Softness in drywall - small fix or major problem?

[radhak]

Talk of mold worries me. I had thought mold manifests in much more density that what I saw. At what point do I call somebody in to evaluate if (a) it is mold, and a lot of it (b) it needs professional eradication? IOW, is there something called 'just a little mold' that can be controlled? The only information online is from companies that cleanup mold, and they seem to have great incentive in amping up the scare value.

Not that I am not concerned how much mold might be there or might have spread. That softness must have been ages old, because the house is 10 year old while I stopped the sprinkler head just last summer. I am almost scared to look up costs of a big mold cleanup...

Jim, there is barely 1" of space between the drywall and the wall, so you might be right. And yes, I already see one furring strip (just where the small black tag is peeking out in the middle). The existing insulation feels more like old carpet falling apart - disintegrating threads and all. How do I confirm which is it? Or maybe it won't matter and I just buy whatever is available at the borg?

[parnelli]

Talk of mold worries me. I had thought mold manifests in much more density that what I saw. At what point do I call somebody in to evaluate if (a) it is mold, and a lot of it (b) it needs professional eradication?

Depends how paranoid you want to be... I personally would be fine with the project at this point.

Wear a mask, keep things damp and clean up as you go is what I'd do.

In addition to the mold, look how rusty that clamp is.

As others said, you've got to find the leak, or at the very least be 110% sure that the leak is no longer there before you patch this up.

[BigguyZ]

I agree with Parnelli. There's a lot of hypersensitivity and fear mongering regarding mold (and asbestos, but I won't get into that). I wouldn't call a remediation specialist in or anything like that. But I would cut out what you can. If you have to remove the bottom 16" for 15' in each direction, cut the moldy drywall out. Then I agree about using foam as an insulation. You can just glue it on (use the right adhesive- Locktite makes a foam-specific adhesive).

[radhak]

Thanks guys - you're giving me confidence along with good info!

I cut out some more, and have somewhat good news. The mold behind the drywall seems to be only below that rusted furring strip, and not much to the left or right of that area. I guess the water came in here and stayed here.

Have cut out the top and more to the left and right


This is the new top portion cut :


So, looks like the mold is minimal behind the wall, just from the floor to about a foot above.

But when I pulled the baseboard away, I see this :


Looks like mold, on the surface of the drywall behind the baseboard, stretching till almost 4 feet away on the right.

Good news that it is pretty clean after that till the end.



And on the left, there not much beyond what I have cut :



So I guess the project now defines to : cut sections of the drywall away; clean with bleach or whatever chemicals you recommend, and replace with new insulation and drywall. And of course dispose of the old stuff carefully. Right?

[Stytooner]

Personally if I didn't have much experience with it, I would have a handy man replace the entire wall. That is black mold and can be pretty bad on your health. Cleaning one side with bleach is not good enough remediation. It will still be present on the inside and may eventually grow back through. Best way is replace corner to corner with new insulation and furring strips. I didn't notice any vapor barrier either.
They have mold and moisture resistant drywall. Green board I think. I have seen some blue stuff on TV though, so they may have changed to that color.
That is the type that should have been installed to start with on a masonry wall.

[JimD]

If the outside of the wall is not completely sealed, in the summer time you have hot humid air that can get inside the wall. Cracks in the seams between the concrete blocks might admit enough air. When the air's temperature is lowered as it gets close to the inside, when it crosses the dewpoint, the moisture will condense. It will run down the wall and collect at the bottom. This seems to be a reasonable explanation of your observed moisture. But that would not explain why under the window.

Under the window still suggests to me that moisture leaked from outside at some point. I would throughly caulk around the window. Simple inexpensive potential solution. I use silicone. It might have happened awhile ago. Condition of the caulk should be a clue. If I saw gaps in the caulk, I would probably assume that is the source of the moisture.

Glueing rigid foam insulation to the block will help protect against humid air coming through the block. As long as the air stays on the hotter block side of the foam, it should not condense and thus no moisture.

When taping drywall in an area that might get wet or at least see high humidity - like a bathroom - I like to use the powdered drywall compound that comes in a bag. You have to mix it up but it keeps for a very long time and it is moisture resistant once you put it on the wall and it dries. You can also apply several coats in a day. Put the water in the container you mix it before the powder. It mixes a lot better that way.

Jim

[chopnhack]

+1 with Jim D, except don't glue the furring strips, tapcon them so you don't have to wait for the glue to dry unless of course you have access to a T nailer.

The most difficult portion of the repair is going to be blending the texture. I would suggest practicing on some scrap sheet good to be able to obtain the texture you are trying to achieve. It looks like a light knockdown finish which is achieved by throwing on a thinned version of joint compound and then lightly flattening it with a wide knife. The trick with blending areas is to sand an irregular width of the old section leaving you with a flat area to tape and a smoother transition from old to new. At least that works for me. Use a coarse sandpaper to cut through the latex followed by a sanding screen once past the paint. Don't sand through the top paper! Home Depot sells a pretty decent texture gun if you have a compressor, for the size area you have it will be cheaper than to buy the spray cans of texture. Good luck.

[radhak]

I had a Home-Improvement contractor take a look at it today, and he quoted me $425 to replace drywall for that whole lower section of the wall (16' x 32") - material and labor. I will know if that's the par cost when the next guy comes in tomorrow morning with his estimate.

Good thing? He looked at the traces of mold and said that was not even an issue - I should not worry about mold at all.

That said, I would have thought this would cost me only around $150-$200 including material;. $400+ is daunting. I might end up doing DIY if I can get the material from HD.

Btw, that guy says the insulation in the wall is a spray-on; If I can't find that very same, can I mix-match, with a different type of insulation?

[chopnhack]

Insulation can be mix and match, you are only concerned with r - value. Does the first quote cover matching texture? If it does then it doesn't sound like a bad deal, I know that its a significant outlay of cash, but there are some hours involved here.

If you have no equipment your out at least $100 or so just to rent a compressor and texture gun.

Your out of pocket DIY cost is about right, so you have to figure if the ~$250-300 which is labor is worthwhile. Like I said if its matching texture, and you can ask him to come and spray a sample for you to make sure he can do it, then its worth it. I have done some drywall and unless your pro, it is time consuming. You can get good results if you put the time in. A pro can knock out the repair in a day or two - the trick is using fast setting mud for the taping and spotting. GL

[radhak]

He said the insulation he'd use is R19, $40 at HD. Maybe I should ask him to use a rigid foam as suggested before to help stop moisture.

Yes, matching texture is included, and said he'd take 6 hours at the max, start to finish. That there is a strong argument for letting him do it!

I agree, other than the shock of sudden outlay of money, it's really not a rip-off. Maybe the second guy today will give me a choice of options.

I have a compressor but not a texture gun.

If this was not the living room, I'd not be considering paying for labor. Now with the risk of falling short of LOML's critical eye (time taken, end result), I'll go an extra C note to be done and over with. Might have to brown-bag my lunch for the next few months .

Oh yes, I still have to diagnose where the leak is and try and fix that from the outside. It definitely is not leaking rain : heavy rain this whole week and no new moisture. Shall go out with a hose soon and try; Jim mentioned silicone caulk.

BTW, chop, you had mentioned

I hope that is not a 110v line (14g?) running through the back of the wall like that! Typically they are supposed to use a stand off and attach it to a furring strip, not uncommon to see them run off of the 1x3 at the bottom when they run horizontal.

Well, looks like it is a 110v going to an outlet. That black rusted tab you see in that 1st picture is the 'stand off' (or used to be)! The guy says he'll replace it.

[pelligrini]

He said the insulation he'd use is R19, $40 at HD. Maybe I should ask him to use a rigid foam as suggested before to help stop moisture.

Not sure how he's getting R-19 in there. An R-19 fiberglass batt is 5 1/2", an R-13 batt is 3 1/2. They will compress, but it defeats the purpose of the product. 1" rigid PU foam is about an R-5. The polyurethane foams usually have the greatest R values for material thickness.

[radhak]

Great point - the second guy (John) had a look this morning, and said he'd be putting in a 1" rigid batt, and not the spray-in that was used before.

This guy seems far more in control - he identified where the moisture was coming in from (sealing along the window line on the outside is cracked open) and said he'd caulk it back, clean-up the baseboard and reinstall it, over and above what yesterday's guy would do (replace drywall, insulate, texture, etc). All for $350 too!

When I asked him if he could go lower, he smiles at me and says, "if my fellow contractors knew what I'm offering you, they'd accuse me of being cut-rate desperate...!" And he also pointed out that it will span across two days, to give time to dry and all.

Seems more reasonable (and he did not need to 'go back to the office to work out the estimate'!). I am calling him back to start the work. And since I'm working from home today I'll learn a bit too, I guess!

I should not forget to thank y'all gentlemen here. 'Talking' about it with y'all and working towards a solution is far more fun than doing it alone and wondering if I could have done better, if I missed something, etc. Of course, the family only wants it done and their room back to functioning!

Shall give you updates.

[BigguyZ]

Definitely sounds like the second guy is better. I liked the fact that he looked for the root of the cause, and not just the symptom. Only thing I'd add- make sure he removes the bad caulking completely, and doesn't just caulk over it.

I also disagree that you didn't have to worry about the mold. Do you need hazmat suits? No. But do you want to get that out of your house? Yes.

Also, I'd use the moisture-resistant drywall- even if you don't think you need to. It's been an issue already, so spending an additional $5-8 for the more expensive product is some cheap insurance.

[radhak]

You are right - dismissing it sight-unseen was a bit flippant. This guy pulled out the whole drywall before assuring me there was no mold problem, replacing the drywall would settle things. And he wants to spray that whole area with bleach to be sure.

I'll confirm the caulk removal. I think he's already factored in the moisture-retardant drywall. Thanks for the tips!