View Full Version : Stucco or plaster directly to cement board?
WilliamChildress
Dec 14, 2007, 05:43 PM
Hello,
Can I apply stucco or plaster directly to cement board? (ie - without the use of a wire/fiber mesh) If so can I do it in one coat or do I have to use a base then finishing coat?
This is in a basement I am finishing.
Thank you
EIFS EXPERT
Jan 3, 2008, 05:08 PM
I just spent 30 minutes answering your post w/step by step instructions but it was never posted. Dag gone it.
So the quick answer is yes. Let me know if you need more info.
jyesdi
Jun 28, 2008, 12:34 AM
I just spent 30 minutes answering your post w/step by step instructions but it was never posted. Dag gone it.
So the quick answer is yes. let me know if you need more info.
Dear Mr. Eifs Expert or anyone else that knows
The original question back in January was:
Can I apply stucco or plaster directly to cement board? (ie - without the use of a wire/fiber mesh) If so can I do it in one coat or do I have to use a base then finishing coat?
This is in a basement I am finishing.
Let me add on to that. Can I apply a stucco directly over cement board designed for exterior use without the use of a Wire or Fiber Mesh and can I do it in one coat?
Any hel[ would be most appreciated
Thanks
EIFS EXPERT
Jun 28, 2008, 09:38 AM
Yes you can. Quickrete makes a fiber reinforcerd polymer modified stucco basecoat that can be applied to directly to the cement board without the need to embed fiber glass mesh. That's kind of the least expensive way to do it but it does work fine.
lpbreton
Jun 29, 2008, 01:51 PM
[QUOTE=EIFS EXPERT]I just spent 30 minutes answering your post w/step by step instructions but it was never posted. Dag gone it.
So the quick answer is yes. Let me know if you need more info.[/QUOT
Do I have to put metal corners when using cement board or can I just tape and stucco thanks,
Leo
EIFS EXPERT
Jun 29, 2008, 03:58 PM
You must use a 4.5 mil. Exterior grade fiberglass reinforcing mesh or the aluminum corner bead; otherwise the corner joint will split in 2 weeks.
Once the cement board is up you can either embed the mesh into the stucco mixture(minimum 4" on either side) or nail/screw the metal lath corner and apply the stucco. I would go with the mesh.
jyesdi
Jun 30, 2008, 02:46 AM
Yes you can. Quickrete makes a fiber reinforcerd polymer modified stucco basecoat that can be applied to directly to the cement board without the need to embed fiber glass mesh. That's kind of the least expensive way to do it but it does work fine.
Holy Cow... That was fast. I am impressed. I figured since the last question you posted on this thread was like 6 months ago, I was probably talking into a hole. Thanks for the quick response.
csangster
Feb 20, 2009, 10:13 PM
Yes you can. Quickrete makes a fiber reinforcerd polymer modified stucco basecoat that can be applied to directly to the cement board without the need to embed fiber glass mesh. That's kind of the least expensive way to do it but it does work fine.
EIFS EXPERT,
Quikcrete also makes a concrete adhesive that they promote as being a catalyst to help bond new stucco to old concrete/stucco/plaster.
Do you think this is sufficient?
I ask because I have a little different problem. My wife and I paid someone to mud/tape our drywall in our finished basement. There were two areas where we wanted stucco.
One is on an exposed 80 year old concrete foundation wall that was crumbling. I new I needed a bonding agent to hold everything together, but I was unaware of the catalyst to help bond the new stucco to the old concrete. Either way, it worked great.
The second area was on a radiantly heated wall that I covered with concrete board instead of drywall so I would have more thermal mass and it wouldn't break down. The handyman just troweled the stucco (Quikcrete finish coat white) directly on the concrete board without any prep/prime/adhesive. While I was waxing/polishing our newly stained concrete floors in the basement I bumped the radiantly heated wall and the stucco popped off the concrete board in a LARGE area (2ft radially away from the impact site). I didn't hit it that hard and it just erupted off the wall. Now I have to patch, and I would prefer to just put on the bonding agent then new stucco and move on. Do I have a problem waiting to happen if I don't rip off all the stucco the handyman put on and redo it myself?
Thanks,
Chris
toddd
Apr 5, 2011, 10:13 PM
Can I apply stucco color coat directly over hardie board
jchacone1
Jul 8, 2012, 09:00 PM
Well, we did a 5000 sqft house with plaster from Italy over the concrete board, this house is very tall and the chimneys go almost to 40', After the first winter ( Idaho ) we noticed the plaster getting patches mostly on the west side walls ( back of the house ) then by the summer, the plaster started to come off and right now, we are spending another 40 thousand dollars to redo with the concrete boards the entire exterior, it looks aweful and we tried to sue the company that sold us the plaster and guaranteed it ( Paintsandplasters.com ) to no avail. So, as far as I am concerned, I would not apply Stucco to a concrete board, because I believe the stucco needs something to adhere to other than the smooth wall.
plaster master
Jun 17, 2013, 11:49 PM
Hello My name is Michael Casas. I am The Plaster Master here in California. I am based out of Southern California. Los Angeles. I am a lath and plasterer... a dinosaur to this generation. Your problem is "freeze and thaw" and portland based mortars traditionally don't do well in these environments. Try a Hydraulic cement such as Rapid Set Stucco Mix over metal lath. You can use a cement board lathed with a woven wire... "stucco netting" or a diamond "lath" for a really good cladding.
I would welcome an engagement.
Michael Casas
The Plaste Master
Www.theplastermaster.biz.