Wet Insulation Basement Walls

[hockeyhockey]

I am having a house built, the basement walls are poured concrete. The basment walls are framed and insulated with FibreGlass insulation and then covered with a vapor barrier. The problem is there has been so much condensation the insulation is soaked on the side that is against the concrete wall. Just now the builder has put in a big fan and dehumidifier in the basement to circulate the air. The AC/furnace has not been hooked up yet.

I dont want to take possesion of a house with wet insulation in the basment. What agruments should I use with the builder on my walk through to get hime to replace it? What should I get him to do? I have a feeling it wont be a smooth walkthrough.

[Bobk207]

With the vapor retarding membrane in place...it's going ot be a long time drying that insulation out. What was the source of the moisture?

Aren't foundation concrete walls normally insulated with rigid board on the outside? (at least that is my limited experience with insulated foundation walls in mountain regions of CA & NV)

Something doesn't seem right here.

Here's a rather lengthly report on basement wall insulation systems, depending on the local year 'round climate conditions....your insulation system may not have been such a good choice. I'm no expert of these installations but if you've go moisture issues at walk through that would seem to indicate a design or construction problem.

I found the report a little confusing in the begining (plus I was reading it on screen.....I do better with paper report)

but it you read & understand most of it, you'll well enough informed to discuss the problem with your builder.

Some insualtion systems require A/C or active de-humidification to avoid moisture problems. Hopefully you live where moisture is not a huge issue but I'm thinking not. :(

My original question(s) still stand......how did it get wet, how will it dry with a membrane in place AND what will prevent this situation from happening again? (after you've signed the final check)

be careful

cheers Bob

[hockeyhockey]

Bob,

The source of the moistue is condensation...and yes How will it dry with the vapor barrier in place? Condensation is from the concrete being cold and now with the warm air in the house it beginning to sweat it out.

[Bobk207]

The "vapor barrier" is supposed to keep the moisture in the warm interior air from migrating through the insulation, contacting the cold concrete wall and condensing.

If the "vapor barrier" is working very little water vapor should be reaching the cold wall.

Either the membrane is compromised or the source of the moisture is elsewhere.

cheers Bob

[Chris]

Hello Bob,

my opinion is that the insulation and membrane thing was put on much too early, so the "rest water" coming from the concrete is now in it, plus condensation. I think the best way is to start all over again and rip it of, let the concrete dry out at least for a couple of months and then put a new insulaton on that can breath, so to say. Otherwise you might have the chance of the material to rot later on in some spots and then you have a good chance to get mold. Fungicides are not funny. And then you have to decontamine the whole place for the spores will be all over the builing and in everything in it ! Just tell them that you won't accept it that way and they have to come up with a propper solution and I think there is just that one. Keep enough money back so they have to do it right. You might also contact an external expert.

[Chris]

Ops, it was not ment to Bob, but to hockeyhoc !

... and in case they stopped the natural drying process, you could virtually drag it out by force. Please see

for more infos.