Jointing slabs

[deuce22]

Hi.

About 3 years ago I had someone lay slabs for my drive. Its about 3m wide by 30m long.

About 6 months ago I noticed that quite a few at the front had become loose. It was an area of around 20m2, so I decided to take them up and re-lay them.

He had laid them on cement, but instead of setting them on a complete bed they were in blobs, one in each corner and one in the middle.

I have now laid them on a complete bed of cement and they are fine. What I now need to do is joint the whole area, because they were not done when first laid. I bought a point master jointing tool to do the job, but someone told me to just mix sand and cement and use it dry.

Which is the best way to go.

Thanks.

 

[TwoTrowels]

I've used the point master and reckon it's pretty good - you'll need a dry day and don't fill more joints than you can safely iron up in good time as once the joint is filled you need to leave it to firm right up for best results. Another way I also use is to make your pointing gear just damp like floor screed then iron it in hard, really push it right in the joint as hard as you can and then finish with the iron as usual, goes rock hard with zero staining - I usually use a 4:1 mix with building sand or building sand with the addition of 1 part washed (plastering) sand.

Forget the sweep in dry stuff method, it never lasts in my experience.

 

[r896neo]

Trowels advice is spot on. Personally i use plastering sand 4:1 as i find it holds less water and so can be mixed a touch damper and still not stain. Also gives a harder joint.

 

[deuce22]

Thanks both.

I will definitely use that tool and the materials and mix you advise.

I'm fed up of having to go over other people's (so called builders) work and just want to get it done right first time.

 

[r896neo]

If using the gun maybe go with building sand. A few large rogue grains that you get in plastering sand can clog it up occasionally. Experiment with the mix consistancy a bit.