Suds or not? - Is this a viable construction

[Tony McC]

An old friend resurfaces via email. He's a landscaper who does the occasional bit of paving, but knows his limits. He thought this would interest me.....

A contractor has recommended a flagstone laying method - pedestrian only

- type 3 sub-base, 100mm
- continuous 70mm wet mortar bed
- flagstones with a porous resin pointing.

AND pre-pointing he makes holes in the wet bed with a metal rod.

So, he says the water percolates through the pointing - down the holes and through the type 3 subbase(no finings) Voila! So.... he says SUDS compliant

...if it had come in from A.N.Other, I'd have marked it as a wind-up, but I know this guy, so I've no doubt this methodology is being suggested as genuine.

To me, it seems ridiculous. If you want a suds-compliant flagstone pavement, lay on trass/no-fines bedding. Why would you spend all that time making holes you *know* are going to block up with litter, fag ends and general detritus?

What do the rest of yous think?

[lutonlagerlout]

make no sense to me
easier and better to use the same technique with type 1 and a 40mm *cement * bed and then use natural falls to grass or linear drains
if only there was a website with that information :;):
LLL

[sy76uk]

If he's putting the holes in the mortar bed under the joint in the paving then filling the joint with a permeable jointing compound it could work.
Not sure how well though.
It would be similar to laying permeable block paving on a pecked tarmac sub base.

[London Stone Paving]

It may work for a very limited amount of time but would be rendered completely ineffective in a matter of weeks.

Remember reading Tony's articles on soak away's a few years back and how they are doomed to failure. In this case the failure would also happen but a lot quicker (This is where we miss Carberry and his brilliant skill of locating any article/post ever submitted on Paving Expert)