Switching a whole home to LED: which bulbs to replace first

Switching every light in the home to LED saves money and time when it is planned. The steps, from making a list to checking compatibility and disposing of old lamps.

A home usually has more light points than people expect. Ceiling lights, chandelier arms, wall lights, table lamps, bathroom, balcony, garden, plus fridge and cooker hood bulbs: count them all and thirty or forty is quite normal. Replacing them in one go, at random, means extra cost and a risk of unsuitable bulbs. A planned switch lets you see the benefit of each step.

Step 1: map the lighting in your home

Go room by room and record for each light point:

• the room and fitting (ceiling light, wall light, table lamp, spot);
• the number of bulbs, cap type (E27, E14, GU10, G5.3, tube) and shape;
• the lamp type (incandescent, halogen, fluorescent, already LED) and wattage;
• whether the fitting is enclosed or open;
• whether it is controlled by a dimmer, sensor or timer;
• an estimate of its daily burning time.

Making this list for the first time often brings surprises: forgotten halogen spots, an old tube in the basement that burns every day, a chandelier with bulbs of different colours.

Step 2: set priorities with numbers

For each point, work out wattage × daily hours. The biggest figures go to the top of the list. The order often looks like this:

• main kitchen and living room lights, which run longest;
• ceilings full of halogen spots, because of the number of lamps;
• outdoor and entrance lights, which burn through the night;
• hallways and stairs;
• bedrooms and bathroom;
• storerooms, basements and rarely used decorative lights.

One exception: whenever a bulb fails, replace it with LED straight away regardless of its place in the list. You are buying a new bulb anyway, so the extra cost is minimal.

Step 3: check compatibility

Once the plan is ready on paper, check the technical conditions for each group. The points that come up most in homes:

• Enclosed shades. In a sealed fitting with no airflow, an LED bulb runs hotter. Look for a note on the packaging about use in enclosed fittings.
• Dimmer circuits. Only dimmable LED bulbs belong here, and an old dimmer may not cope well with an LED load.
• Motion sensors and illuminated switches. The indicator light in a switch or a two-wire sensor can make an LED glow faintly when off.
• 12 V spots with transformers. A transformer sized for halogen lamps can behave erratically when the load drops to a few LED watts.
• Appliances. Fridge, oven and cooker hood bulbs work in special conditions; follow the appliance manufacturer’s recommendations for these.

Leave any change that involves the electrical circuit to a qualified electrician.

Step 4: plan a consistent look

A gradual switch carries one risk: the home fills up with bulbs bought at different times in different colours and brightness levels. Avoid this by deciding in advance:

• one colour temperature for living spaces, for example warm white;
• neutral white where needed for work zones such as a kitchen worktop or a dressing area;
• only one model within a single fitting, chandelier or group of spots.

If you are unsure about colour temperature, try it in one room and live with it for a few days. Once you have decided, keep the same choice for the other rooms.

Step 5: retire old bulbs properly

Working old bulbs do not have to be thrown out immediately; they can serve in a rarely used spot or as spares. But dispose of failed ones properly: fluorescent tubes and compact spiral lamps contain mercury and must not go in ordinary rubbish. Wrap incandescent and halogen bulbs without breaking the glass so nobody gets cut.

Track the result

Note the meter reading or your recent bills when you start. Compare after a few months and you will see the difference. Seasons, air conditioning and other appliances also affect the bill, so comparing with the same months of the previous year is more accurate.

While planning, the savings calculator on this site helps show the yearly kWh difference for each group. With your list complete, each line can be matched to a Zəfər İşığı model: the catalogue covers E27 and E14 bulbs, GU10 and G5.3 spots, filament lamps and high-output types.