New Patio problem

[parker13]

Had a patio laid about three weeks ago, last night I noticed all the slabs are loose, they can be lifted up, they are on a one to four mix, yellow building sand, the slabs were called natural limestone but are more like slate, They haven't been pointed yet, Do they all need relaying or will the pointing hold them in place?, must say I'm kinda worried about this.

 

[MH]

I would say they have been laid when the ground it too wet or not enough hardcore. When we got ours laid, we had 4 -8 inches of 10mm hardcore laid first then wackered down, then the slabs were laid on that with a 4:1 mix of wet mortar and bedded on that.

 

[parker13]

I whacked it then they were laid on a wet mix, thinking the frost may of got to it.

 

[silverdale]

If frost has got to it they will have to be relaid again.

 

[Rumpelstiltskin.]

Temp for cement is min 3 degrees and rising.
Anything else and it will crumble.

 

[willin]

Had a patio laid about three weeks ago, last night I noticed all the slabs are loose, they can be lifted up, they are on a one to four mix, yellow building sand, the slabs were called natural limestone but are more like slate, They haven't been pointed yet, Do they all need relaying or will the pointing hold them in place?, must say I'm kinda worried about this.

One in four is a strong mix for paving, you should be using coarse sand, if you lift a slab is the mortar hard ? it would have to be quite cold to penetrate to the bedding. you may get away with pointing done properly if It's just the surface of the bedding .

 

[baron]

four and one three sharpe one builders sand one cement make consistancy stand up when tipped off trowel worked for me.

 

[Him Her]

Three weeks ago was probs not the best time to lay - the frost may have done the damage. If it's cold you could try a number of things including using warm water in the mix or a low temperature mix - check out the local builders merchants for suggestions...

 

[Oily]

When I use to lay flags we used a bed of fine ash because it doesn't hold water like sand so it doesnt freeze etc.Never liked bedding flags on cement although each to their own