Correct procedure for block?

[expat_returned]

Hi everyone, I am new to the site, and what a relief that there is a place where I can be pretty sure I am not being lied too!

I am doing up my house and have had some cowboy nightmares with the interior, but most of that is behind us, and now we are turning our attention to the outside. I would appreciate some feedback on a quote that has been given to me by a contractor to replace my broken concrete drive and front garden area with brickweave.

The total area is 100 m2, the existing drive is concrete about 2-3 inches thick, a good 25-30 m2 of the job is exsting lawned area.

The contractor has said he will remove the old driveway concrete, lay a new concrete sub-base three inches thick, then lay 50mm of sharp sand and then 60mm blocks. We spoke about drainage and dpc's and he seemed to know his stuff.

My question is does the 3 inch concrete sub-base and 50mm sharp sand layer and 60mm block sound like its the correct way to do it?

thanks,

[seanandruby]

totally wrong. He is using concrete sub base ( rigid )
And sand ( flexible ) for the bedding. It has to be rigid all the way, or flexible. sub base, whatever for a drive needs to be 100/150.

[GB_Groundworks]

did he mean crushed concrete if so it should be minimum of 100mm thats 4 inches well compacted, i.e 3 to 4 passes with a vibrating plate or a roller

if he means concrete, as in wet mix concrete then its a no no, there is very detailed information on the main page of this site. if you get a cup of tea and spend a few minutes reading it you will be in a much better place to feel confident about choosing the right contractor.

[expat_returned]

Time to put the kettle on, many thanks for the guidance.

[Pablo]

His concrete is too thin and the sand is too deep. You will get a better result if you used a 150mm + compacted stone base 30mm of sand then block. It'll be cheaper too. If you have soft clay then best to use a geotextile under the stone to spread the weight. You can lay on concrete but best if it was 100-150 mm thick with reinforcing mesh and a fin drain under the sand to prevent pumping of water logged sand.