Replacing the fibreglass insulation on my Westy - any tips?

Post by **irishkeet** » 17 Sep 2007, 07:45

Hi

Im planning on replacing all the old fibreglass insulation this winter.
Ive read that the old fibreglass stuff attracts and retains moisture hence the increase in rusting.

My van is in good nick, some seam rust on the cooker side only. All furniture, cooker etc is coming out and Ive decided to reinsulate at the same time.

Im thinking of using polystyrene, seems cheap from wickes

http://tinyurl.com/3xpzqm

I was wondering if anyone else has done theirs in the past or if there is a better option than polystyrene.

kind regards
irishkeet

Post by **High Peaker** » 17 Sep 2007, 10:05

You are right the old fibreglass stuff is like a sponge, holding water against your nice panels. For the same reason avoid high tech thin home insulations like ISO Triflex, as these have fibrous layers which would hold water (oh, and it would cost several hundred quid to do the van).
The best solution is Kingspan or equivalent, which is a closed cell insulation like polystyrene, but this is expensive, very thick, and hard to get into small spaces.
The most convenient is the foil covered bubble wrapp, also available from DIY stores. It is very thin and flexible, so easy to tape into tighter panels, ensuring there is no gap around the edges. Different types normally give their effectiveness as an equivalent thickness of polystyrene, so you can easily compare.

Post by **v-lux** » 17 Sep 2007, 10:19

Different types normally give their effectiveness as an equivalent thickness of polystyrene, so you can easily compare.

Although the installation guidelines need to be taken into account with this.
Usually the silver bubble wrap type stuff needs to be installed with a minimum air-gap to be at full effectiveness.

Also worth considering that should you have any air-gap between insulation and wall panels, then this provides the perfect place for condensation to take place. ie, less airspace = less condensation.

I went for using good ol cheap rock wool style insulation, but bagged it all up in thick polythene bags before installing it in the van. Then added a vapour barrier (thick polythene sheeting and then a layer of the bubble wrap type stuff.

Snug as a bug n a rug

Post by **irishkeet** » 17 Sep 2007, 10:44

wow
a lot to think about
may do the poly (as i have some) & therma wrap too

ill be cleaning up those little white balls for weeks
lol

Post by **syncroand101** » 17 Sep 2007, 11:06

I have been doing the same with mine. Starting with the panels behind the Kitchen unit, the insualtion was so wet when I got the van that it was like a full sponge.

Removed that piece og interior and cut out any rust, treated it, then soaked in Waxoyl.

I then used (click on pic):

[img:200:200]http://www.screwfix.com/sfd/i/cat/63/p4754663_l.jpg[/img]

I fitted 2-3 layers of this, its non absorbant, and light. Did the same with the sliding door, plenty of Waxoyl etc. Now it shuts with a thud - which is strangely pleasing.

I like the idea of using Noisekiller, as in your other thread - then adding this on top...

Post by **v-lux** » 17 Sep 2007, 11:26

Its possible that Thermawrap from B&Q might be better value than that!

Im sure that i paid around £30 for a roll of thermawrap, but it was 1000mm x 7m.
Rather than the 600mm x 7.5m of the screwfix stuff.
Is the screw fix stuff silver on both sides too?

Im really pleased with the results in my van, my doors and tailgate etc also now have a very satisfying thump when they shut (the doors would be perfect if the window mechanisms didnt rattle).

Not tested it for cold yet, but in the excess of 40 degrees in spain and portugal this summer we didnt once wake up feeling like we were boiling in the bag as it were, even in direct sunlight.

well chuffed!

Post by **irishkeet** » 17 Sep 2007, 11:49

Sounds good
I bought sound dampening self adhesive mats which ill put in the cab & doors this weekend, i want that solid thump when they close too (instead of boing!)

will checkout Thermawrap and addd this too

what sort of waxoyl did you use inside the panel, was it the spray one?

thanks
keet

syncroand101 wrote:I have been doing the same with mine. Starting with the panels behind the Kitchen unit, the insualtion was so wet when I got the van that it was like a full sponge.

Removed that piece og interior and cut out any rust, treated it, then soaked in Waxoyl.

I then used (click on pic):

[img:200:200]http://www.screwfix.com/sfd/i/cat/63/p4754663_l.jpg[/img]

I fitted 2-3 layers of this, its non absorbant, and light. Did the same with the sliding door, plenty of Waxoyl etc. Now it shuts with a thud - which is strangely pleasing.

I like the idea of using Noisekiller, as in your other thread - then adding this on top...

Post by **irishkeet** » 17 Sep 2007, 11:53

Hi v-lux

with the Thermawrap how did you attach it inside the panels? I was thinking double sided sticky but it may collapse over time

Also do you need special tape to stick it together I know they do a therma wrap tape

thanks
keet

v-lux wrote:Its possible that Thermawrap from B&Q might be better value than that!

Im sure that i paid around £30 for a roll of thermawrap, but it was 1000mm x 7m.
Rather than the 600mm x 7.5m of the screwfix stuff.
Is the screw fix stuff silver on both sides too?

Im really pleased with the results in my van, my doors and tailgate etc also now have a very satisfying thump when they shut (the doors would be perfect if the window mechanisms didnt rattle).

Not tested it for cold yet, but in the excess of 40 degrees in spain and portugal this summer we didnt once wake up feeling like we were boiling in the bag as it were, even in direct sunlight.

well chuffed!

Post by **v-lux** » 18 Sep 2007, 08:43

I used a silver foil tape to stick the Thermawrap together.

Picked it up from my local army surplus, but i would imagine that you should be able to buy it from most DIY places.

The waxoyl you want is the spray stuff. Worth getting big tin and as syncroand101 says, sort out any rust and soak it in the stuff.

I also did this, stinks for a while, but its good knowing theres at least 'some' protection behind those panels.

Post by **syncroand101** » 18 Sep 2007, 08:49

v-lux wrote:The waxoyl you want is the spray stuff. Worth getting big tin and as syncroand101 says, sort out any rust and soak it in the stuff.

Yep - used the spraying variety, heated it up in a pan of water to get it nice n liquid like so it sprayed well, then covered the thing.

v-lux wrote:I also did this, stinks for a while, but its good knowing theres at least 'some' protection behind those panels.

Yep, don't sleep in the van the night you apply the Waxoyl. You'll wake up with something that feels like the worlds worst hangover.

Oh, and if you have time, take some pics of the stages - perhaps be good for the WIKI, I forgot to do this, will try when I do the front cab doors.

Post by **v-lux** » 18 Sep 2007, 08:57

ooooohh

I did take some pics actually!
Perhaps i should collate them and send em to a wiki type person?

Some of the pics can be seen here, though i do have lots more.

http://alanshaze.googlepages.com/

Post by **plurker** » 18 Sep 2007, 09:51

Post by **irishkeet** » 18 Sep 2007, 10:23

v-lux, syncroand101 & plurker

Thanks for all the help and tips
For the front doors I will be putting on a layer of sound dampening, then I
will be going with thermawrap (hopefuly this weekend at the JK techenders)

When I have some spare time im planning on gutting the inside of the van and treating the rust, waxoyling then insulating, not looking forward to removing all the westy furniture but i will take a lot of photos so if anyone wants them for the wiki no problem.

thanks again
keet

Post by **slowrunner** » 18 Sep 2007, 18:20

Blue Styrofoam has the best insulation value.
It's rigid, the stuff that is sandwiched between regrigerated trailers.They are made of a GRP/strofoam/grp sandwich.
The onl;y negative is that its a rigid material, so care needs to be taken with cutting.
If you find your local UPVC door manufacturing factory, they will probably sell you sheets of it.

Post by **mud** » 23 Sep 2007, 09:33

I have considered spray foam insulation (like the foam on a hot water tank) I used to live on a canal boat where rust is a real problem. The spray foam sticks to the surface of the body panel with no space for condensation to form- so no rust

It would probably be a nightmare to get out again but as there would be no rusting then would that matter?
Cost... well a 70 foot narrowboat cost about £1000 to do so I reckon a T25 would be about £100 if I can drive to meet the installer where he is already doing a job. It would take him about 10 minutes.