Cementous based scratch/brown/topcoats aren't waterproof or even very water resistant. Its the underlayments, flashings/drainage planes that keep the wall structure dry. Concerning the block, if it wasn't sealed before topcoating, that is more than likely the problem. That's why out here they lath over block with underlayments, flashings, drainage planes to keep the block dry. Caulking will only be a temporary fix and will need periodic inspection/maintenence. You might consider a waterproofing topcoat or an elasomeric topcoat as being in Florida, you shouldn't have long extended periods of freezing that can allow moisture in and behind. Traditional stucco topcoats dont work well in freezing areas, okay in your neck of the woods.

An expansion (control) joint in stucco is a long narrow metal strip with a pleated fold at the centerline. The fold is all metal and caulking the exposed groove would serve no waterproofing purpose.

Where a metal control joint might leak is where it ends or crosses another control joint. At these locations caulk should have been placed behind the joints before the stucco was applied.

My builder told me it was probably the location where the vertical expansion joint met the horizontal one. There was not enough caulk there. So, does he have to rip that apart and put caulk and put stucco and paint. Is that the recommended fix?

Out here, expansion joints are installed after the underlayments and the cross joints lapped by way of tabbing where they meet. Not too many installers do this however as they typically just butt the joints. If installed before the underlayment, it would have to be carefully lapped by the underlayment and the use of self adhering tapes, which makes no sense. A leak can occur by sloppy underlayment installs where it is ripped or torn and not repaired allowing moisture to get in under the underlayment. A cheaper way to inspect would be to pull the sheetrock from the inside and remove the insulation in the area where suspect and see if the underlayment is intact if you have a finished garage. Attacking it from the exterior would be the second approach.

Horizontal expansion/control joints out here have weep holes similar to the weep screeding flashing at the base of the wall to allow moisture to run down and out, hence the reason to install over the underlayment/drainage plane.

I am not a building expert so let me try to explain what my builder told me. My house is two story. The first story is all concrete block. The blocks are laid, then every four feet concrete is pumped in for reinforcement. Then the cement mixture is applied. Textured top coat is applied. Primer is applied and lastly paint is applied. There is nothing else.

The problem is the joint between the second story and the first story. The second story is all wood frame. When the wood frame is laid on top of the concrete, it is a little bit recessed. There are 3 layers of plastic moisture barrier on the wood frame, then wire lath and then stucco. The stucco on top of the wood frame is a little bit thicker than the concrete block. The expansion joints are needed only in the wood frame. My house has vertical expansion joint on the second story and horizontal ones between the two stories. I am not 100% sure how the expansion joints were laid out before the stucco was applied. I can look through pictures I have.

My builder thinks that the water came down the vertical expansion joint and then at the junction between the vertical and horizontal, it found a pathway into the block and then ran down into the block and found its way into the interior. He said that caulking the vertical/horizontal joint would suffice but he would caulk all the joints everywhere in the house. I have given the link to this thread to my builder so he can read the comments himself. They have been very good to work with.

Sorry Bommai, I assumed you had framing on a block stem wall. Should have read more carefully about the first story being all block. The vertical joint where it meets the horizontal could be suspect if the underlayment/flashing was installed improperly, but as Macv points out, caulking the exposed area of the expansion joint topically isn't going to be the fix. The area of concern should probably be undone and inspected. Water intrusion can travel horizontal as well as down, so it's a tracing game.

With the framed wall being recessed but built out with the stucco to plane in with the topcoating on the block, a z-bar type flashing coinciding with a weep screed at the base of the frramed wall to allow moisture to run down and out over the topcoating of the block. The upper and lower walls would be seperated by this flashing technique, not a horizontal expansion/control joint.

You might find some useful info on the "Bad Stucco Gone Bad" site: http://www.badstucco.com/ Also, "Caulk is Cheap" is a good article explaining why modern building methods that rely on caulk are inferior to better methods using flashing, a drainage plane, etc. http://www.nashvillescene.com/2005-11-10/news/caulk-is-cheap/

I forwarded your postings to my builder. He is bringing the engineer and stucco guy on Tuesday and are going to break up that area to see what could be going there. Hopefully they get to the bottom of this.

Well. Here is an update. My builder showed me two products. One is the weep screed. It is a plastic thing that has solid plastic on the top side and one with holes on the bottom side. The bottom side goes on the concrete block and the top side goes on the wood frame. They are supposed to put tyvek over the top and wire lath and then stucco. My builder's stucco contractor incorrectly used a vertical expansion joint material that has holes on both sides as the horizontal expansion control joint. My builder is not giving me a clear direction and is asking me to choose. He said he prefers cauling the entire joint with silicone caulk and paint the house in about 9 months (to allow concrete to cure) paint with elastomeric paint. I would rather they tear up the stucco and fix the root cause. He says, that could damage the tyvek, etc. What should i do?

Bump. My builder says it is risky to cut open the stucco without cutting into the tyvek on the second story. The paper cut could cause more leaks! I still want them to do it. They want to just caulk and paint with elastomeric after a year. However, I have a nagging feeling that I should just ask him to fix it the real way.

The correct way to repair it would be to open it up and get either a "z" bar flashing with a perforated "j" chennel ( a type of weep screed) over that, or the weep screed that you mentioned, either one installed with the underlayment/lath/stucco coats over the flanges. Cutting the stucco it should be cut at a bevel,(angled up the wall), not all the way through and carefully cold chiseling the remaining so they dont disturb the underlayment. All along the leading edge of the saw cut, it should be broken away or chipped with a hammer randomly. This will insure that there will be no cracking along the saw cut edge or line after the scratch, brown, top coating is done. If they just leave the sharp edge of the saw cut and stucco to it, it will leave a crack the length of the saw cut. They need to install the proper drainage plane by use of getting the weep screed in there so it rolls off the underlayment of the wall and out and over the block. The elastomeric coating for the block is great, but caulking is only a temporary fix at best and will be a source of constant inspection and maintenance.

Thank you sierraeast. Are there any pictures online that you can point me to for the z-bar type flashing and the various type of weep screed. I think my builder made a mistake by building the wood frame second story slightly inset from the concrete block first story. I guess it needs to be slightly sticking out so that the water runs off. He has admitted the error and wants to fix it and give me guarantees but is apprehensive about opening it up. It is my job to convince him to do it. I am sure they are an honest builder but it will still be a nosebleed in public for them if they have to open up my house in public. I am pissed because we paid a lot of money (with upgrades) for this house and it is our first new house and the leak happened 2 weeks after we moved in (the house got certificate of occupancy only on march 3rd. I wonder why the city inspectors did not catch the mistake. They keep coming to do inspections every step of the way!

Hi Bommai, actually holding the framed wall in the thickness of the coats of stucco is correct so that the surfaces of both walls plane in even. That's why out here we use a z-bar flashing. Picture the "z" being inverted ,(or upside down),so that the upper back flange nails to the framed wall, goes out over the block, with the outside flange hanging down over the block. Then a perforated j-channel is held up 3/8" or so nailed to the framed wall above the flat or level section of the z-bar. Underlayment,lath, stucco coats go over the flanges nailed to the framed wall so that moisture runs off the underlayment, out the perforations of the j-channel, hits the z-bar which directs it out over the block. If they held the framed wall out flush to the block, it would have an overhang because of the thickness of the stucco coats and even with a weep screeding, unless they flashed the transition point framed wall to block, moisture could still seep between. I dont have the know how to post a drawing on this forum, but if you would like to e-mail me, I could take a digital of a drawing and e-mail it to you if you provide me an e-mail address to you or your builder. I dont know of any websites that show this method, but you could google framed wall to block wall transition and see if they instruct on different claddin methods, in your case, stucco.

I found this. It shows a wall to roof connect but if you scroll down to the illustration, you'll see the z-bar labeled and picture that going over your block,( the illustration shows it over the roof's step flashings.

Here is a link that might be useful: z-bar

Thanks sierraeast - I sent you an email through gardenweb and gave you my email address.

Just an update. My builder is coming tomorrow to start cutting into the stucco. Oh Boy. I hope they don't make the situation worse and it does not rain much!