Home>Discussions>EXTERIORS>cultured stone exterior.....needs mortar?
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queenie
cultured stone exterior.....needs mortar?
queenie

Sixty year old small, slab foundation, stucco house, single story. Nine years ago we had cultured stone put half way up the front, over stucco, and all the way up the brick chimney (which is in the front of the house.)

There are a few hair line cracks in some of the stones and between the stones, (both horizontal and vertical,) and a few gaps between the stones about 3/4 inches deep.

Should I be concerned? Do I need to find a mason? Does this stuff require maintenance?

Clarence
Re: cultured stone exterior.....needs mortar?
Clarence

Could be a number of problems.
The stone was added over existing stucco , you may not have a good bond between the stucco face & the stone mortar.
Weight was added causing stress in the lower area of the stucco.
Water entry at the top where the stone meets the stucco was it flashed or just mortared to the stucco?
I would say you have moisture on the face of the stucco behind the stone causing effiorescence this will cause the stone to seperate from the stucco ( Detach ).
I normally estimate something applied over stucco will fail in about 15 years you have about 6 years before a major problem of failure.
Do you have any white stains ( Effiorescence ) on the face of the stone this would indicate a water problem?

dj1
Re: cultured stone exterior.....needs mortar?
dj1

The mistake was to apply the stones on the stucco.

The cracks and gaps will most certainly grow, to the point that you will have to re-do the job. How long will it take? it's anyone's guess.

queenie
Re: cultured stone exterior.....needs mortar?
queenie

Thanks for your ides, even though they are pretty gloomy! None of the stones seem loose, the don't move or pull away, no efflorescence.

What if it is just the normal settling, moving, of a old slab foundation house. Can't these just be the "normal" cracks that happen with house moving, settling. Like the "normal" cracks that appear on the inside of my house, in the sheet rock, every 10 years or so. (NOT in areas that indicate serious support issues.)

Can a mason just fill in the joints and cracks, just like I caulk and paint over the occasional inside cracks?

Anyway I miss counted, it has been about 10 years since the cultured stone was put up.

If the stones are secure to the stucco and no water damage....isn't just a re-mortaring, patching a valid option?

Mastercarpentry
Re: cultured stone exterior.....needs mortar?
Mastercarpentry

Cultured stone, unlike real stone or brick, is not meant to be self-supporting- it has to have it's weight carried by something behind it to which it attaches. So if that lath or backing moves or fails, the cultured stone goes with it. A lot of cultured stone is weak and brittle from the start, especially in the usual cheaper grades. Plus most of it cannot be sealed and warranties will be voided if you apply anything over it or even use common chemicals or strong detergents to clean it. Check with the manufacturer before doing anything.

Now for the repairs- yes, you can re-mortar it, re-point the mortar, and replace broken or cracked stones. Just use the same mix that it was built with. It is not exactly waterproof and wasn't intended to serve that function as you might think; rather it is to protect against physical damage for what's underneath it. So you really don't need to repair it for other than aesthetic reasons unless stones are becoming loose or have detached completely. I would do something with wider cracks to help keep as much water out as they can do for you; that will also help maintain it's support structure underneath for as long as is possible.

This can be a good product when used and installed properly, but it is not what most people seem to think it is and far too many installations are not done well at all. People love the look and it's very popular but IMHO it's a bad answer in search of a question which never existed. Real stone made by nature is the way to go and you can use it to replicate the same look. It will cost a lot more because it is worth it, it has a history of success as long as history has existed, and you cannot really improve on something like that.

Phil

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