Used this site when lying a small patio for a greenhouse base, back in October and it was very helpful. (Thanks)
I would be grateful on getting some comments on a patio we had laid for us in June last year by a builder who was recommended by a family member. This builder had built a very nice (looking at least) extension to their house. But never laid any patios for them...
We had a quote from the builder which included:
1. Digging a sub-base, to be filled with hardcore then whacked down.
2. Patio laid on sand and cement.
3. Pointed with mortar.
We proceeded...
Our house is a new build in Cambridgeshire, so not great quality soil, clay and very compacted. The builders put turf on the clay before we moved in and survived remarkably well, considering the quality of the soil underneath!
The builder began by removing the turf, revealing the vary hard, compacted soil underneath. He then decided that a sub-base was not required and said that he would add aggregate to his sand and cement wet mix, effectively laying the patio straight onto our soil with a concrete layer, rather than just sand and cement.
I found this page at the time (https://www.pavingexpert.com/faq_subbas ... 20required.) which states that sub-base is occasionally required, and trusted his judgement/expertise...
However, we have since had various cracking in the jointing mortar (enough to fit a coin into) and now various slabs have moved, rock, come loose. One slab on the edge of the patio originally came loose and he re-laid it (saying "I probably stepped on that one before it had cured") and now that slab has come loose again!
Looking back, I think he just wanted to cut corners for an easy life and now we are having to deal with a dodgy patio!
I've not since found any other sites that recommend using concrete and no sub-base so wondered what you all thought, if possible. Is concrete that much stronger that it would prevent settlement - I have my unknowledgeable doubts.
I'm considering getting a quote from a landscaper who laid another patio for us to come and look at it and get his opinion too, and a quote for lifting and re-doing it, which I will look to get covered in some way by the (lazy?) builder.
The way he laid the slabs was not a full bed, but rather a bunch of piles plonked quite close to each other. Some of the slabs sound hollow (movement/voids maybe?) and the way he pointed was to fill with sand first (to fill those voids maybe?) and then mortar over the top. Another lazy move to cut corners? Feels so, as some of the mortar that has come out is less than 10mm deep, when the slabs are 22mm deep.
He has blamed the cracks in the mortar because it was really hot when he laid it, but surely these are cracking because no solid foundation was laid?
Sorry for the long message. Looking for some experts advice please.
Thanks
