HandyDeck tiles can be laid on any sloping surface assuming that the slope is not so great that you can't actually walk on it.

In fact some slight slope is ideal as it allows water to drain freely away underneath the tiles.

If the surface slopes in multiple directions, then our tiles can normally cope with such changes in direction providing these changes are not dramatic.

In many cases, the roof may have some drainage holes at intervals over the surface.  Because the tiles have an open mesh base, you can generally lay the tiles directly over the top of these drainage holes.