Wet or Dry Mix for Laying Patio Slabs and What Ratios to Use? Post your questions and get answers regarding all areas of drives, pathways and patios

[baron777]

I am laying slabs to make a patio area, its approx 15M square, and im not sure whether to use a wet or dry mix for the mortar bed.

As this is the first time ive done this, I am thinking the dry mix would be easier, but is it going to set properly, its only going to be for walking on.

I was going to do a ratio of 9:1 for sharp sand and cement for the dry mix, to a depth of 40-50mm is this ok? or should the ratio be less sand

And for the pointing, I was going to leave a 5mm gap between the slabs and then let them set for 24 hrs, and then do another mix of dry mortar, with ratio of 3:1 sand/cement, is this ok.

I am planning to measure the area, and use string and pegs to map out the area, and will be putting down 40mm of sub base (gravel and stones),

If I was to use a wet mix, what ratio should I use, and how much water, ive read that you should roll the mix into a ball and it should be soft but also hold together,

I would appreciate any tips,

Thanks

[neil-the-handyman]

Hello there Neil the Oxford handyman here,

The golden rule as far as slabbing or block paving goes is as follows;
Foot traffic - 75mm/for vehicles 150mm whackered (compressed) hardcore or type1, base. Followed by a sharp sand/cement (stronger the better - at least 6:1) screed. Moisten the mix so that if you grip it in your hand it just about maintains the shape and holds together.Using poles laid at the required depth into the screed and distanced apart so that a straight bit of timber can be dragged along them thus levelling the area between. Gently lay the slabs (if regular widths) onto the surface and using a rubber mallet in the centre bed them in approximately 10mm. Place your timber across the entire course and strike with a mallet to ensure they are in line with each other. As you progress repeat this in all directions. This prevents water pooling in any unintentional dips and troughs. A 1:40 fall sloping away from the building or leading to a soak away is essential.
Ensure the desired spacing between the slabs is maintained. Allow at least 24 hours for the screed to set (the longer the better!). Test one first before you go all Strictly on it!

Hope this helps.
Good luck in your endeavours