Can anyone tell me the best way of supporting a pergola's main beam to avoid sagging etc. The beam i have is a 5m span supported by 10cm x 10cm (BS4978) posts in an l shape in the front half of the pergola which is attached to the house. The gap between the 2 l shaped corners is 3.45m
The main beam is spliced together two pieces of BSen 14081-1 timber.
there are 8 beams going from front to back and willbe between 4 & 6 going from side to side.
The dimensions of the pergola are 5m (L) x 2.75 (d) x 2.4 (h). Ther are 8 supporting posts which are 10cm x 10cm.