Sustainable Home Renovations – Homes for a better future 27

Sustainable Home Renovations Homes for a better future

I am a professional renovator specialising in sustainable home renovations and I am passionate about creating the change that is required to make Melbourne sustainable. Many people think that to be sustainable means going without – I’m here to dispel that myth.

Have you heard of the Tesla Model S? It is an all electric car that shows that a sustainable electric car can be better than a traditional car in every way. It is sexy, it is incredibly fast, hi-tec, comfortable, has range of 500km and is far cheaper to run than any other car!

Sustainable homes are just the same. They are more comfortable, healthy, beautiful and far cheaper to run.

I am creating a series of articles / blogs that will showcase some of the best sustainable homes in Melbourne. I want you to learn how to make sure your next build or renovation is as comfortable, beautiful, safe and sustainable as it can be. I want you to know that your existing building can be retrofitted to make it all of those things too.

To begin this journey I would like to start with an overview of what sustainability means and what makes a home sustainable.

So here we go!

Sustainability means living in such a way that it does not have a negative impact on the future generations. If you are a homeowner in Melbourne, you are aware of the wonderful diversity in climatic conditions that we experience, making typical Melbourne homes too hot in summer and too cold in winter. Our gardens go from wet and boggy to dry and brown!

In order to maintain a somewhat comfortable home and a beautiful garden most of us spend a small fortune on our utilities. But it doesn’t have to be this way!

I would like to share some of the things that I have learned from working with customers from all across Melbourne and Victoria to make their homes more comfortable, healthy, beautiful and sustainable.

Some improvements will include minimal costs and you can do them yourself, while others require a larger upfront investment and professional help. Let’s get started!

Design

Passive designs use the natural components like the sun and cooling breeze for heating  and cooling. This drastically reduces the energy consumption and when incorporated with the other features that we will discuss make it possible to have a home that requires no energy for heating or cooling. This is known as a passive house. If you are building or renovating, orientating windows to face north will make a huge difference to the comfort, sustainability and ambience of your home, filling it with natural light. This prevents the need for lights during the day and will help prevent the feeling of depression that overcomes many Melbourne residents during winter that is related to low natural light levels (Seasonal Affective Disorder or SAD). Furthermore careful design can incorporate insulated thermal mass in your renovation that helps to maintain a stable temperature in your home.

Unfortunately for many of us we are living in existing homes where the home is not orientated so that most of it’s windows are facing north. So what can be done?

Change room placements – move your living areas to the north side of the home and bathrooms, toilet and bedrooms to the south.

Add windows to the north side

If possible add north facing clerestory windows.

If you are renovating make sure that the new addition to your home is orientated correctly and zoned off from the rest of the home. Also include insulated thermal mass in your design to capture the heat from the sun. The thermal mass will heat with the sun and slowly release that heat through the night keeping the home temperature more stable. In summer, shading prevents your thermal mass from heating and instead it acts to keep your home cool.

If none of this is possible in your home then the following steps will ensure that the energy that you use for heating and cooling your home stays in your home for as long as possible.

Draught Proofing

No matter how much you insulate your roof, walls and floors, it won’t matter much if your front and back doors remain open. Think of being in bed, you have an incredibly warm dooner but it is suspended over you with a tunnel from your feet to your head where the cold air can pass through. While of course you won’t leave your doors open during the coldest nights in winter or the hottest days in summer, the gaps around the outside of your doors, windows, architraves and skirting boards, to name a few, certainly make it feel like you have. Cold and heat will infiltrate through those gaps significantly decreasing your comfort and increasing your environmental impact as your heat leaks from your home like a sieve. I suggest that draught proofing will arrest this unnecessary flow of energy out of your home and bring you a very large step towards a sustainable home.

Insulation

In my experience insulation is crucial to a sustainable home. Insulation should surround the entire building so that the internal temperature of the home can be as independant from the external temperature as possible! While installing insulation under the floor of a home another tradesperson asked me if it actually makes a difference in the home. I asked him whether it makes a difference if he wears pants or not. Of course it makes a difference, in fact many home-owners in very cold areas describe being able to feel the difference in temperature between the areas of floor that have been insulated and uninsulated as we are installing it!

Ratings for insulation in Australia are expressed in R values, the higher the R value the better. Because heat rises ceiling insulation should be the priority and in Melbourne the building code specifies an absolute minimum of R3.5 in the ceiling but I would recommend at least R4.5.

polyester insulation underneath the floor

Walls and floors should be R2.5 when it is possible. Insulation can be added to your existing home to bring the level of insulation up to these levels but make sure that the insulation that is used is installed correctly, effective for the life of your building and healthy.

Window Treatments

Double or Triple Glazing: While insulation ratings are expressed in the terms of a R value, windows ratings are expressed in U values and the lower the U value the better.

I mention this because once your home is draught proofed, windows are often the worst performing surface of your home per m2 of area. To explain this a typical u value of a single glazed aluminium window is U6.9. If this was expressed as an R value it would be R0.14. The minimum amount of insulation that you should have in your wall is R2.5! You can see how much more energy will be lost through this window. Close fitting heavy curtains with a pelmet, double glazing or triple glazing your windows will make them thermally insulated helping you to improve the energy efficiency of your windows. It will reduce the amount of heat going out of your home in winter and coming in during summer but not the heat coming in as a result of direct sunlight. This is a good thing as it allows the sun to heat your home in winter but it does raise another consideration: window shading.

Blinds:

Blinds do not only offer privacy but they can also provide additional thermal comfort in your home. Blinds with pelmets that are close fitting to the wall (ideally touching) and that reach the floor reduce the flow of air discussed up above even further and are particularly important with lower performing windows.  

Window shading:

While it is possible to purchase glass with coatings on it that reduce the heat from direct sun entering your home this is not desirable when you are living in Melbourne or Victoria. Our climate determines that we use far more energy heating our homes than cooling them and to lose the heat gain that we can achieve from the sun in winter would be counter productive. If you have ever climbed into your car that has had the sun coming through the dash window you will not be surprised to hear that the heat coming through a window from the sun can be as much as a bar heater going flat out!

So what’s the answer for summer? External, controllable window shading on the east and west side of your home and north facing window shading at the correct angle to prevent summer sun but not winter sun. Deciduous trees and vines can also work here but don’t offer the same level of control as they either have their leaves on or off and don’t allow you to control when the sun warms your home and when it doesn’t.

Heating Systems

Our traditional belief that Gas heating is more environmentally friendly no longer rings true. Reverse cycle split systems or hydronic heaters that utilise heat pump technology are now far better sources of heat for your home and I will tell you why.  They use 1 unit of energy to create 5 units of heat with minimal losses when delivering the heat to your home. Gas systems use 1 unit of energy to produce 0.9 units of heat (at best) but more typically 0.7 and then only manage to deliver 42% of that to your home as heat due to losses via the flue and ducts. On top of this the vents are always poorly installed with gaps around them that allow outside air to infiltrate your home. Ceiling ducted systems also encourage heat losses through the ducts that deliver the heat when the heater is not even on as the heat in your home rises, enters the ducts and is then lost into the ceiling through the thin insulation!

Cooling Systems

Fans and split systems are best. Fans are very effective in improving the comfort in your home as we are cooled by the passing air and they are very efficient to run. If the temperature in your home has however increased to such an extent that fans are not enough then split systems are the way to go. As discussed in heating split systems use heat pump technology to heat or cool the air by using 1 unit of energy to produce a certain number of units of heat or cold and choosing the right model will provide you with very effective and efficient cooling and heating.

Water heater

Here in Melbourne heat pumps are best. Water heat pumps take heat from the surrounding air to heat your water in the same way as split systems heat the air.

Cooking

Induction cooktops and electric ovens are best. They are more efficient, are better for your health due to not releasing pollutants related to the flame into the air and are faster at heating your food. This also allows your home to be gas free (see below).

No gas

Not using gas in your home means that there will be no gas connection fee (currently about $250 per year) and the potential to supply all your energy from renewable energy and making your homes energy supply as sustainable as it can be. You can also get  rooftop solar which means no more energy bills! If you would like to learn more about comparing the cost and environmental impact of using gas vs electricity click here

Water

Can you imagine how much water is wasted when we shower or take a bath? This not only wastes what is a very precious resource in Melbourne but also uses a lot of energy to heat the water. It doesn’t have to be this way.

The use of state of the art shower heads can make your shower feel every bit as luxurious but while using far less water (this also means less energy used heating the water and requiring the purchase of a smaller water heater).

There are also great options for reducing the water used by your toilet and sinks as well as re-using the water from your handbasin to fill the toilet cistern ready to flush your toilet with soapy water that keeps your toilet clean!

Once you have reduced the water used you can change the source of that water to utilise water captured from your rooftop. Water can be stored in tanks and then used to wash your clothes, fill your cistern,after it has been partially filled by washing your hands and to supply your hot water system.

Grey water for a lush garden

This tank water can then be used in the garden as grey water. Grey water is recycled water from your shower, washing machine and bathroom sinks can be redirected directly to a garden watering system that alternates where the water flows to, keeping your garden looking lush year round.

Even the black water from your toilet can be treated hygienically and converted into a valuable nutrient rich resource for your garden! I will provide an article on fantastic black water systems for tose of you that require one on your block or those of you that are sustainability enthusiasts!

Rooftop solar

The final step in a sustainable home renovation is to produce as much or more energy than your house requires from a sustainable energy source. For most households rooftop solar is the best solution. This can mean no more energy bills!