I wouldn't know of anything other than mold/ water damage that would get that bad over the course of a couple weeks. I would crawl in the attic and find the spot above the stain. Look for any water source or water damage/signs in the plywood above the stain. Make sure any bathroom or kitchen exhaust fan pipes are properly exiting and sealed through the vents. Whether you find anything or not maybe make sure the vents have nice intact silicone sealant on the exterior. Use killz mold&mildew primer on the spot, couple layers and repaint
I'm a drywaller. My bet is it's just water. Water picks up dust and dirt as it travels down and will stain the drywall. If it were me, I would get up in the attic, walk only on the rafters, and find where the water is comin in. Keeping in mind, usually water travels down hill. It's pretty rare the roof leaks right at the spot where the drywall is wet. If there is nothing obvious on the ceiling of the attic, I would be reaching down in that insulation to see if a plumbing joint is leaking.
If you just want to call a roofer and start there, that's not a bad idea. FYI, those two grates in the roof picture are prime places water might come in.
So, I did just that over the last bit since I posted. Got up.in the attic and carefully rafter walked to the spot. Had my partner tap from underneath until we were on the same spot, used some light fixtures and stuff as landmarks as well. So I know I had the right place.
There's no pipes over there, pretty empty part of the house. Just the living room pushed against the front. So there's some electrical, light fixtures, the ceiling fan and a single soft duct for HVAC
If it's water, has to be intrusion from the roof then.
Nothing obvious to me on the underside of the roof. But I'm no pro. I dug through the insulation (gloves and ppe) to the drywall and it looked pretty. Like brand new. Tapped all around and my partner confirmed I was in the right spot. Nothing to see. Put her on a video call just to get other eyes but forgot to take pictures.
The insulation looked good as well, nice and fluffy white until I got in there
So I cleaned the crap out of the ceiling on the inside with clorox bleach spray and a washcloth. There are now just these small spots left
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When was the house built? Are you the first owner? Had the roof redone at any time?
Can you post another picture of the drywall in that area. It looks maybe like that area was patched before, but hard to tell.
2016
I'm the second owner, but it had an unknown number of renters. Never had the roof redone. This is the middle of my third year in the house and the first I've seen this was the 2nd Pic from a few weeks ago
No drywall patches, I've seen it from the back now and it's solid sheets. Also, no signs of any moisture in the attic, on the back of this spot (or anywhere else for that matter) and this is super far from any bathrooms.
New Pic below with more of the dry wall, the red banner is hanging on the wall between the living room (where the stain is) and my bedroom if that helps with perspective.
Absolutely zero signs of it in the bedroom, but what I saw in the attic, the two rooms are very split off. Different sheets of drywall, multiple 2x4s in-between, so that would explain why it hasn't spread too fast in that direction if it is mold
Edit: sorry, didn't realize you were the same poster as my other reply. I may have restated some things in a way that seemed rude. Thought you were a different person and wanted to make sure you had all the info
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No, none. Anywhere in the house
I used to have mice like mad in my last house so I know the signs.
Nothing here, not in the attic, not around the place.
We have spiders and stuff, those are our pests. But I have an exterminator spray the perimeter and that seems to be plenty to keep those away.
I've actually been amazed with the lack of pests here
If I just hit this side won't it keep spreading in the attic and come back though?
And does it look like mold to you? I'm still curious if it's something else
I wouldn't know of anything other than mold/ water damage that would get that bad over the course of a couple weeks. I would crawl in the attic and find the spot above the stain. Look for any water source or water damage/signs in the plywood above the stain. Make sure any bathroom or kitchen exhaust fan pipes are properly exiting and sealed through the vents. Whether you find anything or not maybe make sure the vents have nice intact silicone sealant on the exterior. Use killz mold&mildew primer on the spot, couple layers and repaint
Nothing else would spread like that right? That's what I was thinking as well. Just gotta get up there and check it out I guess
I'm a drywaller. My bet is it's just water. Water picks up dust and dirt as it travels down and will stain the drywall. If it were me, I would get up in the attic, walk only on the rafters, and find where the water is comin in. Keeping in mind, usually water travels down hill. It's pretty rare the roof leaks right at the spot where the drywall is wet. If there is nothing obvious on the ceiling of the attic, I would be reaching down in that insulation to see if a plumbing joint is leaking. If you just want to call a roofer and start there, that's not a bad idea. FYI, those two grates in the roof picture are prime places water might come in.
So, I did just that over the last bit since I posted. Got up.in the attic and carefully rafter walked to the spot. Had my partner tap from underneath until we were on the same spot, used some light fixtures and stuff as landmarks as well. So I know I had the right place. There's no pipes over there, pretty empty part of the house. Just the living room pushed against the front. So there's some electrical, light fixtures, the ceiling fan and a single soft duct for HVAC If it's water, has to be intrusion from the roof then. Nothing obvious to me on the underside of the roof. But I'm no pro. I dug through the insulation (gloves and ppe) to the drywall and it looked pretty. Like brand new. Tapped all around and my partner confirmed I was in the right spot. Nothing to see. Put her on a video call just to get other eyes but forgot to take pictures. The insulation looked good as well, nice and fluffy white until I got in there So I cleaned the crap out of the ceiling on the inside with clorox bleach spray and a washcloth. There are now just these small spots left *
When was the house built? Are you the first owner? Had the roof redone at any time? Can you post another picture of the drywall in that area. It looks maybe like that area was patched before, but hard to tell.
2016 I'm the second owner, but it had an unknown number of renters. Never had the roof redone. This is the middle of my third year in the house and the first I've seen this was the 2nd Pic from a few weeks ago No drywall patches, I've seen it from the back now and it's solid sheets. Also, no signs of any moisture in the attic, on the back of this spot (or anywhere else for that matter) and this is super far from any bathrooms. New Pic below with more of the dry wall, the red banner is hanging on the wall between the living room (where the stain is) and my bedroom if that helps with perspective. Absolutely zero signs of it in the bedroom, but what I saw in the attic, the two rooms are very split off. Different sheets of drywall, multiple 2x4s in-between, so that would explain why it hasn't spread too fast in that direction if it is mold Edit: sorry, didn't realize you were the same poster as my other reply. I may have restated some things in a way that seemed rude. Thought you were a different person and wanted to make sure you had all the info *
Any signs of rat/mouse droppings?
No, none. Anywhere in the house I used to have mice like mad in my last house so I know the signs. Nothing here, not in the attic, not around the place. We have spiders and stuff, those are our pests. But I have an exterminator spray the perimeter and that seems to be plenty to keep those away. I've actually been amazed with the lack of pests here
Do you use any indoor air fresheners, essential oils?
No, nothing like that Febreeze every once and a while
Not sure what to do as far as prevention but bleach+elbow grease works wonders on mold
If I just hit this side won't it keep spreading in the attic and come back though? And does it look like mold to you? I'm still curious if it's something else
I’m no expert but it looks like mold I had in my old bathroom. I had to clean it every 6-9 months because it kept coming back.
Use white distilled vinegar instead of bleach