgoe]

That really makes me happy 😊 I know your van will be safe now

[@0i-di]

And I’ve just noticed I spelled Greg with two g’s… face… hand!

[@GregVirgoe]

@@0i-di no problem I’ve had much worse 😂👍🏼

[@neilt]

A really good demonstration. I've noticed a lot of US based van builders don't install vapour barriers, so have wondered how necessary it is. Now I know and will ensure I fit one when I get around to doing a build.

[@GregVirgoe]

The only time you wouldn’t need one is if the climate you was living in was always very warm above the dew point. 👍🏼😃

[@neilt]

@@GregVirgoe That did occur to me as a reasonable situation.

[@richies6898]

Your van build videos are constant source of reference Greg, the difference adding just the PIR board to the roof of the van has been significant which convinced me I was going the right way. There's been a lot of chat around vapour barriers on the forums, this video should convince any doubters. You will spend thousands getting the interior how you want it, and have it all undone in a matter of months by ignoring this. Great work as always Greg 👍🏻

[@GregVirgoe]

Exactly that. Thank you 🙏🏼

[@graudinsedgars]

Great video. I cant see how you can 100% seal your van. It would be interested to see if you would put small hole in, to demonstrate if you put some screw hole in by accident when you are working on your van

[@GregVirgoe]

Firstly screws don’t leave holes unless you take them back out? It’s very easy to seal plastic trim clips, tape joins and edges, tape behind sockets and lights. It’s not hard to do. 👍🏼😊

[@popeyethesailor9]

I totally agree with what you say Greg. I was interested to see what VW did in there California, when I inspected one there was no insulation or vapour barrier behind the sink cupboards and the bare skin of the van was visible, this was on a 2018 California. I did hear that Vw say the output of the diesel heater over comes any issues. When i did my Vw camper I didn’t use any insulation I just rely on the diesel heater, obviously it’s worked much harder and very very wasteful on fuel, but in the morning after a winter camp the exterior of the van like the inside is bone dry. If I used my van for longer than weekends then I would have adopted the vapour barrier and insulation approach. Great video as always.

[@GregVirgoe]

You have to keep the entire metal fabric of your vehicle above the Dew point temperature and provide loads of ventilation too but I guarantee it would cost an absolute fortune every night and would not work over winter when it’s really cold. You are paying ridiculous money for that sub standard installation too 😳

[@Olan...]

That is an absolutley brilliant Demo Greg...i have converted 3 vans in my time and always carry out thermal insulation and vapour barrier as standard. Great video.

[@GregVirgoe]

Then you can sleep peacefully at night knowing you’ve done a first class job 👍🏼😃

[@fboest]

Those kind of proof videos are absolutely brilliant

[@GregVirgoe]

It’s not just someone’s opinion you can see the facts for yourself 👍🏼

[@abikerstale806]

Excellent demonstration of how to form a closed cell installation by using insulation & vapour barrier- I do smile when I see comments about using vapour barrier & the reasons why you shouldn’t use it. Yet they use celotex on there roofs or suggest ventilation- you just need to sit in a back of a van when it’s pouring with rain outside to see the condensation forming like a river… - no amount of ventilation will stop it forming, unless you’re sleeping with all the doors an windows open. Not very stealth or safe! 👍 Thank you for sharing the holy grail of Vapour barrier debates! 🎉🎉

[@GregVirgoe]

Thank you for your support 👍🏼😃

[@Chris66able]

This comment made me laugh out loud, thinking because its got similar properties a bit of celotex is the same as a vapor barrier !!

[@lud1593]

Hi Greg thanks for another great video👍. Just watching a new channel called Ame in a van and she talks about this guy who is an absolute legend who she watched whilst building her van. That guy is you.👍

[@GregVirgoe]

Ame and I chatted a few times when she was building her van 🚐 I’m so pleased she is now living her dreams and enjoying life 😃

[@UKRussellSmith]

Be interesting to see what would happen with just insulation and no vapour barrier. Maybe do the same experiment but hold the insulation on with chicken wire. Great video though Greg as all ways 👍

[@pteppig]

Closed cell foam like armacell might show some condensation when it's not entirely glued to the shell. There could be rust between shell and insulation. But if it's glued on well, it's like a barrier by itself.

[@theageingexplorer9488]

Perfect use of the studio.. I did watch an American video discussing that in dry areas, a vapour barrier is not required..

[@GregVirgoe]

Providing your climate does not fall below the dew point even at night you do not need one correct. Doesn’t it get very cold in desert areas at night?

[@theageingexplorer9488]

@@GregVirgoe I was just highlighting that one might not need it depending on location. I’m convinced European conversions should have one

[@GregVirgoe]

@@theageingexplorer9488 and I was agreeing with you 👍🏼😃

[@mablethebus]

Great video Greg. And great to meet you yesterday and took the time for a chat. 👍

[@GregVirgoe]

Thank you for coming to say hello. It was great to meet you too 😃

[@MrDeanandrachel]

We’re currently looking for a van to do our own van build & your videos will be a constant help throughout our build. Thanks for sharing 👍🏼

[@GregVirgoe]

Best wishes hope everything goes well for you both 😃👍🏼

[@055sos]

Nice work Greg. Good, clear, simple way to get the facts across...Brilliant!

[@GregVirgoe]

Thank you very much

[@hopesfreedom2322]

Love it when you do this stuff Greg, will wait for a moment of peace over the weekend to watch 🙂

[@GregVirgoe]

Thank you and hope you enjoy it 😊

[@AM-pq1rq]

let's say I have been collecting van building video tips for a year or two now and this particular video popped back up inside my mind after seeing somebody apply spray foam to an interior (it looks good) - i recalled "oh but don't forget the vapor barrier") :)

[@GregVirgoe]

Spray foam is a closed cell product so it is its own vapour barrier and would not need further treatment

[@AM-pq1rq]

@@GregVirgoe thanks! Yes, a few days later and I've understood that now

[@mr.skipper4544]

Great experiment I always wanted to know if this theory works, and you proved that it does work " vapor barriers do work when done correctly" Thank You for proving this theory 👍🇺🇸

[@GregVirgoe]

Yes they do work and it why everywhere in industry when you have cold metal surfaces they are insulated and vapour barrier applied to prevent condensation. It’s not hard to do either.

[@eddvanlife7396]

The Legend Of Virgoe continues. Thanx for clever chemistry lab demo.

[@GregVirgoe]

Thank you very much Edd 😃

[@lindamcdonaldcairns9874]

Thanks Greg we have followed your advice and seeing your experiment we are really glad we did. Especially when we go to Scotland in winter!

[@GregVirgoe]

You can sleep soundly knowing you did a great job 👏🥰

[@markthompson2466]

Best video on KZbin on this vital subject....Fabulous

[@GregVirgoe]

Thank you mark 👍🏼😃

[@davidharrower4097]

Another great video Greg. I’m just starting out on our conversion, and taking your advice from your build videos. First one being, insulation and vapour barrier are essential. 👍

[@GregVirgoe]

You will be doing the right thing well done 👍🏼😃

[@clearprop]

You're preaching to the converted here, but I really hope this provides support to those who still doubt the benefits of a vapour barrier. Great to see you at Camp Quirky, I'll be sporting your famous 'Half Hour' t-shirt very soon... 🙂

[@GregVirgoe]

Thank you for your support Dan. Very much appreciated 👍🏼😃

[@janc9611]

I've been trying to get this question answered for ages!!! Thank you!

[@GregVirgoe]

Im so happy to have answers for you 😃

[@philabraham658]

Thanks for that, Good practical demonstration… as you say, attention to detail in the taping is all it takes

[@GregVirgoe]

Yes exactly and it’s not difficult to do just a little time.

[@ianofsjkartwork]

That was a excellent experiment Greg..............definitely worth spending time getting you insulation right on your van first...........stay safe.........thanks for sharing

[@GregVirgoe]

Absolutely. Thank you for your support. 👍🏼😃

[@elaineinnz]

Great experiment. Couldn't remember if I put the reflective barrier or insulation on first - knew I could rely on GregV to provide the correct answer! cheers :D

[@GregVirgoe]

You are welcome Elaine, best wishes with your conversion.

[@williamwarnold6737]

That is amazing, and you have certainly , proofed your point. I have a big issue on a work van , with moisture collecting on the inside roof , and this is because I am running an engine to generate PSI, constantly during the day , in order to do my job. Which will always be done with side and back doors open. I would be grateful if you would list the materials you used.

[@GregVirgoe]

There is a details playlist for the build of my van showing each stage. I used PIR insulation slab for the floor and roof and side panels and I recommend Diall recycled plastic loft insulation for all the awkward areas and stuffing in beams. Seal over everything with double foil bubble wrap as a vapour barrier 👍🏼😃

[@williamwarnold6737]

Thanks for taking the time to reply.👍

[@gonefilming2020]

Thanks, Greg - another great demonstration! Moisture is not your friend. Proper insulation and a sound vapour barrier are as important as a proper ventilation concept to keep the ambient moisture at acceptable levels. This also goes hand in hand with CO2 management to maintain good air quality in your van. Mandatory info for all van builders!

[@GregVirgoe]

Absolutely most important indeed 👍🏼😃

[@wanderingzythophile9083]

May I suggest you do the same experiment, but without the vapor barrier material? Tape up that same insulation material on one side and add the ice/water and show what happens.

[@GregVirgoe]

Yes I will do that to prove that it is only the barrier that is working 👍🏼

[@nagualdesign]

I'd also like to see how just a vapour barrier (with a couple of millimetres of foam backing or the 'bubble wrap' type) without any additional insulation performs. In a small volume, such as a van, I'm wondering whether a thick layer of insulation is particularly pragmatic, considering that you need almost constant airflow. At night the duvet is your main source of insulation.

[@GregVirgoe]

@@nagualdesign I do another with just reflectix to see if it’s enough to stop condensation forming. 🤔

[@bloochoob]

@@GregVirgoe it’s going to be like an episode of Tomorrows World, with all these experiments 🔬🤓

[@stav2421]

agree, would like to see how just a adhesive backed insulation works on its own, like dodomat superliner. this test is proving insulation + vapour barrier.

[@mmwaashumslowww7167]

That was well different Greg and I was impressed with the result.

[@GregVirgoe]

It really does work very well 👌🏼

[@johnb8746]

Most good experiment and explination of the need for vapour barriers. would be need to see the same experiment with out the vb just with the insulation?

[@GregVirgoe]

Yes I will do that for completeness. 😊

[@stevebennett6727]

You need to repeat the experiment with just the insulation and no vapour barrier now Greg. It brings balance to the test then. 👍🏼. By the way I’m a believer in vapour barrier 👌🏽

[@Daryl26543]

Agree. Another test is needed

[@GregVirgoe]

Yes I agree with you. I will also discuss properties of different insulation as some already are a vapour barrier in themselves. Thank you 🙏🏼

[@orfeaus4240]

Hey Greg, your video saved me IMMEASURABLE time researching this topic. Thank you for giving me hours and hours of my life back! One question that maybe you know the answer to: what impact (if any) do side and rear windows have on insulating a van? Is it better to build out a van with no windows from an insulation & vapor barrier perspective, or does it not matter much? I'd expect having thin panes of glass around the van would diminish the effectiveness of the insulation and vapor barriers, but I hope this wouldn't completely nullify the insulation.

[@GregVirgoe]

When you cut windows in those areas have a greater heat loss as they are no thermally efficient like insulation but it doesn’t affect the installed insulation or vapour barrier. Double glassed campervan style windows are thermally better. With single glass you may get a little condensation on the glass but keep the van warm and well ventilated and that will be a minimum. Best wishes.

[@marcinom3414]

Good job. I've seen many videos of people building their camper vans with no vapour barrier and that made me sad. Mold is toxic, rust is a pain in the ass.

[@GregVirgoe]

Exactly, why would you allow it to happen on a daily basis when it’s so easy to prevent altogether 🤔

[@marcinom3414]

@@GregVirgoe Lack of knowledge I guess

[@robertmackintosh5163]

Excellent presentation, explains the situation very well. We have lots of condensation issues here in this part of the world, central Canada.

[@GregVirgoe]

The winter 🥶 does get very cold there

[@stephenevans2195]

Hi Greg I’m just about to start a van motorhome conversion and have just watched your video on vapour barriers! I’m totally on your side. If you get a chance please look on KZbin at a Vanology Conversion video on Not to have Vapour a barrier!!! 16 January 2024 They even leave gaps in the insulation to let the air in? Let us know what you think??

[@geofftaylor368]

Nice one Greg, nice to know all my hard work was worth doing. 😇😍

[@XxXTMillzXxX]

I believe a vapour barrier is vital for a van build in the UK or any cold climates. Even if you make mistakes and leave a few small gaps/holes I believe although condensation will occur it will be far less of a problem compared to no vapour barrier at all.

[@GregVirgoe]

Absolutely correct and spot on 👍🏼😃

[@sherifelsharkawy7041]

You are an absolute genius 🤓. Your videos are all amazing 🤩. I am trying to watch all of them , before I buy my next van for a conversion. Thank you so much for all the efforts and all the valuable information that you introduce into your amazing videos. Honestly, I would trust no one to do the conversion of my next van , but you my friend. Great job 👌👍 I hope you can do it for me 😉

[@GregVirgoe]

I can help give you the right information. I don’t convert vehicles myself for a living. 😊

[@stevehalll-hl9ik]

I have learnt so much from this video and your others. Saw you at Stratford upon Avon doing a talk to the punters. Learnt much there as well. Cheers Greg.😊

[@luappaul21]

I am 100% with you on the importance of the vapour barrier but I was a little perplexed to see you use those stick on steel spike things in your previous roof insulation video for holding the Celotex boards up, because what you've done there is introduce a thermal bridge into your nice efficient insulation. I'd be interested to see you do this experiment above with one of those spikes installed in the middle of your insulation, and see if you get a little spot of condensation around that tophat that sits on the outside of the insulation and the end of the spike. Van's are full of thermal bridges, it would be hard to get rid of all of them, but introducing more seems unnecessary.

[@sammcloughlin9291]

Awesome way to demonstrate the benefits of vapour barriers...

[@ddraigmon6423]

Hi, I am worried about water moisture is in the van panels getting locked in and not circulating out . I have a crafter and they are known to leak from the outside trims . What’s you view on this Greg

[@CoherentChimp]

I don't know why you bother Greg. There are too many dummies who will never believe or accept that they need a vapour barrier. But well done for fighting the good fight even though its a futile exercise.

[@GregVirgoe]

As long as I can help those who are looking for sound advice to make the right choices then I’m happy. Those that choose to ignore facts will have to suffer the consequences. You can lead a horse to water, but you can’t make him drink it. Thank you for your support

[@chrisneville7310]

Great video Gregg👍, I spent over £500 on the insulation and vapour barrier, I'd never put in a single glazed window for that reason also.

[@GregVirgoe]

The double glazed ones are much better thermally. We do get some condensation on our bonded windows when it’s really cold 🥶

[@chrisneville7310]

@@GregVirgoe A great excuse to leave the cold winters behind 😁👍

[@buddysinsight9834]

Hello Greg your comments are turned off in your last video I don’t know if you new that. Ame in a van gave you a really good plug last night :). She converted a transit using your good videos 👍

[@GregVirgoe]

Yes the video is made for children so comments are not allowed 😊

[@candicecwl8186]

This was a great demonstration. Your videos have been so informative.

[@GregVirgoe]

Thank you very much, I’m pleased you like them Candice 😊

[@davopottso1]

I'm 100% convinced now! Nice One Greg!

[@GregVirgoe]

I’m glad it has helped you 👍🏼😃

[@cliffp.8396]

Excellent demonstration, well done Greg.

[@GregVirgoe]

Thank you 🙏🏼

[@orangealpine5267]

Top advice from a well trusted source, Thanks Greg

[@GregVirgoe]

I really appreciate your feedback 🙏🏼😊

[@tanyaroyredcar]

proves that. Good one as ever! Hope that you're both well. R&T NYorks

[@chrism4452]

Such a great video! I’m in the middle of a build and the thought of moisture stopped me In my tracks. Glad to have found you on KZbin! Side note: Have you or anyone dealt with water build up in the rocker panels? I have run into this issue with Ram promaster 2500. I’m lost with how water keeps getting in. 🤷‍♂️ ty for all your effort in each vid!!

[@GregVirgoe]

I’m aware that there is a poor design on the scuttle below the windscreen that allows water to pour onto the engine bay. Make sure any drain holes are not blocked with debris, any rubber bonnet seals are intact. Use a bit of DW40 on head as water repellent. I have known others to cover the engine bay with on combustible plastic sheet to keep water away. Hope some of those help you 👍🏼

[@a_crafty_crafter]

Brilliantly demonstrated. Your videos are great and very informative.. keep up the good work.

[@GregVirgoe]

Thank you very much Ian 👍🏼😃

[@andrewgraham2865]

Really great but simple practical example and explanation - well done Greg!!

[@GregVirgoe]

Thank you very much Andrew 😃

[@Deepthought-42]

I would like to see the same experiment with a small hole in the vapour barrier hat has been unsealed caused in a practical case through passing a cable though the vapour barrier and failing to seal it.

[@ian_morg]

This is why I did my van as you did yours, thanks for the explanation though 😎💪🏼

[@GregVirgoe]

I’m pleased you did the right thing 👍🏼😃

[@brianmcclure8012]

Super and simple experiment Greg!!

[@GregVirgoe]

Glad you liked it 👍🏼

[@brettsheard8847]

Perfectionist. Love your content and van build mate. Wish you and your family well. Happy travels Greg x

[@GregVirgoe]

That’s very kind of you. Thank you 🙏🏼😃

[@blakerichardson414]

You see it a lot in the US with young couples making and selling vans not installing a vapour barrier. It's less than a days work to fully line a van with a vapour barrier.

[@GregVirgoe]

If you plan to only use it in very hot climates it’s not an issue but as you rightly say it’s so easy to do why not fit regardless and have peace of mind.

[@guntherpommer6433]

Thanks Greg for the valuable information you provide. Watching you from far Chile. Cheers mate!

[@GregVirgoe]

Really appreciate your support 👍🏼

[@toronado455]

great experiment and explanation! thank you! this type of information is precisely why I subscribed to your channel in the first place. 😊🏆✅

[@GregVirgoe]

Thank you for your continued support 👍🏼😃

[@MotorcoachTony]

Great video! Thank you for sharing! I'm curious what you or others think about "professional" spray foam insulation. Seems that would seal things pretty tight. Pros? Cons? Thanks!

[@GregVirgoe]

Yes it’s an excellent insulator and will solve all condensation issues. Only cons are can be messy install and cleanup plus it’s a permanent solution and easily removed if needed.

[@jbsmith1]

Excellent demonstration Greg. There's a tough crowd here in the comments, but the physics don't lie. They have two choices, use a vapor barrier or use a dew point meter and always keep the ambient temperature above dew point lol.;)

[@GregVirgoe]

You would have to heat up the steel body of the van to above the dew point to stop it condensing. That’s a lot of heat to use in cold months.

[@GregVirgoe]

If the insulation is permeable and allows moisture through to the metal then that alone won’t work.

[@manondeslauriers2645]

Excellent démonstration!

[@GregVirgoe]

Thank you 🙏🏼

[@Regi869]

Nice one Greg. I'll check out your videos about insulation in your playlist. Thanks

[@GregVirgoe]

Thank you very much. You’ll find some very useful facts there 😃

[@happyglampers9053]

Facts over fiction i’d say Greg. You’re akin to Ronseal … does exactly what it say in the tin👍 PS great to see you imparting your time serves skills at Camp Quirky this last weekend too 👍 Cheers

[@GregVirgoe]

I’m happy to give my time and expertise for free so that everyone can benefit by doing the right thing and not be sidetracked by mis information and speculation.

[@CORRIGEEN71]

Great illustration

[@GregVirgoe]

Thank you 🙏🏼

[@bloochoob]

On the top of my van list, to find and sort out any rust spots, insulate and vapour barrier, a good quality extractor fan, safety security items and methods. After that, I’m quite happy with a basic build, a bed, a bucket and a baseball bat, then I’ll add more home comforts as I go on

[@GregVirgoe]

I’m pleased you got the essentials sorted out. Happy travels 😃

[@bloochoob]

@@GregVirgoe Many thanks to your expert advice videos! 👍🏽

[@fozzledoff1]

Great demonstration.. but would it be possible to include an edit where you just have the wool insulation and not the aluminium wrap?

[@GregVirgoe]

Yes I think I will revisit this one with different insulation build ups 👍🏼😃

[@nectarcape]

When you peel the instulation I can see some small droplets in the bottom part of the can and also on the left side (few small dros). Is that normal? Thanks Greg, you are the superman of insulation!

[@GregVirgoe]

It transferred from the outside of the foil tape that was stuck to the bucket when I ripped it open. It was not condensation inside there

[@Baloovanz]

As always fantastic video Greg. I really do love the scientific approach you take.

[@GregVirgoe]

It’s not just my thoughts it’s actual facts I’m trying to convey so people get the right information 😃

[@Baloovanz]

@@GregVirgoe and what better way to prove it than scientifically controlled experiments? Great job!

[@noelholland9116]

Hi Greg. I’m a very tight budget and I’m thinking rather than spending €200 on silver bubble wrap could I use something as simple as PVC bin bags. Thank you for your very informative videos and looking forward to more. Regards Noel

[@GregVirgoe]

Something stronger like this sheet would work ok and only £25 👍🏼 amzn.to/3SPda2L

[@lincolndave1966able]

Great video Greg, it absolutely highlights the importance of both insulation and a correctly installed vapour barrier. I am at the start of our van conversion and my initial thought is to have our vehicle insulated with closed cell spray foam which has the triple advantage of doing the job of anti rattle, highly effective R value insulation and also a solid impermeable vapor barrier. The cost and speed of spray foam insulation application certainly beats the traditional three stages of rattle sheet, then insulation material of choice and then a vapour barrier, which may not be 100% airtight unless meticulously applied. Many canal boat builders offer spray foam insulation service from around £50 per meter of internal narrowboat length which is roughly the same width and height as most vans. As this subject stirs strong and often conflicting opinions I'm sure i will be slated for mine but your video clearly demonstrates the importance of effective installation and vb application.

[@GregVirgoe]

Spray foam is the very best solution as you say.

[@JensGraikowski]

I've thought about spray foam insulation too, for exactly the reasons you mentioned, Dave. I'm still undecided though. Apart from the fact that there's nobody offering that service on my little island there's the problem that future welding work will be a pig, since you'd have to get rid of the foam first. 🤔

[@pinkrick333]

@@JensGraikowski I had considered spray foam insulation myself but have seen what happens to metal as it expands and contracts.

[@RedBatteryHead]

Nice empirical test. Love those things. Thermal camera would be neat for illustration too.

[@GregVirgoe]

I tried to find a thermometer to check water temp but I think the results speak for themselves. 😃

[@RedBatteryHead]

@@GregVirgoe i was thinking to show the thermal properties. I think you could see with a top view the cold to ambient on the insulation side.

[@GregVirgoe]

@@RedBatteryHead you can see a small bit of conducted cold on the foil tape so there is a little condensation on the outside of the tape near the bucket. Proving that just a vapour barrier against the steel would not be enough. You need the insulation as well to raise the surface temp of the vapour barrier so you don’t get condensation on the outside of it.

[@ConiferTree909]

So glad I came across you videos Greg! I've done a tonne of research on this subject and, yes I'd like to install a vapour barrier. I've decided to use a decent quality polythene tarp instead of reflectics as I'm converting a Ford Connect; much smaller build. So I don't have the space to use, giving the reflectic it's 1/2 inch air gap, y'know? I did have one question though: How have you mounted things/ furniture onto the van wall? If you can't make holes in the wall / through the vapour barrier how do you stop things from sliding about in the van? Or how do you seal the holes?

[@mitsibeaver]

Nice experiment and great to see the results and put my mind at rest with my sound deadening. Might have to get a roll of foil tape just to make sure those edges are totally sealed. Cheers 👍😎🤟

[@GregVirgoe]

Yes you must tape all the edges and joins or it will not keep the moisture out. 👍🏼😃

[@mitsibeaver]

@@GregVirgoe Ok, the metal foil tape will be suitable, yeah?

[@GregVirgoe]

@@mitsibeaver yrs aluminium foil tape is the best thing to use. 👍🏼

[@shaungooch1244]

Another amazing video. Simple experiment to show Proof of concept. You should have been a teacher

[@GregVirgoe]

I’m glad you liked it and thank you for great feedback too 👍🏼😃

[@GoodieJoy-hh9uc]

Thank you Greg for this example, but what happens to the van in a heatwave, can this vapor barrier prevent the van becoming an “oven”?

[@gert-jantenpierick6358]

Super series on building a camper van Greg! Really enjoy it. About to start isolating my Ducato with PIR isolation and Armaflex. The question I still have is when we use PIR isolation on the walls and the roof/floor there will always be an air gap between the steel and the isolation in opposite where Armaflex will leave no air gaps. Will there be condensation between the isolation and the steel? On one hand I think no, because the temperature on both sides of the steel is approx equally. Am I right? We will make mistakes on our first van build but would prevent one with isolation. Looking forward to your response.

[@strifex-suspension-works]

I'm wondering, what is your view on the topic of penetrations in the vapor barrier, for example, where LED, sockets, etc. pass through it? Surely, these types of "penetrations" cannot be fully isolated by a vapor barrier and thus vapor will get through them.

[@jimmcgarvie1483]

Nice work Greg 👍

[@GregVirgoe]

Thank you 🙏🏼

[@carloknuwer1026]

HI Greg, ive seen almost every single video of you and used as much of your knowledge as my build would allow. Still everyday gratefull of that, Thank you very much. Still hate the jubileeclips just like you, started to leak just like yours... And so on and so on... A friend of mine still believes they old sheeps wool thing with cladding... I'll sinds him this video ;-) Greetings from Vught, the Netherlands

[@GregVirgoe]

I have noticed recently that even the manufacturers website for sheep wool insulation are advocating the use of vapour barrier so they must have changed their minds 😃

[@hansbrinker943]

Very nice experiment Greg.

[@GregVirgoe]

Thank you 😊

[@rocket2max]

Thanks Gregg. A Great demonstration. Do you have a plan for further practical demonstrations like using Insulation only without the vapour barrier ? This is a common alternate I hear about. Thanks again.

[@GregVirgoe]

Yes I will do a follow up video to this as lots have asked for that 😊