10 December 2019
A sustainable house: good for the environment and for your wallet.
You want to reduce the environmental impact of your home. What do you need to look out for? And how do you finance a greener house? Here’s all you need to know.
A study by researchers Willy Baeyens and Hubert Rahier from the VUB has demonstrated that our country has huge potential when it comes to renewable energy. However, we also need to take action as citizens, as almost 20% of all C02emissions originate from our homes.
In this article we present a step-by-step plan explaining how you can make your home more sustainable. In this way you will be able to cut your home’s energy consumption and C02 emissions, as well as make significant savings on your energy costs.
What are the biggest energy guzzlers?
There are many ways to make your home more sustainable: extra insulation, energy-efficient windows, a heat pump, solar panels, etc. But where should you start?
The answer is a simple one: where most energy is lost. Do you lose most energy through your walls, roof or windows, or would you be better off replacing your old gas or central heating boiler?
An energy audit by an energy expert will highlight the weak spots in your home. You will then know immediately how much energy you can save where and how.
In many cases most heat is lost through the roof: 30% on average. Insulating your roof is therefore the best place to start. The minimum thickness is 3 to 4 cm, but you should ideally opt for a thicker insulation layer. After all, the thicker it is, the more you will save.
Your windows are also potential energy guzzlers, especially if you still have single glazing. However, even older double-glazed windows allow a significant amount of energy to escape.
It is therefore well worth considering high-efficiency glazing. The energy you save means this investment will pay for itself in around seven years.
After your roof and your windows, the best thing to look at next are your walls. By insulating your external walls, you can achieve energy savings of up to 20%!
You can do this in various ways:
- Cavity wall insulation is the most efficient option, but not all houses have cavity walls. External walls that are more than 24 cm thick probably have a cavity.
- Is cavity wall insulation not an option? In that case opt for external wall insulation. This will also give your home a new, modern look at the same time.
- Internal wall insulation is the least energy-efficient way to insulate walls. However, if you are planning to renovate your internal walls, this is certainly worth considering. You can also do this easily yourself, which will keep the cost down.
Floor insulation has the smallest impact on your energy losses but can nevertheless deliver substantial savings. In homes with a crawl space an uninsulated floor has an average temperature of 11°C. Floor insulation can quickly raise this to 20°C – you will really notice the difference in terms of comfort and in your wallet too, as a family with average annual consumption can save 200 euros a year thanks to floor insulation.
The most efficient technique is to insulate the underside of the floor via the crawl space. Is your crawl space less than 35 cm high? In that case opt for ground insulation, which involves installing insulating material on the floor of the crawl space.
Only once you have limited all your energy losses through your roof, walls and floor does it make sense to invest in a new heating system.
Here again you have various options:
- A condensing boiler recovers the heat present in the flue gases. As a result, it consumes up to 35% less than an old atmospheric boiler and 15% less than a high-efficiency boiler. Both gas-fired and oil-fired condensing boilers are available.
- Heat pumps extract energy from natural sources, such as air, water or the ground. You can use them to heat your home, but also for domestic hot water. Heat pumps are highly efficient and an excellent investment as a complete replacement for your central heating boiler.
Subsidies for solar panels have fallen sharply in recent years. Nevertheless, solar panels remain extremely cost effective.
The time needed to recoup an investment in solar panels is shortest in Brussels and longest in Flanders, but you should expect it to take 7-8 years on average. This difference is mainly due to the different grants and subsidies that may or may not be available in the various regions.
How can I finance my investment in an energy-efficient home?
Any investment in energy-efficient measures for your home will save you money in the future. However, many people are put off taking this step, as the initial investment is too high.
Nevertheless, there are various ways to finance installation costs:
- Use your own funds
- Apply for an energy loan from the Flemish government
- Apply for a loan from your bank
A range of grants are also available from regional and local authorities:
- Energy grants in Flanders via the grid operator
- Total renovation bonus (Flanders)
- Brussels energy grants
- Wallonia energy grants
Want to know more about renovating sustainably? Please read all our articles on sustainable living.
Also find out how loans from ING can help finance your sustainable renovation project.