Membranes
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84-1093879876
I am about to lay a 125mm sub base direct onto clay prior to block paving and have been advised to lay a (weed prevention) membrane under the hardcore first. I am unsure as to whether this would have any benefit. A colleague said he has just had his drive block paved and a similar type of membrane was laid between the sub base and the sand top dressing?
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84-1093879876
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84-1093879891
Good idea! :)
There's a subtle difference between 'weed membranes' and geo-sheets. The former are intended to keep out the dandelions and the like from gravelled areas, while the latter are a structural layer performing an important function within a pavement. You might use a geo-sheet at the boundary between the sub-grade and sub-base if there was a problem with the condition of the ground, but there is rarely any need to install a weed membrane beneath a block pavement that has a 100mm sub-base. The one exception is when there are pernicious weeds, such as Equisetum spp (Mares Tails) or Polygonum spp(Japanese Knotweed) and even then I'd much rather specify a geo sheet, on grounds of inherent strength, than a weed membrane.
99% (roughly) of weeds can not grow through a properly constructed block pavement, but even a weed membrane will not stop them growing into a block pavement, anchoring themselves in the sand-filled joints.
Weed membranes are, in almost every case, an utter wate of time and money when used beneath block paved residential drives and patios.
There's a subtle difference between 'weed membranes' and geo-sheets. The former are intended to keep out the dandelions and the like from gravelled areas, while the latter are a structural layer performing an important function within a pavement. You might use a geo-sheet at the boundary between the sub-grade and sub-base if there was a problem with the condition of the ground, but there is rarely any need to install a weed membrane beneath a block pavement that has a 100mm sub-base. The one exception is when there are pernicious weeds, such as Equisetum spp (Mares Tails) or Polygonum spp(Japanese Knotweed) and even then I'd much rather specify a geo sheet, on grounds of inherent strength, than a weed membrane.
99% (roughly) of weeds can not grow through a properly constructed block pavement, but even a weed membrane will not stop them growing into a block pavement, anchoring themselves in the sand-filled joints.
Weed membranes are, in almost every case, an utter wate of time and money when used beneath block paved residential drives and patios.