FIG. 3.12 TIMBER GRILLAGE FOUNDATION FOR WOODEN POST.
FIG. 3.13 TIMBER GRILLAGE FOUNDATION FOR MASONRY WALL.
The upper layer of the planks, placed (side by side) may be 7.5 to 10 cm thick, extending over the full width of the wall base, and running longitudinally along the wall. The lower layer of planks may be 5 to 7.5 cm thick, placed longitudinally along the wall. However, the lower layer of timber planks, an also the middle tier of timber beams, should extend to atleast 45 to 60 cm on either side of the wall footing base.