Lighting Levels

There are two elements when considering Lighting levels for your new house.

  • Electrical Power (Watts)
  • Amount of Light (Lumens)


In the old days with incandescent bulbs it used to be simple, bulbs came in 40, 60 and 100watts and you were allowed up to 25 watts/square metre of floor space.

Now for your new build, in order to limit energy consumption, you are only allowed:

  • Indoors 5 watts /sqm (5W/sqm)
  • Outside 4 watts/sqm (4W/sqm)
  • Garages 3 watts/sqm

This doesn’t mean you have to have a gloomy house. 

Modern light fittings such as Compact Fluorescent Lamp (CFLs) and Light Emiting Diodes (LED) give much more light than Incandescent Bulbs.

The above power consumption figure are for the initial construction. (After handover you can add additional lights)


Probably the best way to think about lighting is to consider what task you are going to do.

Then look at how you will provide enough light in that area rather than the whole room.

Here are some suggested light levels for various tasks.

Under 10 lumens/sqm – Outside Security.

10-20 lumens/sqm – Conversation, Eating, Watching Television, General Circulation.

20-50 lumens/sqm – Cooking, Casual Reading, Bathrooms.

50- 100 lumens/sqm – Detailed Craft Work, Study.


A typical LED delivers around 80-100 lumens per watt so a single 10w LED will provide a high lighting level for a 10m2 room (1 watt/sqm)

For more posts see Electrical or Light Fittings


Time To Rethink Sensor Switches?

Sensor switches used to be thought of as a big power saving measure but these days I’m less sure.

30 years ago when light bulbs were typically 100watts and had short lives a sensor like this could save some serious power and cost of bulbs.

These days with LED bulbs that are are put out a reasonable light output using less than 10 watts I am no so sure.

When checking out a replacement sensor switch I found the switch consumes 6 watts of power (More than the bulb I was using)

A simple time switch only uses around 1 watt.

So the equation for power use could be

Sensor switch 24 hours x 6 + say 5 watts when light on  = 150 watts per day

Time switch 24 hours per day x 1 + 5 watts for light on for say 10 hours = 74 watts (half the power usage)


Which way would you go?



Smart Renovations to Save on Your Water and Electric Bill

Guest Post from Joel Sidaka

As a property owner, it is quite common to spend around $300-$400 on utility bills every month.

Sometimes, it can even go as high as $500!

This can be a hard pill to swallow.

Fortunately, you can reduce your utility bills by doing a few renovations and we have gathered some that are worth trying.

8 Ways to Save on Your Water and Electric Bill

1. Look at your Hot Water System

If you own rental properties, then you clearly have a real estate investment to take care of.

That means you have to be willing to do renovations that would help you reduce the utility bills to keep your tenants happy and content.

Heating hot water is one of the biggest power users in your home, and these days there are several alternatives.

A Solar Hot Water, or a Heat Pump, are both alternatives that can save between 60% and 90% of water heating costs.

2. Upgrade the Clothes Washer

With an energy-saving washer, it is possible to save water that could fill up three backyard swimming pools!

That means you’ll be able to save $135 per year, especially if you’re still using a washer that’s over 10 years old.

3. Weather-stripping Should Be Applied

Contrary to popular belief, weather-stripping is not that difficult to install, but the effects it could have are definitely life changing.

For instance, without weather-stripping, you can feel the cold wind coming through your doors, but once it has been installed, it will be able to keep the rain and air from coming in and out of the room.

It’s also an inexpensive project that wouldn’t take much of your time to install.

Even those without any home improvement skills are capable of putting these on.

4. Making Use Of A Smart Meters

More and more homes now have a smart meter, but are you taking full advantage of it?

Most electricity providers allow you to check your power use on an hourly basis using a phone app.
However, you ought to know that smart metering programs do vary, but the basic idea is the same.

We use that to ensure that we are minimising power usage when the tariffs are high and maximise it when power is either low cost, or free (If you have solar power).

5. Install Low Flow Fixtures

In Australia most properties now have low flow showerheads.

Don’t forget that other fittings can also be converted to low flow.

A small investment like this would allow you to save as much as 60% on your water bills.

6. Install Timers

Timers ensure that your water heater is turned off at night or when it is not in use.

If you do this, you will never forget to turn off the heater during peak hours.

7. Replace Your Existing Lights with LEDs

Compact Fluorescent Light (CFL) used to be one of the most effective ways to save money.

Things have now moved on with Light Emitting Diodes (LEDs) dropping on price.

These typically use half the power of CFLs (85% of incandescent bulbs), start faster than CFLs and last around 15,000 hours.

8. Look at Installing Solar Panels

With the popularity of solar  power on the roof Photo Voltaic (PV) Panels have never been cheaper.
With continually rising power prices the installation price can be recovered in a few years

Final Words

We all want to go green and be able to lower our utility bills.

By following these tips, you will be able to save a lot of money from utility costs.

You will also be able to ensure the satisfaction of any tenants you may have, at the same time.

Air Conditioners – Why The Star Rating Is More Important Than Price

I’m currently in the market for a Split System Reverse Cycle Air Conditioner.

I went round a couple of the big box electrical stores last weekend and saw several models in the 3.5kw range, with prices ranging from $650 to $1,000.

But is the higher star rating of the more expensive models worth the extra dollars?

Finding Out The Savings

Well I went to website to do a little investigation

I used their calculator and based my search on:

  • A 3.5kw Unit.
  • Heating for 5 months at an average of 10 hours per day.
  • Cooling for 7 hours a day for 2 months.
  • Power at $0.287 per kW hour.

The results were:

  • The best  6 Star unit would cost around $236/year to run.
  • The worst 2 Star unit would cost around $551/year to run.

That’s a huge difference of $315/year!

In other words buying the more expensive unit would be cheaper after less than 2 years!

When I decide to buy; I’m only going to be looking at the 6 Star units.

‘Green’ Beer Fridge

When you move into a new home most people like to get a new fridge.

Either the old fridge doesn’t fit, or just doesn’t look as smart as the rest of the kitchen.

So what happens to the old fridge?

If you are like me, it gets claimed as a beer fridge.

A lot of environmentalists say that running a beer/bar fridges is bad for the environment, as you are doubling the power use over a single fridge.

Not only that, but I estimate it is costing you around $0.30 a day (or $110 a year)

A Green Solution

Well the fridge is just a big insulated box, so it won’t warm up too fast.

And we are going to be getting solar panels.

Also I don’t have a beer before lunch time and rarely late in the evening.

So the new plan is to put a time switch on the fridge to run from 9,00 am until 7.00pm.

Time to cool the beer down after the solar panels start generating. . . . . . and the beer should stay cold until late in the evening.

Save Energy By Upgrading To An Eco-Friendly Property.

Guest post by Hubert Dwight

Many people are quick to complain about how high their energy bills are, but they fail to take any real action to minimise the expenses.

Inside the home, lighting, electrical appliances, hot water, heating and cooling dominate energy consumption within their property.

Improving consumption habits will make a difference, however leveraging energy ­efficient technology will allow people to make greater energy savings with very little effort.

Here are a few ways improvements can be made to the home.


A roof that is a lighter colour will reflect more light and heat, which keeps the home cooler.

According to Steve King, Senior lecturer of architecture at the University of New South Wales, this can potentially cut down air conditioning usage and costs by 1/3rd.

Glass on windows and doors.

Many homes tend to have the wrong kind of glazing for the climate in their area.

For example, homes in warm climates that have large double glazed windows may find that their property gains too much heat, thus forcing people to use air cooling systems more.

Alternatively, properties located in areas with a cooler climate tend may be losing considerable heat due to single glazing.

Upgrade to energy efficient lighting.

People can reduce their lighting energy consumption by fitting their property with LED light bulbs.

LED technology is great because it allows people to continue with their lifestyle, while drawing less energy to illuminate an area.

The bulbs are more expensive than incandescent, or fluorecent fittings, but they last much longer and provide better lighting.

Savewise, who are specialists in residential and commercial LED lights can help secure government subsidies for those people that are interested in upgrading their existing property to use energy efficient lighting.

Air conditioners

Air conditioners are an essential appliance that will make a property feel more comfortable.

It’s important to invest in an air conditioner that is energy efficient because it will consume less energy and incur a lower running cost.


People can provide additional insulation to their property to keep the heat from escaping.

Additionally, investing in heating through reverse cycle inverter air conditioning can be a cost efficient way to increase your room temperature without incurring a high energy consumption cost.


Refrigerators run 24h a day in the home and tend to consume a lot of energy.

To minimise the energy consumption costs, look out for appliances that carry the energy star logo and any energy guides that will advise you on the running costs of the fridge.

Another tip when purchasing energy ­efficient refrigerators is that a top mount refrigerator uses 15% less energy than a side ­by ­side refrigerator.


Investing in an eco-­efficient dishwasher will help to save water and electricity.

Look out for dishwashers that have a high energy star rating and also keep in mind that you should run the dishwasher overnight to take advantage of the ‘off­ peak energy tariffs’, or if you have solar panels when the sun is shining.

These are some simple ways to improve the eco-­friendliness of your property and it should reduce the overall energy consumption, which will save you money over the long ­run.


Review the appliances that are being used in your property and see where you can make an upgrade today!



Fridge Location

You may be out shopping for a new fridge to go in the new house


You may just want to check your existing fridge fits in the alcove in your new kitchen.

Whichever it is . . . . . Don’t forget to leave room around the fridge!


Both refrigerators and freezers work by extracting the heat from inside to a radiator coil on the rear of the unit.

If the air flowing past the coils is restricted the efficiency of the refrigerator will drop, and your power bills will go up.

I would recommend a space at least 25mm either side of the cabinet and 40-50mm behind and above the top of the unit.

Don’t then use these spaces to store trays, chopping boards, etc otherwise you are going to block that ventilation path.

I have heard of people installing an external vent behind a fridge mounted on an external wall. . . It seems like a good idea if you remember to shut the vent on hot days. (remember on a 30 + degree day the incoming air will be hotter than the air in the room)

Door Opening

To get drawers out of a Fridge or Freezer you normally have to open the door by much more than 90 degrees. (I have just checked mine and its about 135 degrees)

This means you may need more than the 25mm suggested above on the hinge side unless the front of the fridge projects forward of the alcove.

Built in Fridges

I’m not a big fan of built in fridges, but if you like them make sure that ventilation and door opening are fully considered before you buy.


Light Bulb Comparison

In a previous post on Lighting Levels I talked about using lumens to plan lighting. . . . . but which type of bulb should you use?

There are now 3 types of bulbs in common use

  • Halogen (A more efficient version of the old incandescent light bulbs)
  • Compact Fluorescent Lamp (CFL)
  • Light Emitting Diode (LED)

Light Output

Typical values of light output are:

  • Halogen – 15 Lumens/watt of power
  • CFL – 54 Lumens/watt of power
  • LED – 90 lumens/watt of power

Actual values will vary from manufacturer and also depending on the  colour temperature of the light.

From the above figure it can be seen that a LED provides a significant power saving, even compared with a CFL.

Initial Cost

For an output of around 450 lumens enough for something like a desk lamp you can expect to pay:

  • Halogen – $3
  • CFL – $6
  • LED – $20

Bulb Life

  • Halogen – 2,500 hours
  • CFL – 10,000 hours
  • LED – 50,000 hours

The long life of LEDs meant that though the initial cost of $20 seems expensive over the life of the bulb you would have needed 5 CFL bulbs ($30) or 20 Halogen bulbs ($60)

Other Issues

CFL lamps do contain a small amount of the toxic element mercury, and do take several seconds to Warm up to full brightness.

Both halogen and CFL lamps tend to have limited durability if subject to vibration or rough handling.

A dimmable LED is around 40% more expensive than a basic LED.


For more posts see Electrical or Light Fittings