New patio pointing breaking up

[alwaysproblems]

Hi,

I had a new indian sandtone patio put down about 3-4 weeks ago.

It was set on a mortar bed but after a short time it looks like the pointing has failed completely.

One of the slabs on the end can be easily lifted out of place.

There is movement in a few slabs.

I have attached some pictures.

Any ideas what caused the failure and how to fix?

Cheers
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[r896neo]

rocking slabs have been inncorectly laid or perhaps walked on to early after laying. There is no fix other than to lift and relay the rocking slabs.

Being able to lift flags off the bedding mortar is not in itself a problem.

The pointing looks like it was too dry or perhaps the very high temperatures have made it crumbly as it didn't hydrate properly and it wasn't kept damp after being installed.

On very warm days the flags need to be pre-soaked and pointing needs to be misted to keep it from drying out too fast

Again no fix for this other than to rake/ grind it out and re-do.

 

[WabbitPoo]

Being able to lift flags off the bedding mortar is not in itself a problem.

Huh?

But as said, get the guy back to do it again (or you, if it was you who laid them!)

 

[r896neo]

A flag laid properly on a full bed of mortar with no voids does not need to be strongly stuck to the bedding. There is no lifting or lateral force on a flag once its pointed.

In my opinion.

Personally i use sbr in the mix to aid adhesion as a belt and braces approach but i don't think there is an issue with flags being very weakly adheared to the bedding