Very Damp (not Wet) Basement - General DIY Discussions - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > DIY Repair > General DIY Discussions

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Display Modes
Old 08-08-2008, 03:12 PM   #1
Newbie
 
Join Date: Aug 2008
Location: SW Ohio
Posts: 6
Rewards Points: 10
Default

Very Damp (not wet) basement


Hi all. New to the forum and largely new to basements.

My new house has an unfinished basement (roughly 30 x 75 feet) that's been framed, with the pink fiberglass insulation strips placed between the frames (paper side facing the inside). I would love to take the next steps toward finishing, but this basment is DAMP. So much that the staircase door at first wouldn't close.

There is no water. No leaks anywhere.

With 2 dehumidifiers I'm pulling roughly 40 pints of water out of the air about every two days. No mold that we can see/smell, and the home inspector found none. We did have radon, and just had a unit installed.

QUESTION: How can I dry up this basment? It's cool down there, but I see no condensation and have to think it's the foundation walls. Can I take the insulation down and spray seal the walls? It can't be that easy ...

Just wanna do it right before finishing. Any advice would be greatly appreciated.

Advertisement


Last edited by large; 08-08-2008 at 03:47 PM.
large is offline   Reply With Quote
Old 08-08-2008, 04:02 PM   #2
Member
 
ccarlisle's Avatar
 
Join Date: Jul 2008
Location: Montreal, Quebec, Canada
Posts: 1,889
Rewards Points: 1,000
Default

Very Damp (not wet) basement


Well, one thing you could do, with new construction is to treat the concrete down there with a penetrating sealant that reacts with the salts in the concrete (down about an inch) and seals moisture. Not vapour, but moisture. Water-white in consistency, it is a product that contains silicates, not a coating, but indeed something that reacts with the concrete below the surface.

A pail might cost $200 but I would spray that with a garden sprayer and then once dry, put the dehumidifiers to see what reduction in water you are getting. 20 pints a day is a lot...you might have to take down the fiberglass insulation but you can put it back OK.

I would do this once I had assured myself that all sources of water (like drainspouts etc) have all been managed to remove water from my foundations. Do you have a sump pump? You might consider keeping the air moving all the time too.

Advertisement

__________________
“The average American woman is about 25 pounds heavier than she was in 1960...Recognizing obesity as a disease will help change the way the medical community tackles this complex issue that affects approximately 1 in 3 Americans,”
ccarlisle is offline   Reply With Quote
Old 08-08-2008, 04:25 PM   #3
Member
 
Join Date: Jan 2006
Location: Toronto, Canada
Posts: 1,861
Rewards Points: 1,000
Default

Very Damp (not wet) basement


to do final inspection on all concrete walls... it may seems a waste of effort... but it worth it so that you are 100% sure you have no leak... because otherwise, how can you be so sure.... for those minor leaks does not show up from the other side of the insulation....

especially when you are going to have tons of work to finish the basement... take a couple of hours to take down all insulation for final inspection is a good idea.... also in where we are... it is a code you need to install a barrier between the concrete and insulation.... not sure if this is the case in yours....
KUIPORNG is offline   Reply With Quote
Old 08-08-2008, 05:12 PM   #4
Registered User
 
Termite's Avatar
 
Join Date: Apr 2008
Posts: 6,520
Rewards Points: 2,000
Default

Very Damp (not wet) basement


A moisture barrier between insulation and concrete is not a code requirement in the International Codes, although certain jursidictions can in fact mandate silly rules like that. A moisture barrier in addition to the vapor barrier on the insulation can actually cause problems in some cases. Arguments can be made for and against it.

To dry this out...
  • Sealing the concrete is a good idea.
  • Dehumidifier as required
  • HVAC (including return air) to the basement to condition the space
Termite is offline   Reply With Quote
Old 08-09-2008, 12:13 AM   #5
Newbie
 
Join Date: Aug 2008
Location: SW Ohio
Posts: 6
Rewards Points: 10
Default

Very Damp (not wet) basement


Wow.
Thanks guys. This rookie needed some specific advise. Now I know where to begin. I appreciate it.

A couple people mentioned treating with sealant (with silicates). Can anyone give me a brand to ask for? Can I get this at, say, Home Depot?

Regarding HVAC, I shut off the 2 vents downstairs because our second floor is hot (our bedrooms), hoping to get more cool air upstairs. Is this a bad idea?
large is offline   Reply With Quote
Old 08-09-2008, 12:29 AM   #6
Registered User
 
Termite's Avatar
 
Join Date: Apr 2008
Posts: 6,520
Rewards Points: 2,000
Default

Very Damp (not wet) basement


Quote:
Originally Posted by large View Post
Regarding HVAC, I shut off the 2 vents downstairs because our second floor is hot (our bedrooms), hoping to get more cool air upstairs. Is this a bad idea?
That depends on how accuractely the duct/HVAC system was designed. Closing off vent openings can effect the performance of the overall system in some cases. With HVAC, too few (closed) or too many duct openings for a given system can be a bad thing.

Your basement doesn't stand a chance of drying out without conditioned air in the summer and heated air in the winter. If it only has 2 vents in the basement, and you plan to finish the space, you need to take a good look at the adequacy of the system to heat/cool a basement of that size. Imagine having only two vents in a space of that size upstairs! You need an HVAC professional to evaluate your HVAC system and ductwork to see if more duct openings would help or hinder the HVAC system. Also remember that your ability to heat and cool and area is also very reliant on the return air in that area. With no returns down there, you'll never get it dried out or effectively conditioned.
Termite is offline   Reply With Quote
Old 08-09-2008, 08:37 AM   #7
Member
 
ccarlisle's Avatar
 
Join Date: Jul 2008
Location: Montreal, Quebec, Canada
Posts: 1,889
Rewards Points: 1,000
Default

Very Damp (not wet) basement


I don't know specifically if you can get concrete sealants at big box stores, like HD, I sort of doubt it, but there are several sealant products out there available from specialist companies on the internet.

As a benefit, these silicates also reduce radon intrusions...do a search on "Radon" and "Sealants" or some combo of those words.

If you're in Ohio, I imagine a vapour barrier on the warm side of the room would be called for. And the fibreglass insulation batts may have a sort-of vapour barrier built into the paper facing...I think it's code up here although minimum is 4mils plastic sheeting (we use 6mils)... just thought it made sense so never questioned the authority that would make it so. What you are trying to do is save money, protect your health and increase your confort but limiting the transport of moisture through your walls. By doing that, you decrease the chances of having mouldy walls thanks to condensation of warm air onto cold walls in the winter.

I also think it necessary to have good movement of air in basements...so keep the registers open down there and let the furnace fan circulate air throughout the whole house. Hopefully you do have a furnace fan, but if you don't, portables would do.
__________________
“The average American woman is about 25 pounds heavier than she was in 1960...Recognizing obesity as a disease will help change the way the medical community tackles this complex issue that affects approximately 1 in 3 Americans,”

Last edited by ccarlisle; 08-10-2008 at 08:28 AM.
ccarlisle is offline   Reply With Quote
Old 08-10-2008, 01:07 AM   #8
Newbie
 
Join Date: Aug 2008
Location: SW Ohio
Posts: 6
Rewards Points: 10
Default

Very Damp (not wet) basement


Thank you again for the great advise! And so I begin ...

Cheers

Advertisement

large is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
need help have a damp musty basement davidd HVAC 20 07-13-2008 09:32 AM
Basement mhughrob Remodeling 1 07-11-2008 08:11 PM
damp basement wall. itguru Building & Construction 7 12-16-2007 06:02 PM




Top of Page | View New Posts