1. Mark all pipe entries on the pit and/or riser walls or use the preformed standard pipe entry guides/plastic inserts on the pit walls as a guide (Figure 1 & 2).
2. If multiple pipe entry is required, refer to the relevant regulatory authority for minimum cable separation spacings. ACO recommends a minimum of 50mm between penetrations to avoid local cracking.
3. Using a diamond tip holesaw of required size, remove the pit wall to fit the pipe (Figure 3). ACO offers a range of holesaws to facilitate this operation, click here.
4. A small diameter masonry grinder may be used to enlarge the opening for pipes entering the pit at an angle.
5. For multiple pipe entries, ACO recommends a concrete haunch around the all the pipes to preserve pit rigidity. Minimum of 100mm concrete encasing is recommended around the pipes and 200mm measured out from the pit wall. Concrete to be fully compacted and of grade 25MPa*. (Figure 4)
6. Install the pit and pipe. Cut the pipe flush with the inside wall of the pit so that the clear working area of the pit is not impeded.
7. Seal connection with a proprietary cementitious sealing compound to prevent ingress of moisture into the pit during service.
For pit installation details, click here.
* Adverse ground conditions may require an increase in these dimensions and/or the addition of reinforcement. If in doubt, engineering advice should be sought.