Exterior wall insulation

[exiled]

Hi,

Newbie here. I have the same problem Valerie does. but I don't even have any plywood underneath my siding.

I had to rip the back corner out because of faulty wiring that had been chewed through and discovered that other than some blowin in insulation (which ranges in places from 1/2" to 2" at the sides), that there is nothing else. No tar paper, in some places it looks like there is some kind of kraft paper of some sort.

So my question is this. I would like to get some 4'x8' sheets of the SuperCell FP Insulation which is like bubble wrap for insulating walls. but I'd prefer to put it on the outside instead of cutting it up and putting it between my studs.

Is is hard to take the siding off (or rather lifting it away from the bottom since I don't want to disturb my roof) and putting something in? If there is a bit of space for the paper and carboard they had in there, then this might fit fine, but my mom told me its hard to take siding off.

thanks,

[Greg]

What type of siding do you have? Greg

[Yanita]

Hi,

I am going to separate the last 2 post and hopefully create a new one.

Although they are sort of the same question they are different none the less. We encourage everyone to create their own threads so every question gets answered. Having multiple situations in one thread creates confusion.

Thanks,

Yanita

[Yanita]

AHA! I did it, please carry on.

Yanita

[exiled]

My siding looks like the original aluminum. I noticed that the wall that had the water damage last year is one that gets a lot of snow up against it...

Is that a bad thing? should I put some heat wire on the outside where the snow gets really deep? that would make a lot of sense why I have rot in that corner. I am worried because it is getting in to the floor and the floor joists.

[JD]

If this is vertical aluminum siding (usually approx 3x8 sheets going up and down), it is easy to remove and reset. Usually there is a trim section at the top where the siding just slides into a sleeve like area. If an awning has been installed where screws are going through the siding panels, this can make removal much harder. Doors and windows would need to be removed to get the siding out from behind them. Any seams with major dents and distortions will be pain as well.

Generally, vapor barrier would go to the warm side of the wall. In cold climates, it would be behind paneling or gyp board, in warm climates, it would be behind the siding. The brown kraft paper you saw was what he manufacturer used for vapor barrier. What you do not want to do is have vapor barrier on both sides of the wall because this will trap moisture.

Personally, I would do the work from the inside of the wall. I think whatever you end up doing, it will be easier than removing and resetting the siding. If you have water damage to the walls or framing, you may need to remove both sides to make the repair.

JD

[Greg]

It's easier to just shovel the snow away from the wall if you know there is a problem. Greg

[waitingtohear]

I also have wall insulation issue\question.

I tore down the old wallboard to replace with new. I am also replacing the 40 year old 1 inch fiberglass with styrofoam sheeting insulation. (better per inch in R value than fiberglass)

But I notice that the thin plastic vapor barrier (which for the most part is still in good shape after 40 years!) has water condesation on both sides! I don't care about the outer side of course, but the inner side is going to come into contact with my insulation. How does this happen? I thought the barrier was there to keep water out. How is it being transferred to the interior side? How can I stop it from continuing before adding the new insulation and wallboard?

[Dean2]

Moisture won't hurt styrofoam,least not to My knowledge. the thing to ponder is wether it will condense/concentrate enough to gather on untreated wood and cause rot or mold. The styro will work as more vapor barrier if fitted tightly in the stud cavities. Use nothing for barrier inside and replace any solid vapor bariers under the siding with Tyvek type material,,it is moisture resistant but breathes to allow vapor to dry. This is a slow process within the wall unless,of course,the siding its-self breathes alot.

[[If My answers make perfect sense to anyone---please make an emergency visit to the nearest Shrink! ]]

Dean

[Dean2]

"Use nothing for barrier inside"

Nope,,strike that line!

Use a solid vapor barrier inside,under the sheetrock or panelling,,use the Tyvek under the siding so vapor/condensation can escape thataway!

Sorry bout that,haven't had My full dose of coffee yet!

Dean

[Yanita]

Hi,

Do you have a single wide or a double wide?

Yanita

[waitingtohear]

I have a single wide. But everyone is giving answers based on the fact I mentioned I was using Styrofoam. That part, I have under control.

Perhaps I should not have written all that.

My only question was:

I see a thin sheet of plastic vapor wrap that was applied to the outer side of the house frame before they installed the aluminum siding. There is condensation forming on the plastic side which faces the inside of the walls. (actually there is water on both sides of plastic but at least the outer-side is not the problem) I'm baffled why there is condensation forming on the interior side.

How does that happen? Does this form on interior side because warm air is escaping through the wallboard and very thin fiberglass and ends up hitting the cold plastic barrier?

I'm trying to understand how it is accumulating before I worry about how to fix it.

[Yanita]

Hi,

Your correct, cold meets warm = condensation.

Yanita

[waitingtohear]

yes, I have been doing some reading and now see how it happens. This expains why it is a much bigger problem in the walls of the kitchen than it is in the back bedroom.

Now that I understand this I am wondering if I am better off taking the original vaper barrier down since it seems to be on the wrong side of the wall studs! It's not on the inside, but outside! I'm going to use "faced" fiberglass insulation. That will put the vapor barrier on interior side where it should be. So I don't understand why they put this plastic on the aluminum wall side. IF I leave it up, won't that trap the vapor that does make it's way through the walls and dampen my insulation?

[Dean2]

Yes it will. When You remove the siding to get rid of the solid exterior plastic,relpace that plastic with Tyvek or a "beatheable" substitute,apply it as per instructions.

At present,maybe keeping the hunidity indoors a bit lowaer will help,it is harder to heat dry air but if it keeps the moisture in the stud cavities down it might help reduce condensation damage.If the moist air is infiltrating from the outside then lowering indoor humidity will only do "just so much".

If the siding is what I think it is *do not" caulk it shut tight,especially along the bottom,any moisture that does form of leak in needs to run out the bottom.

Dean