Hello all - I'm mudding the drywall in my garage. I used the normal
paper tape and it seemed to go up OK. Last night I put on the first
coat of mud over the tape. For the most part it looks OK, but in a few
places the mud is cracking slightly. Most of the cracks are a 1/4" or
First, any idea why this happened? I know people will say I put the
mud on too thick, but I don't think so. I tested the thickness of my
mud as I was putting it up and it was around 1/16".
Second, can I put my second coat of mud over these small cracks or do I
need to remove it and start over?
Probably thicker than you think. Only time in hundreds I've ever had
cracking it was due to too heavy of an application. Better to use 3
thin coats than heavy glopping ones that you end up sanding for hours.
Sand lightly between coats and it doesn't hurt to cut the compound a
little with water to thin slightly and make it more workable.
The cracks are almost assuredly from too thick of an application and/or
the mud drying too quickly. Not sure where you're located, but higher
humidity in the summer usually means it dries more slowly.
I don't see how a 1/16" thick application could possibly have 1/4"
cracks. There's something wrong there. Normally with small cracks you
can just cover them with a thinner conistency top coat and they'll get
filled in. If you can eliminate any other causes, such as contaminated
compound, and the cracked compound is well adhered, then just go ahead
and top coat.
You also might have another problem that you're not yet aware of. If
you're having drying problems, it's possible that the paper tape is not
well adhered. It'll look okay, but it will bubble down the road.
Before you put any more effort into it, make sure that what you have is
up to snuff before proceeding.
If this is the first coat, I wouldn't worry.
Sand and continue. If the next coat cracks, then you can start to be
I mudded up some 2x3" drywall holes and the first layer always cracked
baddly. It is expected when you have 1" of solid mud. I just sand and
continue with normal. The second coat usually goes on without a
Thought I would post a follow-up.
To answer a few questions, yes, the cracks are a 1/4" long, not wide.
And when I said "first coat", I meant the coat after the tape was up.
Is that considered to be the second coat?
The source of my problem was the mud. I was using some left-over junk
from my father-in-law that just wasn't cutting it. The mud even
smelled a little odd. After buying new mud, mixing it properly, and
putting on another coat, it looks fine. I just hope those cracks
underneath don't come back to haunt me.
cant_have_my email@example.com wrote:
The mud 'soured'. Good move on the fresh stuff. Apply it as I
explained earlier (thin coats) and the cracks will fill. You shouldn't
have further problems unless you apply it too heavy.
Thanks for the update. Most don't bother.
Just sand out the cracks before putting on the next coat, otherwise
you'll end up with voids or weak bonding between layers. If it's
really hot/dry in your garage, the cracking might be due to too rapid
drying. If that's the case, water down the mud slightly (and stir
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.