The major items in Electrical & ELV are the second/third fixes like Busbars, Cable ladder, tray & trunking. The flexibility of these makes them the most easiest (except for Busbar) of the service to reroute or offset where required.
Busbars
Since Busbars are the heaviest of MEP services, with respect to the routing, this heaviness factor should be considered.
While busbars are usually designed from Susbstation to the Main panel (MSB/MDB) or from MDB to the SMDBs in each floor (thru Electrical shaft) in a high rise building, the route should be designed in a way to avoid MEP congestion.
But if unavoidable, make sure that the busbar is taken away from plumbing lines or CHWP.
Apart from Busbar, note the following for other Electrical & ELV services:
Easy Manouvering
So an Electrical & ELV service can be played around wrt MEP co-ordination without much intellect. But the only area where the problem comes is the cable sizes. Since the cables are installed at a later stage, always remember the size of cables which the cable tray carries. For heavy cables (above 150mm square), it is always adviced to minimize offsets (both horizontally and vertically). Atleast sufficient space for the offsets should be given considering the effort for sharp bending. For eg. a 45 degree bend or offset instead of 90 degree.
Lowest Service
Always remember, the cable laying will be done sometime after cable tray installation. In this timegap, other MEP installation would have been completed. Hence, its always advisable to route the cable tray at the lowest point or just above the false ceiling (in RCP area). This helps cable laying easy unaffecting other services.
The only check to be done is that no drainage/water lines are running parallely above these trays/ladder.
The telecom authorities install their cables on the final stages. So the ELV cable tray is recommended to be the lowest or just above the (wherever) false ceiling.
Light fittings
The number of light fittings will be more than any other final fix in MEP. Hence, the height of light fittings which will take space above false ceiling needs to be considered. Generally this being 10cm for normal lights, the MEP services are run atleast 15cm above the RCP so that the lights can be placed without any hindrances. A thorough check on the height of lights for customised lighting projects will benefit the MEP coordination in a better way.
Concealed Point wiring
To help MEP co-ordination, the point wiring containment (conduits) can be made concealed (using PVC pipes) instead of open GI conduit. This has to be done during slab/core wall casting. This will save a lot of time and labour during the MEP installation. This will also avoid the amount of trunking used which will also a cost saving.
These above points if considered, will ease the electrical part in MEP co-ordination.
Next topic: Effect of Supports on MEP Co-ordination.