Laying slabs with a fall

[bigboss34]

Wondering if anyone could give me some advice

I'm laying paving slabs which is 22ft length by 6ft width and was wondering I if need to leave a fall?

the slabs are 450mm square so a 1.60 fall would make around a 6mm fall in each slab?

I'm going to use a line but would a digital spiral level work for more accuracy?

also what would be the worst if I didn't leave a fall? would it just be water building up on the slabs?

Cheers

[lutonlagerlout]

is this a wind up?
all paving needs a fall BIG BOSS

the only slight exemptions are landings on disabled ramps but even they will have a 1:100 fall
for slabs at 450 mm you want about a 1:75 fall

so you need about 90mm if falling the 6.6m way
cheers LLL

[bigboss34]

Thanks for the reply

If I do the fall width way which is 6ft how much would the fall have to be then?

[lemoncurd1702]

Thanks for the reply

If I do the fall width way which is 6ft how much would the fall have to be then?

25mm should do it depending on the slabs and how good your laying is. What is it falling to though.

[bigboss34]

it will be falling onto grass

so that would make each slab fall of just over 6mm?

Would a digital spirit level get a more accurate fall on each slab with using a line aswell?

isn't a fall noticeable?

[lemoncurd1702]

Falling to grass, great! 6mm about right but would concentrate on fall over 6ft rather than individual slab. Sounds like you got a new toy, haven't used one myself.
The fall is only noticeable if you overfill your wine glass.

[bigboss34]

Thanks for your help

To do a fall over 6ft do you use a line and drop the line by each set of slabs?

[lutonlagerlout]

set up 2 datums 1 at one end of the 6ft and one the other
then ping your line between these
anything over 1:50 isnt really noticeable for pedestrian stuff
LLL

[bigboss34]

cheers for your help, seems a bit tricky, I'll try it however if I can't work it out I'll try a digital level as I doubt there will be much difference between it?

[seanandruby]

Big boss you don't need any fancy toys for levelling slabs, a string line and a hand level and 3 metre straight edge are adequate over 6 freet. Don't over think it, once you see the string lines in place it will be a light bulb moment :;):