Page 300 - B6118-AEW-XX-XX-PP-A-0001_(P19)_Contractors Manual

CONSTRUCT

C2 External Works

C2.1 Ducts and Draw Pits

New ducts installed must be provided by 100mm
dia UPVC flexiduct laid min cover -300mm,
more typically -600mm below local finish level;
final depths to be designed by contractor to suit
site ground conditions. Straight ducts must be
retained in place with concrete haunches at
min 1200mm centres. Any bends within the duct
to be fully set in concrete and must be formed
in propriety 100mm dia swept bends (not tight
90 degrees).

Proprietary draw pits should be installed as
required where numerous ducts congregate
for pulling into the building or further around the
site. Duct chambers to be 600x600mm footprint
with proprietary flush metal cover plates.

All ducts to be laid with draw wires ready for
pulling of electrical cables.

All installed ducts should be sealed at each
end on completion using wire mesh (max 10mm
gaps) set in expanding foam, min 100 deep.

C2.1 Ducts and Draw Pits 1.0 08 October 2014