I just bought a 2015 Ford Focus, and I noticed these rectangular patches in the trunk. Are they supposed to be there?
Totally normal! Those are factory sound-deadening materials.
Jem said:
Totally normal! Those are factory sound-deadening materials.
Thank you!
Yep, it’s sound-deadening material. It adds density to the metal to reduce noise, not a patch or bad weld.
Freddie said:
Yep, it’s sound-deadening material. It adds density to the metal to reduce noise, not a patch or bad weld.
Thank you 
I might be wrong, but that looks like it could be mold, which definitely isn’t normal. I’d get that checked out.
Amari said:
I might be wrong, but that looks like it could be mold, which definitely isn’t normal. I’d get that checked out.
@Valen
Got it! Sorry, I thought you meant something else. Yeah, those rectangles look like factory material – maybe a bit dirty, but normal. If there’s mold, though, that’s worth addressing.
Amari said:
@Valen
Got it! Sorry, I thought you meant something else. Yeah, those rectangles look like factory material – maybe a bit dirty, but normal. If there’s mold, though, that’s worth addressing.
Sorry if I wasn’t clear – my English isn’t perfect! Yes, I was talking about the colored rectangles.
@Valen
No worries! I totally get you. From what I know, those are likely factory welds or soundproofing. I don’t own a Focus, though, so not 100% sure. But if it’s mold, that should get checked out.
Amari said:
@Valen
No worries! I totally get you. From what I know, those are likely factory welds or soundproofing. I don’t own a Focus, though, so not 100% sure. But if it’s mold, that should get checked out.
That’s factory sound-deadening material to reduce road noise. You’ll see it on door panels, under carpets, and around the fuel tank too.
@Heath
Wait, it’s not metal?
Amari said:
@Heath
Wait, it’s not metal?
Nope, it’s a type of asphalt material. Great for soundproofing.
Amari said:
@Heath
Wait, it’s not metal?
Nope, it’s a type of asphalt material. Great for soundproofing.
Well, you learn something new every day! Thanks!
Amari said:
@Valen
No worries! I totally get you. From what I know, those are likely factory welds or soundproofing. I don’t own a Focus, though, so not 100% sure. But if it’s mold, that should get checked out.
Thanks for clearing that up!
Those patches are fine, but definitely check for any mold or moisture around them.
It’s sound-deadening or sealant. If you need to remove it, it’s a tough job – requires freezing it, then breaking it off. As for mold, just give it a good clean with a wet vac and scrub.