We completted a large domestic job in Oaklands Welwyn where we had a 4ft ground level diference between gardens, so we had to construct a concrete gravel board retaining wall supported by 5in x 5in concrete slotted posts at 6ft centres 
to hold back the earth, then supplied and installed closeboard fencing with trellis on top supp
orted by 5in x 5in timber posts at 2.4 centres 21mts worth in length.
