Cracks in stone veneer

Any ideas on what may have caused the cracking in the stone veneer on this home? The veneer appears to have been installed over brownstone - a popular material here in the city in the mid 1800’s through early 1900’s. The brownstone itself is has a tendency to decay and there was evidence of decay/scaling on some of the exposed brownstone.

I’m thinking the stone veneer was installed to cover the decaying brownstone instead of repairing or refinishing the original stone. Could the decaying brownstone also caused the veneer to loosen, crack and fall off or is there something else?

Hard to answer exact mechanism at play here from those few pictures but the short answer is yes along with the veneer attached directly in that way totally alters the original design function of any flashing though I am sure there is none and interferes with evaporation.
I might add we are talking what? over 100 years old here.

Not bad if you think about it.
Just recommend a mason look at it and wash your hands.

If it is installed over the stoop it could be just movement .

I am going to point to several factors that come to my attention.
I myself have never covered brown-stone. By looking at the materials around the window opening I see problems at work for years.
You have the caulking. It looks bituminous caulk ‘‘cheap’’ and not for windows and old and lots applied.,meaning it did not work ''and more.
The iron work (iron frames) and windows guards.
That material expands and contracts and are LARGE in size giving plenty of movement. Masonry applied the facade will not and is not meant to expand to that degree.
To me a home that maintenance was not thought out properly.
Its moisture and movement at work.

I am also going to post that covering brown-stone in ‘‘foe stone- to me’’ is a cheap fix and will not work every time unless well thought out.
Brown stone will not have a set pattern as brick and is much larger in size when being applied. so the off set for bonding well also be different.
The bonding lines will be longer and if there is movement in the brown-stone the’’ foe stone’’ well have long cracks appear sometimes. as they do here above the veranda.
I hope I am making myself understood.
It is not suitable nor comparable material for brown-stone and will have a limited life.20 years,
as compared to brownstone 100-200 plus if properly maintained.
That is my opinion.

I agree, appears you have both here.

Anyone have an idea how that stuff was attached.
Looks like they just troweled on masonry and stuck it up.
The expansion issue makes a lot of sense.

That’s how I see it = moisture/movement = cracks.

You have it in a nut shell BOB.
Like ceramic tiles. many types of bonding materials ,different grade for different surfaces.
There are different end caps corners.
This job would have had a better chance of longevity if 2 things were different.
1> being the backing could have been more elastic using add mix…
2> the job would have been waterproofed after it cured.
Moisture would not penetrate into the brown stone allowing movement.
I am being hypothetical here for I have never done foe veneer on brown stone.
Cement board and manufactured insulation for the purpose of veneer.

Wish Marcel was up and about:)
Never seen stone covered with stone like that yet and this could be an education.

I think he logged off an hour ago.Marcel
I have never seen this before and quoted it.
I would have done the job differently.
The longevity would have been tippled.
I would have done a long and full thought inspection before I made any decision.
3 days of investigation on materials etc.

Two forces at work.
If the mortar is weaker than the stone, cracks usually develop first along the mortar joints. The opposite is also true. This conditions shows cracking both in mortar joints and in stone.
The implication is movement of the substrate which is the brownstone to which the newer stone veneer is adhered. I’d guess two things are happening.
First… general substrate movement, possibly caused by foundation movement, is causing the veneer to crack along its weakest plane… the mortar joints.
In some places where the veneer bridges joints in the underlying brownstone, the bond between veneer and the brownstone is strong enough to telegraph failures (cracks) in the underlying brownstone mortarlines to the stone itself.

Do we have any idea how long the veneer has been there.
Anyone see it done this way before?

This should be close to the home in the photo or at least give example.
Most of the movement Kenton I see is being caused from the iron frams and window guards. I have tried to blow up photo’s but I can not but will learn shortly.
There is usually window elements in brownstone and look were the cracking is.
To me it is many combination’s of problems .
I can not say about foundation for this home part of a row house if I am not mistaken. Look at windows have been clad with tin-work to hide something.
Even the mortar and foe stone (false stone) has covered over elements of the wood and window trim.
Do not look at this as brick work it is thin pieces of cast cement made to look like stone.2 inches thick at the thickest and light for add mixes to aggregate to give lightness to most products I used.
Cracking up joints will be from backing element.

Thanks guys for all your input. I am in agreement about the moisture and movement comments, and will include comments along that line in my report.