Mold with hard deposits


Old 06-11-05, 09:09 AM
Thread Starter
Join Date: Mar 2003
Posts: 24
Received 0 Votes on 0 Posts
Mold with hard deposits

This is our first spring in our new house, and after our oppressively rainy and damp spring (in the Boston area), we've developed what I assume to be mold on some joists in our basement.

We've just bought and got running a 50-pint dehumidifier for the basement, and are in the process of scrubbing the mold off the joists with diluted bleach. However, when I was scrubbing away (which was one of the least fun things I could think of doing), I noticed a few things which seemed odd:

- foremost, I noticed there are these hard "deposits" on only the affected beams (I took a picture - They seem to be as hard as concrete, and they only chip off with a lot of effort with a screwdriver...on closer inspection, they even look sort of like a chunky concrete splash...particles lumped together, the flakes snap apart. Basically...they look very un-mold like (and don't come off at all when I scrub over them).

So, while I still assume we have mold, these deposits got me thinking that maybe it is just some sort of water leaching through the joists leaving these deposits...but i'm no expert, hence I am here Any ideas on what this could be?

Some more notes:

- there are just two joists affected and they are side by side.
- the joists run the length of our basement...backyard to front yard
- the (assumed) mold is white-ish, and when I scrub it with the bleach solution, it turns a muddy grey (and seems to be dirty like mud)
- our basement is always quite damp, but we've got a french drain with pump and all that good stuff

Anyways, just wanted to see if anyone had any ideas if this in indeed mold, and what the concrete-y deposits are. Thanks!
Sponsored Links
Old 06-12-05, 08:49 AM
Join Date: Dec 1999
Location: South Dakota
Posts: 3,140
Received 0 Votes on 0 Posts
Hard Basement Mold

The first thing that came into my mind while reading your question, was alcali mineral deposits. The look kind of like concrete, get real hard, turn kind of muddy looking when washed. They come with water leaching. Put some 100% bleachj on them. If they do not come right off, they are not mold. They are not a problem. Good Luck
Old 06-12-05, 09:14 AM
Thread Starter
Join Date: Mar 2003
Posts: 24
Received 0 Votes on 0 Posts
Thanks for the reply, Jack - going with what you mentioned about "If they do not come right off, they are not mold." I noticed that all the areas I had wiped down with bleach yesterday now just look like I have white-washed the joists. The white stuff didn't come off, like I imagined "killed mold" would have looked like.

Thanks again!

- tim
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

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: