Compacting is in itself a learning experience. Some areas became solid and didn't move at all, others still felt a bit squishing under foot. I found out this was simply due to the retained water in the clay getting pushed up and mixing with the MOT as I was compacting, making it slushy. However, as it was pushed up and out of the clay, once into the MOT mix it was able to evaporate more readily. Once this happened, the MOT hardened very quickly and I was ready to lay the slabs.
I used pre-mixed bedding mortar: sand and cement pre-bagged in the correct quantities. A bit more expensive than mixing your own but I wanted the proportions correct for my first go. You just add water and aim for a consistency of a thick sludge. You don't want it runny as they won't hold the slabs level.
I had to cut one row of slabs for some reason as they wouldn't follow the existing joints otherwise, even though they are the same slabs. For this I had to purchase an angle grinder with a blade suitable for cutting stone. Having never bought or used this tool before, I did a lot of research on line, watched videos etc. I also watched a lot of videos about laying slabs, whether or not you needed to 'butter' the back of slabs (which for concrete ones like these you don't).
The existing patio sloped towards the house but as the existing patio was already laid to a fall, all I had to do was ensure I laid each row level with the existing row.
At this point my worry was always that in a year's time, the slabs would settle and become uneven. I knew this would be down to how well the sub-base was prepared and that decision to lay down the membrane before the clay was completely dry was still playing in my mind.
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