Okay, I'm really confused and depending on what I read and who I talk to I get different answers.

I'm remodeling my basement. On most of the exterior walls, the previous homeowner has a vapor barrier against the block wall, then studs, insulation w/ the kraft paper facing the warm side and finally drywall. I've noticed that when i run the heat (kerosene for now but when finished, electric baseboard) that moisture builds up and soaks the insulation and the base plate. I'm not sure what to do to correct the problem. I've been told that the vapor barrier should be on the warm side not directly against the block wall, I've also been told that where I have the access that I can simply add another vapor barrier to the warm side of the room, or I can cut through the kraft paper then add another vapor barrier to the warm side of the room. Help! I'm not sure how to proceed. Also, what do i do about the walls that have already been finished. Won't the moisture continue to build and mold the insulation and drywall? I should note that I live in Central Pa so it does get cold in the winter and hot in the summer.

Thanks

 

Penn,

Based upon what you are saying it appears that the lack of ventilation may be the problem within the lower level. Moisture that you are experiencing may be created by the kerosene heater. These can kick out alot of heat and mositure. I have attached a couple of links that describe this in more detail. Lack of ventilation will cause problems with this if you are not providing other means for ventilation.

If traditional framing method was used, new walls should be 1" from the vertical block/masonry surface if using R-13 insulation. The reason to keep the wood out from the walls is the moisture that could damage them. If using insulation like R-19 and only 2x4 studs, the insulation would touch the walls. I have stated before that if a homeowner did put thicker insulation in, and the wall was only 1" from the masonry surface, I have recommended hanging a vapor barrier between the back of the wall and masonry surface. This doesn't allow for the insulation to touch the wall and air movement is not restricted but at least you won't create damage to the insulation or wood. If you do want to increase the R value, move the wall out further or use the R-13 and then apply a rigid insulation over the studs (warm side) then drywall (not paneling) *Code advises a 15 minute fire rated material over any rigid insulation - 1/2" Drywall*..

Kraft Faced insulation is fine to use in the above scenario. No need for the poly and you can do everything easily. You may find this easier and I would do this versus unfaced and vapor barrier because I don't like to play with it any more than I have to.

http://www.tenantsunion.org/moisture.html

http://doityourself.com/hvac/smallco...aceheaters.htm

I would discontinue the use of the kerosene heater as this is a major cause of your problems. Mold and Mildew require moisture, lack of ventilation and organic matter to grow. The issue with excessive heat created by kerosene which creates moisture and lack of ventilation will create problems if continued.

Hope this helps!

 

Okay just to get this straight. Someone tell me if this is right. Here's what I'm currently doing. Building a 2X4 wall with a 1" gap from the foundation wall. Then I'm gonna use R-11 Kraft-Faced insulation which is onsale at Menards this week for $7.99 for a 15"wide 50Sq. ft. roll. Instead of $7.77 for the unfaced stuff. Now since I'm using this Kraft insulation I don't need a vapor barrier right? Since the Kraft will act as the VB?

So is this OK?

Cement wall > 1" gap > 2X4 stud > Kraft insulation > Drywall

 

Bluestraw,

You got it right! But you can use R-11 or R-13.

Have fun!

 

Just got back from Me-Nards with some R-13. I originally went there with the intent to purchase the R-11 Kraft which was on sale for $7.99(40') in their ad. Nowhere in the ad did it mention that the R-13 Kraft(32') was $7.33 regular. So, the R-13 is like $0.03 more per foot. I was comparing the two & the R-13 is stated as being 18% more efficient. Is this some sort of secret in the insulation world relating to price? If so, I apologize for spilling the beans. Anyone notice the title under me screenname?

Blue

edit: Also, do I run the insulation all the way up to the upperlevel floor? Or do I leave space up in the joist for vent. I'll also be insulating the Joist ends by doubling up R-13 or R-11. Since I'll have some left over. Oh yea, gonna have a suspended ceiling also.

 

Bluestraw,

I would place insulation up the entire height of your walls and as you said insulate your rim joist areas.

Nice info on insulation at the store, huh?

Good luck!

 

Woah!! 7 minute responce time! Excellent service here!

Yeah, what sucked was the fact that I didn't realise the $$ dif till I had pulled into the yard to load teh R-11. Ended up going back into the store for the return/swap hassle. Oh well.......

Off to get dirty now.

Thanx again.

 

Got another question here.

First off though. Sorry about hijacking your thread Penn.

Doug,

Would it be alright to run wire in the 1" or should I just drill holes throught the 2X4's? I'll be running wire, cable & phoneline. Cable is going straight up & wire and phone line are going sideways.

Thanx,

 

Bluestraw,

No harm in running your wire behind it or drilling holes through the 2x4 studs. It's your choice. It won't hurt anything. You may want to suspend the wires at intervals along the way to avoid any wire strain, if you think it needs it.

Hope this helps!