Hello. I have a large slate patio (crazy paving style) which is laid on sand. The gaps between the paving are large (I would guess around 3cm wide). The grout has failed and is crumbling out. Can anyone suggest the best method to repair / replace this? Resin seems to be not an option because of the area and size of the gaps (Patio area is roughly 80 sq m). A dry concrete / sand mix would seem to be the logical choice to me but I understand they are also prone to fail. Many thanks for any tips. Steven
