Block paving membrane. conflicting advice

[Ltnman]

There is a Marshalls manufactures youtube video about how to lay block paving and they mention how important it is to lay a membrane down to stop the hardcore sinking into the subsoil due to particle migration yet some of their approved installers say it isn't necessary. Why can't everyone sing from the same hymn sheet? So who is correct Marshalls or some of their installers as I need to pick one.

 

[noseall]

Depends on the substrate. Depends what membrane you are referring to.

The geotex road type membranes are specifically for heavy/frequent traffic loads and soft or 'pocketed' substrates i.e. clay etc.

It is unlikely for them to be necessary in a lot of domestic situations, but can be a practical solution to some unusual ground conditions.

 

[conny]

When my block paving was laid a few years back the old lawn was dug out and lowered by about 6". This was infilled with hardcore well rammed down with a vibrating wacker plate. A layer of 10mm gravel was then put down and also wacked solid. After this a breathable membrane was laid to allow rain moisture to pass through and then a bed of 2" compacted sand laid before the blocks were fitted. These were then in-filled with a very fine dry sand. I was told the membrane was to help prevent weed growth, which it seemed to do, but you will still get moss in the joints because of blown seeds. This is easily controlled with a wire brush type of tool on a long broom handle.

 

[skhudy]

After reading http://www.pavingexpert.com/faqmembr.htm I didn't use membrane when I did my drive. Put in a decent sub base compacting between layers and a polyeurothane finish. Neighbours is showing signs of dips and weeds, there's was done before mine although unsure they had the membrane. I do know they only took of a few inches and hardly used any sub-base

 

[skhudy]

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