[Bellringer]

Some cracks have recently developed in my stucco block house which is 23 years old. I have some stair-step cracks from settling on a corner but these are stable and have been there for years.

Recently, a new crack led me to discover an area where the stucco is applied over plywood. Withour removing the stucco I can't tell how big but from sounding it is approximately 18" square and starts at the top of the wall where the big crack is in the photo.

My questions are:
1. Should I break out all the stucco in the area and make a masonry repair of the wall before repairing the stucco?
2. Or, can an acceptable repair be made over the area without replacing the plywood?

I really am baffled by why there is this plywood area. These are tract homes built many at a time and in the same way so it is not something to be expected. I am not the original owner and was unaware of this area (since it didn't show then) when I purchased the home.

Thanks for any suggestions or ideas.
https://goo.gl/photos/M2mQUeUfQte3xHFy8

 

[jomama45]

I don't do any stucco work, it's just not common in this area, but how can you tell that there's plywood underneath? The step cracks below are a sure indicator of direct to block stucco.............

 

[Canarywood1]

The only time i've seen plywood used here is on a curved entry or window , everything else is solid block.