Knowing when to cut flag due to a change in plane

[Mikey_C]

[Mikey_C]

i'm trying to pave the above area in a random pattern Indian sandstone. either side of the raised bed (sleeper) has drainage i.e. away from the house. i was planning on coming away level from the house in the middle of the wood sloping down to each side joining the slope away from the house. however, having set it out i'm thinking i may have cut the flags from the pin by the house to the middle of the wood and diagonally to each corner of the wood. but how do you make the decision on whether this needs doing?

is it case of suck it and see or is there a rule to follow regarding fall and distance?

[lutonlagerlout]

you definitely dont want to be cutting diagonals there mikey
diagonals are a sign that someone hasn't thought the job through or sett out correctly
i would keep it flat through that area or maybe even a slight fall towards the sleeper
than continue around the front section
your fall wants to be around1:60
you are 150 down from DPC but you could maybe leave 1 flag out as a planter /drain off point just to stop water pooling
cheers LLL

[Mikey_C]

yeah, I know what you mean, I didn't want to do it. but I didn't want the water sitting against the sleeper (to be honest, I didn't want the sleeper (the wife did)). I developed the idea after of one the many ejits that came round to quote for doing the work suggested putting a bump in that section to disperse the water.

despite having done the subase for the two diagonals, i took some rough measurements yesterday and i think i will have a 1in100 fall across the width of the sleeper, from the flags already laid towards the bottom of the photo.

i was also thinking if i didn't point the gap between flags and sleeper (which will always be expanding and contracting anyway) and put KDS in there the water should disperse down into the subase.

[dig dug dan]

surely the simplst thing to do is to have a small gravel strip, say 40mm, next to the sleeper for the water to drain into??
simple

[Tony McC]

You can get a bit of "twist" with each successive flag, increasing or decreasing the fall as required.

Diagonal cuts are usually an indicator that the wrong size of paving has been used. If flags need diagonal cuts, then smaller flags or even setts should have been used to achieve the twist. Even if it's just a single course of, say, 100x100mm Indiian sandstone setts as a break band, a hefty amount of twist can be generated.

[Mikey_C]

surely the simplst thing to do is to have a small gravel strip, say 40mm, next to the sleeper for the water to drain into??
simple

i did think about something like that, however what put me off and why i was thinking of the kds is that i have this gravel style water run off area and i'm fed up with pulling the weeds out.

ps the sub you see in the photo was made on site using your crusher.

[dig dug dan]

the sub you see in the photo was made on site using your crusher.

I thought it looked a decent product!

[Mikey_C]

You can get a bit of "twist" with each successive flag, increasing or decreasing the fall as required.

Diagonal cuts are usually an indicator that the wrong size of paving has been used. If flags need diagonal cuts, then smaller flags or even setts should have been used to achieve the twist. Even if it's just a single course of, say, 100x100mm Indiian sandstone setts as a break band, a hefty amount of twist can be generated.

I suppose that is the question, how much twist might I get, guess it will be suck it and see.

having started this patio I wasn't getting the time to work on it so I decided to get a few people round to quote for finishing it (this was before i had laid any flags). here are some of the comments i received.

"we're clever we don't try sort the joints as we go we lay all the flags and even the joints up with the saw"

the grit sand is over there for the bedding
"yeah, grit sand is the right thing to use, it creates a stronger mix, but i prefer building sand"

and the best till last one bloke, who wasn't available for three months (at the end of summer) "oh yeah indian sandstone we fit a lot of that, you should put pva on the underside, don't let anyone do it who doesn't put pva on" me "i've heard of sbr and cement to create a bridge bond but not pva" his reply "yes, pva is very, very similar product"

[lutonlagerlout]

pva is a similar product mikey and i used it successfully for years
LLL

[Mikey_C]

i got the impression he meant just pva, not a bridge bond. Also i thought pva wasn't waterproof and therefore useless outside in the ground.

[lutonlagerlout]

I have never used a bridge bond Mikey ,
I always knock the gear up strong 6:1 and like bricklaying mortar
only started using SBR when i heard about it here
I used PVA for 15 years with zero failures
but this was in my self taught era
a lot of lads use a basically dry mix for Indian stone IMHO that is where the lack of adhesion becomes a problem
cheers LLL

[mickg]

I used PVA from 1975 onwards and it was never an issue, plasterers used it prior to applying the first coat of render to a wall. tilers used it on bare plaster without any issues and now your a cowboy if you utter these words from your mouth

PVA is still used by a lot of the guys laying Indian stone and its applied as a watered down wash to the back side of the paving days before its laid, if SPR was used and it was splashed on the the face of the paving and left to dry it can't be removed

[cookiewales]

hi boyos pva has been used for years because its cheaper and am sure its fine under paving but have seen it used as a sealer on top this is the fail it goes like spilt milk sbr does not :Dam sure ronafix simone will put us right .ronafix is the bees knees but as dear as gold :p



Edited By cookiewales on 1357679062

[Mikey_C]

i'm happy to accept I might be being a bit harsh, but if the guy knows what sbr is and is still using pva?

Also what does he care, what I think? the guy was booked out till xmas/January at the end of August, whatever and however he is doing it, he is getting the business?

I suppose my line of think is the same as some of the guys on here, they are striving to be the best.

To clear it up in my head, what is the point in putting neat pva or sbr on the bottom of a flag. I've reread the bond bridge and slurry primers page on this site and talks about cement in the mix.