Posted: Fri Sep 10, 2010 1:47 pm
I wanted to get a little advice on the final laying of the flags (600x600 textured concrete) for my patio. It will NOT have any vehicle traffic just feet and tables.
There is a two brick high retaining wall for the foundations - the slabs will just overhang.
So far the ground had a skim taken off and what remained is fairly solid and had not been touched for 20,30,40,50 years. About 100 to 120mm of MOT type1 was applied and compacted and then a semi-dry mix was added at around 75mm deep. This has now gone off and is fairly solid.
I am planning to lay the flags on a mortar mix probably using sharp sand. Different advice has suggested sharp or building or mix. I have also had advice on the mix; 10:1, 6:1, 4:1 and 3:1 as well as thickness. Some as thick as 60 or 70mm and some as low as 10mm.
Which sand would you advise and which sand:cement ratio?
What thickness too? It will be a full bed (or as near as possible) with a slope towards the garden (away from the house).
Also, is it necessary to leave a small gap against the house - there is a DPC against the house wall and the finished level is 150mm below DPC.
Thanks in advance
There is a two brick high retaining wall for the foundations - the slabs will just overhang.
So far the ground had a skim taken off and what remained is fairly solid and had not been touched for 20,30,40,50 years. About 100 to 120mm of MOT type1 was applied and compacted and then a semi-dry mix was added at around 75mm deep. This has now gone off and is fairly solid.
I am planning to lay the flags on a mortar mix probably using sharp sand. Different advice has suggested sharp or building or mix. I have also had advice on the mix; 10:1, 6:1, 4:1 and 3:1 as well as thickness. Some as thick as 60 or 70mm and some as low as 10mm.
Which sand would you advise and which sand:cement ratio?
What thickness too? It will be a full bed (or as near as possible) with a slope towards the garden (away from the house).
Also, is it necessary to leave a small gap against the house - there is a DPC against the house wall and the finished level is 150mm below DPC.
Thanks in advance