[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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[JP4]

I've had good luck just using the Thinsulate in my windows all around van. Since it doesn't absorb water, I'm not too worried about moisture. It's a nice one step operation for insulation. The only time I get excessive condensation is when sleeping in the van with three people with the windows closed. With the roof vent cracked open and the front windows open a few inches, I get no condensation. I have Reflectix window coverings that help as well. I never get condensation with my little ceramic electric heater running, regardless of having windows open.
As a side note, after a year of driving and sitting in the rainy PNW, I've seen no evidence of water getting in the holes where r exterior trim attaches. It looks like it should come pouring in, but has been completely dry all around.
JP

Sent from my SM-G900P using Tapatalk

 

[cargovanconversion]

Good to hear of the overall 'dryness' of the van. I'll be using many of the same technique to avoid condensation (open windows, roof vent, etc).

I haven't decided on the wall insulation yet, but tend to favor poly-iso. I just don't like it to be exposed to water/humidity and if it happens and it will, the water should be able to drain itself or dry out.

Van Williams

 

[orton]

I just bought a small Eva-Dry model EDV-1100 dehumidifier for $48.00. For an additional $13.00 I will buy the optional 12 volt DC power cord. Will see how that works to reduce or eliminate the condensation inside the van. We will see. Sticker on unit says 2.5 amps @ 9 volts DC.

 

[cargovanconversion]

I just bought a small Eva-Dry model EDV-1100 dehumidifier for $48.00. For an additional $13.00 I will buy the optional 12 volt DC power cord. Will see how that works to reduce or eliminate the condensation inside the van. We will see. Sticker on unit says 2.5 amps @ 9 volts DC.

I take that the above means that you have a condensation problem? And if so, how does it manifest itself and what is causing it?

Van Williams

 

[orton]

I take that the above means that you have a condensation problem? And if so, how does it manifest itself and what is causing it?

Van Williams

In the mornings occasionally I have had moisture on the inside of the glass and some metal parts that are not insulated. I assume that that condition occurs when it is warm during the day and it gets cold at night. As the interior air of the van cools toward the exterior temperature it gets past the dew point and the moisture comes out against the cold parts. People also produce moisture when they sleep. I do not run a heater at night to keep the van temperature high. I use a 12 volt heating pad under the sleeping bag to stay warm.

Suspect the small dehumidifier will eliminate the condensation. I will let you know how well it works next winter.

If you have locations where the interior air contacts the cold van steel, you can get condensation even if you can not see those locations.

 

[GROOVY2]

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-

Available

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 -

 

[cargovanconversion]

In the mornings occasionally I have had moisture on the inside of the glass and some metal parts that are not insulated.

Most of what you describe will likely happen in very RV. But I wonder, if you have seen that window condensation drip into the wall and collect at the bottom.

Van Williams

 

[orton]

Most of what you describe will likely happen in very RV. But I wonder, if you have seen that window condensation drip into the wall and collect at the bottom.

Van Williams

No.

I did see a new van on the Ford lot with about 2" of standing water in one of the lower cavities. I also could not find drain holes in my van. I used sealant on all the black trim fastening holes/fasteners on the inside before I insulated and closed up the openings with panels.

 

[cargovanconversion]

used poly-iso as 2nd layer of insulation - and Thinsulate

Did you install the poly-iso against the skin of the vehicle, with Thinsulate on the inside?

My thoughts with regard to the subject of this thread are, to perhaps create an airspace at the skin, followed by poly-iso and Thinsulate. The inevitable condensation from the windows could then drop along the skin to the bottom of the wall without reaching the insulation. Remains the collection of water at the bottom of the walls that doesn't have any weep holes.

Van Williams

 

[orton]

My approach was to eliminate air pockets against the van steel as much as possible. No air contact means no moisture condensation.

Window indents have polyiso glued to the steel and the voids filled with Great Stuff. Lower and upper deep wall sections have two layers of 1" Aerocel closed cell foam glued to van wall and each other. Then a layer of Reflectix on the closed cell foam, a 2" air gap to the 1/4" plywood wall covering. The ceiling is filled with polyiso with gaps and ribs filled with Great Stuff. A layer of Reflectix on the polyiso, an air gap to a layer of thin white Thnsulate that sits on top of the Macrolux polycarbonate twin wall greenhouse ceiling panels.

 

[jonsobi]

Van,
When I installed my polysio board on the sides and ceiling, the natural side-ribs and curves of the van seemed to provide a decent air space behind the flat boards. I taped it using Tyvec builders tape which provided as much air tightness as I wanted or deemed necessary. I used pink attic bats in the lower stuffed areas, paper side in.

I do not have a roof vent. We use front window screens, and a slider window screen only. We have not done any extensive below freezing sleeping.

We have not experienced any problem condensation as of yet. Tomorrow I will be detailing my van after several weeks of touring, and I plan to inspect all lower cavities for moisture.

Will post the results.

 

[GROOVY2]

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 -

 

[GROOVY2]

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 -

 

[JP4]

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-

Available

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 -

Someone here mentioned (maybe it was you Groovy?) using the foam poly board with fabric over it for the interior panels.
I think this is the way I'm going to go for my ceiling and upper walls above the windows (I already have the factory plastic load protection panels on the lower areas and doors. Those have held up great over the last year btw, highly recommended). I'm going to have L track running down the middle of the ceiling and on the edges of the ceiling, so the panel's only need to be a couple feet wide at most. I'll cover it with some automotive speaker enclosure fabric that's fairly inexpensive. The panel's should be light enough that I could probably secure it with some heavy duty Velcro. Should add a little more insulation as well.
JP

Sent from my SM-G900P using Tapatalk

 

[cargovanconversion]

This started the whole conversation.

Ford Transit - Condensation Simulation

As you can see, if the insulation is attached to the skin of the vehicle, (inevitably) condensation from the windows will get into the side walls and moisten the insulation and finally collect at the bottom, where rust will appear (there are no weeping holes).

Van Williams

 

[GROOVY2]

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 -

 

[cargovanconversion]

-

Lots of good ideas.

Van Williams

 

[AngryVanMan]

Would it not be easier or better to control the flow of the condensate rather than let it settle into a likely inaccessible area? You probably don't want to permanently glue or stick anything directly on the base of the glass, as that may interfere with replacing it, if the need were to arise. Perhaps when 'framing' out the window region, some closed cell foam weatherstrip or rubber channel moulding could be used at the interface between the frame and base of the window. Control the direction of dripping water from that point.

edit: I think this might be along the same vein as GROOVY2 mentioned with the color match caulking/plastic trim. Our cargo vans don't have factory trim, but basically the same idea.

 

[cargovanconversion]

Would it not be easier or better to control the flow of the condensate rather than let it settle into a likely inaccessible area? You probably don't want to permanently glue or stick anything directly on the base of the glass, as that may interfere with replacing it, if the need were to arise. Perhaps when 'framing' out the window region, some closed cell foam weatherstrip or rubber channel moulding could be used at the interface between the frame and base of the window. Control the direction of dripping water from that point.

The window frame/sill very likely will have a rubber seal (against the metal), but the condensation will seep behind it, directly into the wall cavity.
From what I've seen, heard and read, I won't be able to stop the condensation (although I'll put a lot of effort into ventilation), so in all likelihood I will caulk the plastic exterior panel holes/connections shut, create a few weep holes at the bottom and avoid placing any insulation against the skin of the vehicle, but use an airspace first, followed by poly-iso and a flexible insulation such as thinsulate or denim.

So your correct, it is more about control of the (possible) flow. I see no way of preventing it.

Van Williams