Electrical Datum
One datum per point. No site guessing.
v1.0 · 6 Oct 2026
Measured FFL → CL
Every height is measured from finished floor level (FFL) to the centre line (CL) of the accessory — not the underside of the box, not the top of the plate. Set FFL from the finished floor build-up, not the slab.
The floor box is the one exception: it sits flush with FFL, and its position is dimensioned on the plan.
The nine numbers
Every point on the schedule except the floor box takes one of these nine heights, in millimetres.
- 350General
- 600Low appliance / outdoor
- 700Bedside
- 950TV
- 1100Desk / island
- 1150Kitchen worktop
- 1200Service / fridge / vanity
- 1400Controls / isolators
- 2200Hood / AC / high-level equipment
The schedule by use
Heights in millimetres, FFL → CL.
| Point | Datum height (mm) | Placement rule |
|---|---|---|
| General 13A socket | 350 | Dry-area universal socket |
| Bedside socket / USB | 700 | Above typical bedside cabinet |
| TV console socket | 350 | Low equipment zone |
| Wall-TV power + data | 950 | Concealed behind TV |
| Desk / study socket | 1100 | Above typical 750 mm desk |
| Router / network equipment power | 1100 | Prefer dedicated structured-media location |
| Point | Datum height (mm) | Placement rule |
|---|---|---|
| Kitchen countertop socket | 1150 | Typical 900 mm worktop |
| Kitchen island socket | 1100 | Side/end panel, not worktop surface |
| Refrigerator dedicated socket | 1200 | Adjacent accessible service zone, not trapped behind fridge |
| Dishwasher socket | 600 | In adjacent cabinet/service bay, never directly behind dishwasher |
| Under-counter oven connection / socket | 600 | Adjacent cabinet/service bay |
| Built-in oven isolator | 1400 | Accessible outside appliance cavity |
| Built-in microwave socket | 1400 | Adjacent service cabinet |
| Coffee-machine / appliance tower socket | 1400 | Accessible within adjacent appliance/service zone |
| Cooker / induction hob isolator | 1400 | Dedicated circuit; not directly above hob |
| Cooker hood socket | 2200 | Concealed/accessibly located above or within hood cabinet |
| Point | Datum height (mm) | Placement rule |
|---|---|---|
| Washing-machine socket | 1200 | Beside machine, away from hoses |
| Dryer socket | 1200 | Dedicated accessible point |
| Point | Datum height (mm) | Placement rule |
|---|---|---|
| Mirror / mirror-cabinet power | 1200 | Coordinate basin/mirror geometry |
| Bathroom shaver socket | 1200 | Only where wet-zone requirements permit |
| Instant water-heater isolator | 1400 | Outside inappropriate wet zone |
| Storage water-heater isolator | 1400 | Accessible outside wet zone |
| Point | Datum height (mm) | Placement rule |
|---|---|---|
| Air-conditioner isolator | 2200 | Near equipment, accessible for servicing |
| 15A dedicated AC/equipment outlet | 2200 | Where equipment/system specifically requires 15A |
| Water-pump isolator | 1200 | Accessible, dry/serviceable location |
| Point | Datum height (mm) | Placement rule |
|---|---|---|
| Outdoor general socket | 600 | Weatherproof and above normal splash zone |
| Balcony socket | 600 | Weatherproof |
| Autogate power / isolator | 1200 | Protected service location |
| CCTV / security equipment power | 2200 | High-level service point where appropriate |
| Point | Datum height (mm) | Placement rule |
|---|---|---|
| Floor box | 0 · flush with FFL | Flush with finished floor; location dimensioned in plan |
| Point | Datum height (mm) | Placement rule |
|---|---|---|
| Light switch | 1400 | ELS control datum |
| General appliance isolator | 1400 | ELS common control datum |
How to use it
- An ELS design standard, not a statutory height. These are the heights ELS draws and coordinates to. No regulation sets them.
- The appliance manual wins. Check dishwasher, oven, fridge, AC, water heater and cooker connection positions at design freeze.
- Wet zones win. Bathroom points go only where the wet-zone requirements permit.
- Plan position is drawn, height is this sheet. Mark the wall and offset on the M&E plan; the height comes from the schedule.
- Wiring is done by a registered electrical contractor.
Not on this sheet?
A point this schedule does not list (for example an under-sink water purifier or an EV charger) is set per project and drawn on the M&E plan until ELS adds a datum for it.
Download the sheet
The PDF and CSV are issued in English only.