Having spent ages worrying about the lack of depth of some of my drains, I am following advice and haunching with concrete. Some parts of the drain once haunched give me no opportunity to add sub base in fact I have only managed to coverr with about 50mm of concrete in parts. I have added subase along the drive up to the concreted section and can now get moving with adding the paving blocks. What I have is a ST1 sub base bordering a concrete slab covering the drains. Will water tend to wash the bedding sand from under the blocks that sit on the concrete? Would it be advisable to add a shovel of cement to the bedding sand for blocks over the concrete?
Cheers in anticipation
Andi
Block paving onto concrete - Preventing bedding sand washing away
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Tony McC
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No. No - no no - no no no no!!!! Never, ever add cement or lime or any other hydralic binder to the laying course material of a flexible pavement. Never. Ever. It's just about the worst thing you can do!
If your edge courses are sound, robust and properly laid, there is *nowhere* for the laying course to run. If you're worried about "Trickle Down", use a separation membrane, such as Terram BuildA or LoTrack.
If your edge courses are sound, robust and properly laid, there is *nowhere* for the laying course to run. If you're worried about "Trickle Down", use a separation membrane, such as Terram BuildA or LoTrack.
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