The more the merrier
Having lots of power points is great - it is so much better and safer than using extension plug-in boards. Plugging too many things into a single power point can cause it to become overloaded - which might even lead to fires in the case of permanently plugged-in equipment.
Where power points are installed will differ from house to house, but in most cases the locations for your power points will be pretty much a foregone conclusion, provided that your house has been planned in a way that assumes certain areas will be used in certain ways. When in doubt, if you have the option to it's always favourable to install more power points than to have not enough.
Having lots of power points comes at a small cost though. Not only are you paying for more ‘bakelite’ (the charming, old fashioned term for switches and power points) you will also need to extend your switch box with more miniature circuit breakers (MCBs), and additional wiring. Either way, it's almost always cheaper to overcompensate when you're building than to try and add new power points to an existing home.
If an area is likely to accommodate many different appliances, a power track type solution (like the one pictured) can simplify things immeasurably and go a long way towards reducing clutter.
How many power points per circuit?
A circuit is a single cable supplying power points (also called GPOs - general power outlets) in your home. The circuit is connected to (and protected by) an MCB. There are basic rules about how much current will be used in a single circuit based on the number of GPOs it feeds.
To take a practical example: 20 GPOs, each rated at 10 amps (in practice this is 10 points each with two sockets) are assessed by the wiring rules as likely to need a maximum current draw of 10 amps. The assumption is that they will not all be used simultaneously - and won't necessarily be connected to appliances drawing 10 amps.
A typical modern home with three bedrooms will have in excess of 40 individual power points. By the wiring rules, that is assessed as a total current load of 15 amps (10 amps for the first 20 GPOs plus 5 amps for the next 20).
The sensible plan
Extending installations can be expensive, for a couple of reasons:
- The current carrying capacity of the wiring to your power points may not be sufficient if you are adding lots more power points, in which case extra wiring may need to be needed.
- You may need an extra circuit breaker to allow for the extra power points, for which you may not have room in your switchbox. This will add to the expense by requiring you to get a bigger circuit breaker.
Where possible, installing an adequate number of GPOs wherever they might be needed in the first instance is always preferable to trying to add them later on.