Insulation, Radiant and Vapor Barriers - Metal stud framing/cement wall/moisture barrier?

First of all, I would like to thank everyone who contributes all of the great information to this forum. This is my first post after reading over the threads for several days. On to my questions:

I had a house built about 3 years ago (Chicago suburb) with a full unfinished basement. The walls are poured cement and the whole basement is below grade (maybe a couple inches of the wall is above). The land around the house has a very nice grade to it and drainage as I have yet to hear my sump pump have to kick in during a storm (and I have checked it's operation). Maybe it has and I just haven't heard it. Basically, there are no problems with water or moisture whatsoever.

I've begun the project of finishing my basement, starting with the framing. I am using metal studs with the metal tracking for the top and bottom. I have all of the track finished, leaving a little gap between the track and the cement wall. (Actually one section of one of the walls is a little out of plumb, so the metal studs actually touch the wall at the very top.)

There are so many threads on here about it, but my question deals with the need for insulation and/or a moisture/vapor barrier. My thought are as follows:

1. Moisture/vapor barriers
Since I have a recently built house, and the walls are poured, I should be OK with just the external moisture barriers already applied. And even if not, I am using no wood, so there should be no problem with rot if moisture did get by. Also, I sort of want to stay away from any moisture or vapor barriers to enable the walls to "breathe". I don't want to keep moisture in my basement, if at all possible, and want to give the moisture as many paths back to the outside as possible, whether it be moisture that came from outside of moisture produced from the inside. Installing a barrier would block a major path...am I correct in assuming this? I would just like a natural equillibrium to occur with the outside.

2. Insulation
I already have ducting and vents provding heat to the basement and I feel comfortable downthere in the winter. Do I need insulation? Is there another reason to get it other than simple temperature control? I think not using insulation would help for warmer summers, where the basement stays naturally cooler. This may cause a little more moisture potential, but leaving off any type of moisture barriers (as noted in #1) should help to expel this.

So basically, I am planning on not using any insulation or vapor/moisture barriers. Is this a bad idea, good idea? Does this make any sense regarding the type of walls I have, below grade basement, etc.

Thanks in advance,
Eric

l2r99gst, Welcome to the DIY Forums.
I am moving your post to insulation as to give you the best answer to your questions. Good luck with your project.

#1 for sure hang a 6 mil poly on that cement wall and then over studs and insulation paper side to the roomthen the drywall.

#2 for sure a R13 insulation.

So basically, I am planning on not using any insulation or vapor/moisture barriers. Is this a bad idea, good idea? Does this make any sense regarding the type of walls I have, below grade basement, etc.

For sure dont do it that way. Also check code you might have to cut in the outside wall a new opening to get out of the basement
Then that bottom track for the metal studs should be up on a P/T 2X4 so it dont rust out right away.
Been doing it with the V/B both side for over 25 years now, and it works.

ED ;)

Based on everything I have read so far, I thought you do not want any type of poly/barrier directly on the wall. Unless, you can have it drain under the slab. If I put poly directly on the wall, moisture could condensate on the plastic, drip down and puddle on the cement, providing a good environment for mold/mildew. Am I misunderstanding something?

For #2, I'm not building a bedroom, so I don't think an egress window is necessary, is it? Also, for the insulation, why shouldn't I use any. I know you said I should, but what are your reasons? Are there any other besides temperature control?

For the metal track, it is already fastened to the cement floor. But, if I don't use any vapor/moisture barriers within the walls, there shouldn't be a risk of puddles accumulating to rust out the metal, should there be?

Maybe I am misunderstadning something, but basically I thought we do not want to trap any moisture anywhere, but give it the ability to exit.

Thanks for the replies.

I did a quick search on Google and found information supporting what I am asking. This site (http://www.radonseal.com/basement-remodeling.htm) has a section toward the bottom entitled "How NOT to Finish Basement Walls!"

To quote it:

"Most finished basements are constructed with interior insulation – stud wall framing filled with paper-faced fiberglass batts, often covered with polyurethane vapor barrier, or fiberglass “blanket” insulation with impermeable vinyl or aluminum interior surface. But according to the latest research, this common construction is unsuitable for the building home industry due to serious problems with mold, decay, and odors. (Building Science Consortium) It traps water vapor coming from the exterior, small leaks let humid interior air reach the cold wall, and any ground water seepage cannot dry out.

"The use of vapor barriers (polyethylene or vinyl wall coverings) has caused many building failures and facilitated the growth of molds in many buildings. The wide spread use of double vapor barrier basement wall in Minnesota has resulted in many failures, in some cases within a year of construction."


Can anyone comment on this and explain to me why I would want a vapor barrier.

Thanks again

As I said over 25 years at it been back on lots of the jobs they all worked fine and no call backs. Have also did earth contact homes this way. That steel track on the cement floor will rust out. :D

ED :thinker:

Ed,

I value your input and I truly appreciate it, so I hope I'm not coming across as being inconsiderate or anything similar.

But, in your first reply to me, you mentioned poly against the wall and then poly over the studs and insulation. That is basically making a moisture trap, if there is one little leak somewhere in the poly. Have you ever thought that this is why the metal track in rusting out in your installations?

Again, I am just trying to gather information. You know a lot more than me and I appreciate your replies. Can you comment on the link I posted or my other questions, too.

Thanks

Have had no rust in any of the studs or track CAUSE base track in up on P/T wood. Also like to use wood stud if we can with P/T bottom plate. went to that www of yours all I see is they want to sell sell sell to you. As I said If you show me yours Ill show you mine . :D

ED :coffee:

I have read much about this topic also. I am building a basement rec room in good old Southeastern Wisconsin :cool: . My home is 10 years old, poured walls. I am going with 2x4 walls, no insultation, and a vapor barrier only betw the drywall and studs. This is a method I have seen used effectively in my region for the past 5 years without any problems in newer homes.
Just make sure there is air flow to behind walls for exchange, don't make it air tight. Also, make sure you don't have an exsisting moisture problem in your basement. Good luck with that project! :thumbup:

Floyd,

Thanks for the reply. The method that you have described is what I am leaning towards myself. You are in the same climate as myself, also.

If I decide on a vapor barrier at all, it will be only between the studs and drywall. I'm still trying to do some research about insulation and vapor barriers, but doesn't some insulation already have a vapor barrier on it's face. Also, doesn't some finishing primer/paint for the drywall act as a vapor barrier? I am leaning towards this as a plastic/poly vapor barrier will never be a perfect seal anyway, after putting staples/screw in it.

There should be place for airflow since I will build some sort of suspended ceiling. I will caulk along the bottom track, but should I do something along the ceiling and wall or leave it unsealed for breathing purposes?

No existing moisture problems. Thanks for the word of encouragement. I'm just trying to get as many opinions, facts as possible so I can do it right.

Thanks

Actually I put the vapor barrier betw the basement wall and studs, not studs and drywall, you can use insultation that is faced, that provides a vapor retarting affect. The idea is to prevent warm moist air from the rec room from coming in contact with the basement concrete wall that is cool and may cause condensation. Running a dehumidifier is highly recommended during the spring, summer and early Fall to keep moisture lvls down in the basement.

Floyd,

If you put a vapor barrier against the cement wall, on the cool side of the insulation, then that vapor barrier will also be cool. Any warm, moist air that gets past your insulation can condense on your cool vapor barrier. This can eventually soak your insulation and studs of your wall, causing mold and rot.

I think that if you use a vapor barrier at all, you need it on the warm side of the insulation. And actually, I just came across a site that suggest for people in the midwest (you and me), a vapor barrier may not even be necessary due to our changing climate. Leaving one off will allow the moisture to pass through the walls, ceilings and floors in either direction during the changing seasons.

Here is the link: ebuild info (http://www.ebuild.com/guide/resources/product-news.asp?ID=96715&catCode=15)

What do you think?

I don't do the insultation, this leaves a air flow space, with the dehumidifier and air flow the inner wall space stays dry. The vapor barrier prevents moisture from basement wall coming into the dry wall. I like the idea of either solid insulation or none, I would worry that fiber insulation would wick up moisture and decrease airflow. I have seen just about every opinion on basement vapor barriers and insulation, everyone has a different opinion, thats what makes this such a great topic :wall:
I try to think thought things before I do them. However this is a project that seems it can be done in many different ways, some say a vapor barrier only betw studs and drywall can cause moisture to collect betw outer wall and studs, causing rot.
I figure if you allow for air exchange, don't have a exsisting moisture problem, and keep the basement relatively dry, things should be good. What do you think?

Hey, just read that web site, that does it! Out with the vapor barrier, thank goodness i haven't drywalled yet :D I am not insulating either, I will have wired in electrical baseboard heaters about in the basement which should keep it comfortable, they will be tied into two separate thermostats. I will be putting in a suspended ceiling, as i think more on this, I don't get moisture on my walls now, why would i want to add vapor barriers that may trap moisture?
If i have good airflow, wouldn't that keep both the dry wall and concrete walls dry?

You both might want to check code there where you are. Lot of codes now call for a fire stop in that space behind the studs at the sill plate and joist. So there goes the air to make things dry. Have been hanging the V/B on the wall and over the insulation for over 25 year.Have had not one bad job with it.

ED :wall:

Floyd,

That's what I am thinking. I am just trying to make the best sense out of all of this.

Ed,

Just saw your reply. I understand you have been doing it that way for 25 years, but have you torn down every job to see how much moisture is getting trapped? Have these jobs been in a midwest climate where there are hot summers and cold winters and were the basements conditioned?

I'm not saying that your jobs didn't go well or are wrong, but I want some explanation along with it to state why it is or is not needed and what will happen with it there or without it there.

It just makes a lot of sense to me that in a changing climate, there will be moisture flowing through the cement wall in both directions (in the summer with an air conditioned basement, moisture will want to flow in from outside and in a heated basement in winter, moisture will want to flow through the wall to the outside). If you block it in one direction, you will condense the moisture on any cool vapor barrier surfaces. In the case of two V/B surfaces like you are talking about, even if there is one small hole in one of them, you will get condensation on the cold one, and a very hard time for it to evaporate/escape due to the two sides of V/B. I think this would cause a possibly moist environement within the wall that can either rust metal, rot wood, or encourage mold/mildew growth. Wouldn't having no v/b for changing climates be the best. The link above suggests this also.

Does that make any sense? Again, I'm not asking if your jobs went well...I am asking if this makes sense for these conditions. I don't know where any of your jobs were at or what they looked like.

Thanks

Fire blocks only required if using various forms of insulatoin for my area per code. :thumbup:

l2r99gst As I have said been back on many and had no trouble at all with mold. Where at In "central Missouri " some winters down to -15 and summers to 105o


ED :D

Holy Moisture Headache from above,
I am just starting to build my walls in my basement here in michigan.I have heard the whole nine yards on the vapor barrier from all sides and still cannot make a decision.Also,my poured foundation has 5 cracks that were repaired and filled with epoxy and gauranteed for 5 years.I am afraid of covering these up as well.i can have a storage room for three along my longest wall to keep an eye on them.but like i said the more i read the less i know on what to do in my own situation. good luck to all