Overhang on flag and brick steps

[wrathkeg]

Hi. I am planning some steps in the garden with flags on brick (along the lines described on http://www.pavingexpert.com/featur01.htm). The flag is 600x600x50mm, reclaimed from elsewhere in the garden. I see that there is a minimum recommended overhang for the tread of 25mm, but any views on a _maximum_ overhang in this situation? The reason I ask is that while the stable base (concrete) is well wide enough to support 550mm of bricks across the flag, it isn't really deep enough (and can't really be enlarged without a huge amount of hassle) so I'd like to make the overhang as large as reasonably possible.

Thanks,

wrathkeg

[lutonlagerlout]

50mm is max really
any more and it becomes a potential drama
LLL

[wrathkeg]

thanks for that. out of curiosity, is issue that with a bigger overhang the slab might crack? or tip up? both? something else?

[r896neo]

It's the danger of tipping it really. Mortar in its basic form does not adhere that well to pressed concrete in particular.

There are plenty of New fangled super jollop additives and performance mortars that will stick like crazy but your average mix provides more in the way of support than it does a good bond.

I myself have been educated by the aforementioned Lager lout as i previously used building sand for steps due to the extra grip it gives over grit sand but now i lay on grit with bonding additives. (SBR)

[wrathkeg]

makes sense -- actually that (tipping) was the reason I thought to ask in the first place. thanks for the tips re the mortar mixture.