Accuracy of gradients....

[blanket]

When measuring the gradients of paving, how more or less (+/-mm) accurate a reading do you obtain using a roto laser level compared to using a metal straight edge and spirit level. In this case, the roto, spirit level and edge are in perfect order.

Thanks. :?

[dib]

If your spirit level and straight edge are perfect and you eysight is perfect then theoretically the spirit level will give you infinite accuracy. Hope that helps ;)

[Master Splinter]

Errr....it's paving. Measuring to the nearest centimeter is fine, if you are expecting a perfect 1 in 100 slope for a meter wide path, you'll be disappointed. Use whatever tool is easier to work with. A Stabila level should be good to measure to 0.5mm per meter, if you can read the vial well enough.