wrote:

Proper deck boards are slip resistant especially when traffic is 'across'
the board rather than along its length. Instead of grooves machined into
the surface, deck boards should have the surface machined away leaving a
series of ribs proud of the surface.

Maybe you could explain the difference?

Mark space ratio ;-)

How about alternate tread staircases? I built one once & my head still
hurts from working it out :-)

Yes, an article on those would be good too. You fancy saying something
about them?

same as cut string at a much steeper pitch really...

--
Cheers,

John.

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