Studio Negri News

Energy Efficiency Tips for Eco-friendly households

Many existing houses could be more energy efficient. Sustainable architecture in Ireland is not just about adding better insulation, using alternative fuel sources, or creating smarter exposure to natural light will all add to efficiency. These structural changes can be expensive. But there are options. The following tips will ensure that energy savings are possible without spending more money.


1. Lower your thermostat by one degree C and save 240 kg (529 lb) of CO2 per year. If you feel cold, put on another layer. A cooler temperature is healthier and makes you more active.

2. Turn the heat right down at night. Use warm beds with hot-water bottles, not electric blankets.

3. Turn off your heating when you are not at home. Don’t heat an empty house.

4. Keep furniture and curtains away from radiators to prevent them from blocking heat.

5. Keep curtains closed at night and ensure that the curtains don’t hang over the radiators. Lined or interlined curtains are more insulating.

6. Place foil panels behind radiators to reflect heat into the room.

7. Fit radiators with thermostatic controls so that you can control heat levels in each room.

8. Fit hot water cylinders or tanks with thermostats and make sure the temperature is no higher than 60°C (140°F).

9. If you have gas central heating and your boiler is coming to the end of its life, install a new condensing boiler, which is highly efficient.

10. Take short showers instead of baths to save the energy that goes into the heating water.

11. Sign up to a green energy provider that invests in renewable schemes.

12. Have your boiler regularly serviced so that it operates as efficiently as possible. If your home is heated with a forced air system, change the filters regularly.

13. When buying heaters, make sure that they are the right size for the rooms they are to heat, and that they have thermostatic controls.

14. Remember that electric heaters other than storage heaters consume electricity at the most expensive charge rate.

15. Use a space or portable heater instead of the central heater, if only one room needs heating.

16. Heat bedroom areas with less than 18 degrees.

17. Twenty degrees C is an ideal room temperature. Turning down thermostats by 1 degrees can reduce annual space heating energy consumption by 10% with an equivalent reduction in greenhouse gas emissions.

18. Open fires are wasteful of energy with more than 70% of the energy going up the chimney.

19. Heating hot water accounts for 64% of energy consumption in the home: you should be thrifty in its use.



1. If replacing the hot water cylinder, a cylinder with factory applied insulation should be considered. Such insulation is more effective at retaining heat than a lagging jacket, is less easily damaged and cannot be pulled out of place.

2. A lagging jacket on your hot water cylinder will keep water hotter for longer and pay for itself in 2-3 months

3. Wall insulation can be increased in a number of ways. The pay-back period is dependent on a number of factors including type, thickness, and quality of existing insulation. The most popular types of insulation systems are, (i) insulated dry lining, (ii) blown mineral or cellulose fiber or polystyrene beads into the cavity, or (iii) rigid external insulation with render or brick finish. Specialist advice should be sought in all cases.

4. Insulate your attic well and save up to 20% on your home heating bill. If your attic insulation is currently less than 200 mm, then you should add further layers. There are a variety of suitable materials including mineral wool, rock wool, sheep’s wool, polystyrene, cellulose fiber and multi-layered foil.

5. Insulate under floors if possible.

6. Draught-proof windows and doors and cover letterboxes and keyholes.

7. Choose double glazed units when replacing windows. Much of the heat loss from a house occurs through the windows particularly if they are single glazed. Significant energy savings can be achieved if double glazing has Argon fill and low-emissivity glass. Fit low-E glass in areas where you have extensive glazing, such as in a conservatory

Energy Efficient Electronics


1. If you are replacing an old appliance, opt for the most energy efficient, which will typically consume a third less energy. In Britain, the most efficient appliances are graded A**. In the United States, look for Energy Guide or Energy Star labels. An ‘A’ rated appliance will use about 55% of the electricity of a similarly sized appliance with a ‘D’ rating. Always look for the energy label and purchase ‘A’ rated appliances where possible, they can save their replacement cost over their lifetime and benefit the environment.

2. Defrost your fridge and clean dust off the coils at the rear on a regular basis so that it runs more efficiently. Site it away from ovens or boilers so that it doesn’t have to work too hard. Don’t leave the door open for the same reason. Check the seals to make sure that the doors to the fridge and freezer compartments close properly. Check that the door seals on the refrigerator and freezer are tight fitting – the seals hold a 5 euro note in place when the door is closed.

3. Don’t put hot or warm food straight into the fridge — let it cool first.

4. If you have a chest freezer, put it in a cool environment, such as a basement or garage, where it won’t have to work so hard.

5. Freezers work best when they are stocked to near capacity. Refrigerators, on the other hand, are most efficient when they are no more than three-quarters full.

6. Make sure that you run full loads in the washing machine and dishwasher, and wash at lower temperatures or on eco settings – 30°C.

7. Some dishwashers and washing machines have a ‘hot fill’ feature that allows them to be connected directly to your home’s hot water supply. This means that the hot water can be heated without using electricity, for example by a solar thermal panel. 90% of the energy consumption of washing machines goes on heating the water. Stop the dishwasher before the drying cycle and open the door to let the dishes air dry and always use the economy button where possible.

8. Wash clothes whenever possible in cold or cool water.

9. Only boil as much water in a kettle as you need. If you are only making one cup of tea, only boil a cup of water. A new eco’ kettle features a central reservoir and a measuring button that releases the required amount of water for boiling into a separate chamber.

10. When you are cooking on a hob or stove, use the right size ring for the size of the pan. If you put a small pan on a large ring, 40 percent of energy you are consuming will be wasted heating the air. Unless the recipe states otherwise, cover pans so that the contents heat more quickly.

11. Turn off your oven five minutes before the recommended cooking time. It will maintain sufficient heat to cook the food. Energy-efficient ways of cooking include using pressure cookers, steamers, and microwaves. Toasters use less energy than grills. Convection ovens use less energy than standard ones.

12. Try to avoid using the dryer. In warm or dry weather, dry clothes outside on a line. Alternatively, you can use ceiling-mounted wooden clothes rack on pulleys or a similar kind of airer. If you must have a dryer, choose a model that has a fast spin cycle, which dries clothes more quickly, and remember to clean the lint filter regularly to ensure that it works most efficiently. Dry heavy articles separately from light articles and turn the dryer off as soon as the clothes are dry – don’t over dry the clothes!

13. Relax your standards a little. Sweep or mop instead of frequent vacuuming. Reuse towels rather than washing them straight away.

14. Give up the hairdryer and towel your hair dry instead.

15. Put lids on pots and turn down the heat when the water starts to boil. The lids not only keep heat in the pot but also reduce condensation in the kitchen.

16. Lots of energy saving cooking devices are underused: like slow casseroles, insulated deep fat fryers, microwave ovens, and pressure cookers. They can save both energy and time – with better results!

17. In a microwave oven, arrange unevenly shaped items with the thickest portion to the outside. Stir or turn the food over to speed up cooking time. Remember a microwave is more efficient than a cooker for reheating food.

18. The oven is expensive to use – try to use it as sparingly and efficiently as possible. Where possible use it for more than just one item and remember you can cook at a higher temperature at the top of the oven, and simultaneously at a lower temperature at the bottom.

19. Do not open the oven door to check cooking – every time you do so you lose 20% of the accumulated heat.



1. Before you even consider electric lighting make sure you make maximum use of all available natural sunlight. Daylight provides a healthier indoor climate, can provide higher standards of visual comfort and makes for more enjoyable interiors. And that is apart from the energy savings and environmental benefits.

2. Get into the habit of switching off lights when you leave a room

3. Dimmers allow you to only use what level of lighting you require at any time and so control the amount of energy you use. Dimmers cannot always be used with CFLs so check the product packaging or manufacturers details before use.

4. Movement sensors, time delay switches etc. are all available to improve lighting efficiency, but good manual operation of lighting in the household is always vitally important.

5. Rooms should be furnished to allow daylight in, and activities for which daylight or sunlight are essential should be positioned near windows.

6. Furniture and other obstacles should not obstruct daylight penetration of the room. Net curtains hamper daylight penetration of a room.

7. Dirt can reduce lamp efficiency by 20-25%.

8. Paint the surfaces of rooms, including ceilings, with colours of high reflectance to maximise the daylighting opportunities (and also the effectiveness of artificial light). Light colours can reflect up to 80% of incident light while deep/dark colours might reflect less than 10% of incident light.

9. Dirt on vertical windows can reduce performance by 10% and even more if the dirt is allowed to build up on roof-lights.

10. Use task lighting (e.g. desk or reading lamps) when required for locally high levels of light. A desk located away from a window may need additional artificial lighting while a desk near the window may often have more than sufficient daylight.

11. Make the most of natural light to avoid unnecessary use of artificial lighting

12. If you keep the lights burning when you are away from home as a security precaution, put them on a timer so they aren’t on all the time

13. Use solar-powered lights in the garden

14. Compact Fluorescent Lamps (CFLs) use 80% less electricity and last up to 10 times longer than ordinary light-bulbs.

15. In some situations the use of strip fluorescent lighting may be appropriate – if this is the case then be sure to use the 26mm tubes which are 10 -15% more efficient than their 38mm counterparts.


1. Switch it off. Don’t leave TVs, DVDs, set-top boxes, stereos, amplifiers, printers and other electronic equipment on standby. A DVD player on standby is still using 85 percent of the energy dial it uses when you are actually watching it.

2. Turn off your computer when you are not using it. Computers in sleeping mode use almost as much energy as they do when they are being used.

3. Laptops are more energy-efficient than desktop computers.

4. Unplug chargers, for example mobile phone chargers, after you have finished charging. A charger that is warm to the touch is still drawing energy, even if you have taken away the charged device.

5. Resist the temptation to upgrade to energy-hungry equipment, such as plasma TVs.

6. Only switch on the television when there is something you want to watch. Don’t leave it on in the background all the time.



1. Smart meters give you the information you need about your patterns of energy consumption. These don’t cost much and some electricity companies are considering providing them free to their customers in the near future. Ireland is considering offering these to all its electrical customers in the near future.

2. Standby savers or kill switches, which enable you to switch off all those devices that are normally left on standby at the press of a button, are another good idea. One type of standby saver looks like a standard extension cable. You plug all the equipment you would normally leave on standby into the sockets and then when you use the remote control to switch off the TV, power is cut to the other devices, too.

3. If your home is being fully rewired, or if you are building from scratch, kill switching can also be achieved by doubling up the power circuits. One circuit supplies power to appliances that need to stay on all the time, such as fridges, as well as appliances that we are accustomed to switching off, such as lights and irons. The other circuit supplies power to appliances that are often left on standby. These can then be centrally switched off after use or at night.




Conran, Thomas, Eco House Book, 2009, Conran Octopus Ltd, London

Studio Negri Dublin Architect Award Winner  Studio Negri RIAI Certified Architect Based in Dublin Studio Negri RIAI Certified Architect Based in Dublin
IGBC Certified Architect in Dublin Studio Negri member of the Architectural Association of Ireland Passive Architectural Designs in Dublin

STUDIO NEGRI © 2018, Dublin Architects
71 Greentrees Road, Terenure, Dublin 12.
Tel: +353 86 821 2674 |