The standard 6 inch and 12 inch smooth boards share the same 1.83m length and approximately 45 to 55mm depth, but the 12 inch board is 155mm taller. The existing post length and finished fence layout therefore still need checking.
The standard smooth 6 inch and 12 inch concrete gravel boards are designed around the same 1.83m fence-bay length, but changing between them alters the finished height of the fence.
Our 6 Inch Smooth Concrete Gravel Board is 1.83m long, 150mm high and approximately 45 to 55mm deep. The 12 Inch Smooth Concrete Gravel Board is also 1.83m long and approximately 45 to 55mm deep, but its height is 305mm.
The difference is therefore 155mm. If the same timber panel is retained above the new board, its top edge will sit 155mm higher than it did above the 6 inch board.
Both smooth boards are steel reinforced, vibration finished and intended for compatible slotted concrete-post fencing. The matching bay length does not automatically mean the existing posts are long enough for the taller arrangement, so check the available post height and the complete finished fence before replacing one size with the other.
Other profiles and heights can be compared under concrete gravel boards.