Are these stucco cracks caused by structrual problems? (roof, window, heating)

[firsthomeowner]

Originally Posted by goodgal

Do you have hard coat stucco or the kind that is stucco with a thorolastic coating over the foam? You should have expansion joints above & below the windows. I would worry more about water seepng in the cracks than the aesthetics since wood is underneath.

Hi Goodal, I ever went to the construction site of my builder. They seems to put some waterproof stuff on the wall first then start to do the stucco coating. Does that mean the water would not damage much of the wood under the window? Thanks again.

[goodgal]

thorolastic is usually used to prevent hairline cracks from showing. It is an elastic type paint coating used on stucco. Do you have expansion joints above/below your windows? These are there to prevent the cracking. The waterproofing is a step all stucco houses have done during the process but make sure they flashed around your windows. If the wood is rotten or needs replacing in places I would make sure the flashing is there!

[firsthomeowner]

To be honest, I don't know whether or not the thorolastic paint was used by the builder. But I saw some recommendation from internet that the elastomeric paint or latex paint could be used to cover the cauk after filling the crack. Which paint should I use, thorolastic or elastomeric paint? Can I get them from Home Depot? Thanks again.

[goodgal]

thorolastic is an elastomeric paint. Most builder's supplies can order this for you and color match it. Make sure to shop the price as it isn't cheap. It should cover the hair line cracks. Make sure the stucco system is sealed with clear exterior caulk around windows. It is imperative water not find a way in or you will be replacing wood which is costly! Good luck!

[K'ledgeBldr]

By the looks of photos 1 & 2 (over doors/windows?) you have no drip cap/flashing over them. Which means you will have a moisture/water infiltration problem. Your only recourse at this time is to throughly inspect every year. Caulk/ re-caulk whenever you see any kind of separation. As far as the cracks- that's pretty typical. It's expansion and contraction of framing members. It usually appears in corners because you have opposing forces working there.

[firsthomeowner]

K'ledgeBldr, thanks a lot for your help. I did find this forum is a really nice place with so many kind people around to answer questions very quickly and professionally. I do learn a lot and hopefully would have a chance to help others in the future. I definitely will thoroughly inspect those cracks annually. BTW, you mentioned cauk. Could you pls tell me what kind cauk material I should use? A couple of days ago, I used DAP, 35 yrs, latex with silicone, exterior cauk. Does this work? Thanks again.

[K'ledgeBldr]

Originally Posted by firsthomeowner

Could you pls tell me what kind cauk material I should use? A couple of days ago, I used DAP, 35 yrs, latex with silicone, exterior cauk. Does this work? Thanks again.

Generally, for most H/O latex is the way to go- easy clean-up with soap and water. The silicone additive keeps caulk pliable longer. The main thing to remember is make sure it is paintable (some silicone caulks are not), that way you can "hide" the caulked up cracks with touch up painting.

[firsthomeowner]

KledgeBldr, thanks for your quick reply.

[firsthomeowner]

I read one post in house forum about the front load washer/drier on second floor. In that post, it was mentioned that the vibration of the FL washer could cause some problems to the joist of the floor (or ceiling to the first floor) and even some structural problem in the long term. I happened to have bought front load washer/drier and indeed it has some vibration issues though it's not that serious, such as jumping back and forth...But now, I start to think whether or not this could cause the stucco crack problem at the corner of the windows, which are just below the laundry room. Oh, BTW, I did talk with a friend who also has the front load washer/drier on the second floor. He also mentioned the stucco crack is at the same position as my windows. So, does that confirm the FL washer could be the culprit? Thanks a lot and any inputs are highly appreciated.

[K'ledgeBldr]

Originally Posted by firsthomeowner

So, does that confirm the FL washer could be the culprit?

Very highly unlikely. That's not going to create enough movement in the framing structure to create the cracks. But, can you imagine changing the moisture content of the framing by 20% and the forces it would create from the expansion or contraction?