Paving Slabs Joints

[joec1985]

Hi I just had a relatively small patio area paved with riven flags. The chap who did it has left me some kiln dried sand for the joints. My question is do I wash the flags first as there is a lot of dirt and mortar residue on them from the installation before I sweep in the kiln? Also do I dry sweep it or do the joints need to be wet?

Thanks

 

[r896neo]

Has he jointed them already and left you extra to top it up after cleaning? If he hasn't jointed them at all tell him to come and finish his job.

It must be really dry to joint with kiln dry sand. At this time of year that's difficult. You want to sweep it in after 2/3 dry days in a row.

It can be put in wet as a slurry but it's messy and difficult

 

[Ian H]

And it would wash out of anything but a tiny gap wouldn't it?

 

[r896neo]

Don't really know what you mean ian? The water is used to to help wash the sand down into the joints.

 

[Doggit]

Dried kiln sand is for settling in the small paving bricks, not for paving slabs, as it'll allow the weeds to grow.

This is what you need to look for - hence why your builder left you the cheaper alternative for you to do it yourself.

But yes, wash and clean the area before you apply the jointing stuff - again, something he should have done.

 

[r896neo]

Kiln dried sand is often used on small format flags like 450x450 or smaller. It's a perfectly acceptable joint for 1-2mm joints when using flexible bedding like compacted screeded sand.

A rigid flag laid on sand and cement and jointed with mortar is Superior and require less maintenance but the are millions of square metres laid flexible and jointed with kds around the country. For 400x400 flags it's more common

 

[Ian H]

Don't really know what you mean ian? The water is used to to help wash the sand down into the joints.

I was thinking kiln dried would be pointless on anything other than a tiny joint, like block paving rather than slabs.

 

[r896neo]

His flags have been laid tight jointed with 1-2mm joints. Kiln dried sand as you suggest is no good for joints larger than about 4mm