Replies

1. 
   DanH | Feb 13, 2010 11:33pm | #1

   The answer is going to depend on which of the several types of "stucco" he has. "Older", in this case, would mean prior to about 1970 or so, when stucco was stucco. Since then a number of stucco-like finishes have come (and in some cases gone).

2. 
   popawheelie | Feb 14, 2010 05:27pm | #2

   I grew up where a lot of homes were (old) stuccoed.

   After a certain amount of time the stucco starts to deteriate.

   So they came up with the elastomeric paint as a less exspensive way to "fix" the problem.

   There are a lot of older homes with this probelm so it started a whole trade/service industry.

   Since the probelm is on the south and west sides of the house I would guess it was sun related.

   If it is real hot and the sun beats down on the stucco while it is curring, it can cause problems.

   I've seen companies shade the stucco by hanging something on the outside of the scafolding.

   Where I came from, in So Cal, the houses had plywood under the stucco for sheer stregnth. So structual is probably out. What's under the stucco?

   In areas where stucco is used a lot the contractors know how to work with it. The crews do as well.

   Maybe in the north east they did have enough exsperience.

   I'm no expert. just some things I've seen.

3. 
   MarkCadioli | Feb 14, 2010 07:59pm | #3

   Ray

   As one of the posters here pointed out the south and west sides cracking point to the possible cause of the problem. Stucco is ridgid and assuming it is not an underlying structural issue ( position of cracks may give an indication a to whether or not this is the case) it is possible that the placement of control joints will aliveate the problem.

   Ideally I'd place them vertically at window/ door openings, cut them with a diamond blade then caulk with a good polyurethane ( sikaflex or something similar ). Do this before attemting any remedial work to the existing cracks.

   regards

   Mark

1. 
   popawheelie | Feb 14, 2010 09:44pm | #4

   Mark made a good point. I like control joints in materials that need them. They are overlooked a lot of the time.

   But... ;^ ) I've seen large expanses of stucco with no control joints and no cracks.

   Maybe it was a thicker, higher quality, more flexible stucco.

   I don't know.

   If I was putting stucco on a building I'd make sure it was done right because taking it off is a major pain.

4. 
   SamT | Feb 15, 2010 02:28am | #5

   rdon,
   Can't tell without
   rdon,

   Can't tell without seeing.

   Look for bad vapor barriors.

   Wind driven water/moisture.

   Most likely reasons are freeze thaw, structural movement, and bad stucco.

   Freeze thaw tends to spall more than crack.

   Structural cracks tend to be longer than lack of cure cracks, which tend to be spider webby.

   Primary cause of bad stucco is not fully curing between scratch and brown coats.

   Good stucco is kept damp for an absolute minimum of 7 days after scratch coat and after brown coat. Two weeks is better, but real careful pros cure them for 28 days.

   South and west sides tell me that maybe those dried out too much for a good cure.

   SamT

   MS Excel for Contractors

1. 
   Henley | Feb 15, 2010 04:51pm | #6

   To the OP (not sure if this is addressed to him or not).

   No one can tell from here with out pictures.

   Here in the North East water is the usual suspect. This being

   the extreme beginning of spring you will soon have plenty of

   opportunities to observe the walls in question.

   Look for the wet area to coincide with the cracks.

   Next as the loose stuff is removed for repair look for signs

   of water penetration, vapor barrier situations etc.

   I would venture to guess that if it had been a poor stucco application, it would have resulted in a more catastrophic

   failure then such localized yearly cracking.

   Could be structural, but then there should be other tell tale

   signs in the building.

   Look for the water.

5. 
   Jeff_Clarke | Feb 19, 2010 07:50am | #7

   I highly recommend reviewing the situation with a Conproco rep -

   http://www.conproco.com/prodcolorguide.php

   I've just finished a project with the Comprolastic - it's a really good coating product.

   http://www.conproco.com/ConproLastic.htm

   Jeff

6. 
   IdahoDon | Feb 19, 2010 03:39pm | #8

   Keep in mind that three coat stucco is pourous and while it sheds most water is not the water barrier--that's underneith.  Sometimes too much focus is on hairline cracks.   It's like a bathroom tile job--most water is shed by the tile and grout but the tile and grout are not stopping some moisture from passing through--they don't have to.

   If you put a coating over the stucco you now trap any moisture that gets behind the stucco and can't evaporate out.  You end up with the same issues that synthetic stucco has--if you do it you need to do it really well so no water can get behind.   You also have now changed how the wall breathes--no longer can moisture that makes it's way into the wall pass through to the exterior--it is held in.  If you have situations where the exterior gets cool the moisture will condense there and can't come out until it works it's way back into the house.

   Yes the flexible coatings for stucco do work and expand and contract to keep cracks from reappearing, but in solving that mostly cosmetic issue there can be concequenses much more harmful to the house.