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Window Condensation

8282 Views 27 Replies 6 Participants Last post by  cargovanconversion
I'm preparing to work on the walls of the van, and I have to prevent, that condensation from my 'All-Around Windows' has the opportunity to get into my insulation.

I noticed that at some points, water can seep into the walls underneath where there are no weeping holes.

General question: How is your experience with condensation on the windows?

Specific question: What have you done to keep that wall space underneath the windows dry?

I thought of gluing insulation board against the skin of the vehicle, but now wonder if I shouldn't use an airspace first.

Van Williams
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used both Thinsulate and poly-iso on my van -

No problems so far -

used poly-iso as 2nd layer of insulation -

I like it - strong -easy to cut - sands to shape
will bend if you cut slits in it -
Easy to add layers //
easy to glue -3M#90 does not melt it-


3/4 "poly-iso has foil on both sides
so it is a Radiant barrier if used properly

this has ++s and minuses --

I used Aluminum Duct tape / glue to hold poly-iso in place -
using tape formed a thermal bridge from van metal to Inner skin of poly-iso

to Break the bridge

I just made a Slight Cut with knife around edge of insulation board
thru the aluminum - simple -

Thinsulate is the Easiest /Fastest to do by far -
especially Inside walls/bracing -

3 weeks ago had thick fog - van insulation not complete -
working on van -
metal that had no insulation was wet
insulated areas not wet - surprised me -
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my plans has changed through time -
once it hit 90+ figured would add to insulation I had -

so added poly-iso - you will have to see what I did
no way to easily explain -
am done with insulation mostly -

I am going to put some poly-iso directly against interior van flat ish wall
from ceiling to above window area - 3/4"- cant hurt - somewhat wasted space
have high roof extended -

part of my insulation plan has been to have a way to Pull air through
upper part of walls and roof insulation area to remove heat -
going to be in mostly hot climate -

purchased 8x 12 v centrifugal fans - from some type of office equipment-
fans have speed controlled by temperature that can be bypassed also-
fans are 38cfm and will pull some negative pressure -

4 of these fans will be mounted Outside Under van using
Rear C frame that rear doors are attached to for Hot air
removal channel - -Duct work -

Fans mounted at holes on bottom of channel where black plastic plug covers-
4 fans -

1 fan(each side) mounted at rear door that pulls air thru wall insulated area
that exhausts into channel -

this will pull air from upper roof and wall area -

Not sure Im going to keep this van or I would just put in roof vent -
but would use similar type of air draw through insulation with roof
type vent when wanted -
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to remove air moisture in cool location -
I did not insulate a portion of rear drivers side door-
going to install computer fan inside door that draws humid air
from inside van thru speaker hole and blows against cooler metal of roor skin -

will depend on temperature how good it will work -

weep hole in door was taped over by factory for some reason -
now removed -
Im not worried about rust

areas that you think may rust or have water pool
can be coated with LPS#3

LPS3# will not let rust form - it works -

Used it on all of my machine shop gear -

Also used it to coat inside of swamp cooler ACs -
parents 30 years old AC had Zero rust
when it was replaced with a more efficient unit -

Swamp cooler water is close to sea water in corrosive -salt -nasty

LPS #3 can be applied with a brush or sprayed on -
little smell -and goes away completely in a day ish -
it has slight brown color like watered down coke -
Down side where LPS#3 is applied No glue will stick -

Have not applied to my van yet but but will soon -

also polyester cloth used in clothing like Coolmax or Drystar can be used
to wick water away from areas and this cloth will evaporate water quickly -
it is amazing stuff -

If I had windows would run a strip of this cloth along bottom of window
to evaporate water -

if I cover insulation with cloth will likely use this type polyester cloth -
also I found water in lower frame area after rain -
sealed trim screws with caulk - fixed it -

But now think that caulking top edge of plastic trim would be better-
Found some that color matches great -

weep holes are poorly designed -
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