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    Energy-efficient refurbishment – The savvy way to save on energy costs now

Components for energy-efficient refurbishment

Energy-efficient refurbishment involves upgrading buildings to minimise the energy used.

There are many possibilities when it comes to energy-efficient refurbishments. Before you get started, it is best to get an overview of the different options available. 

There are two important ground rules:

  1. Reduce energy consumption by adding or improving insulation
  2. Replace oil or gas heaters with a sustainable alternative

On the one hand, energy-efficient refurbishment has the advantage of reducing ongoing energy costs and CO₂ emissions. On the other hand, the refurbishment contributes to a more comfortable indoor environment and reduces the need for heating, as less cold air can enter the building from the outside.

Insulation – reducing energy consumption

"Good insulation is the basis for an energy-efficient building. But what does it mean?"

Most of the energy used goes into heating. Air-tight walls can therefore reduce energy consumption significantly.

This has several advantages:

  • In winter, although less heating is required, the property is better insulated and feels warmer.
  • In summer, the property is protected from overheating – air conditioning is often no longer necessary.
  • Energy consumption is reduced, leading to lower running costs.

Does the entire building need to be insulated, or is it more effective to only insulate individual areas? The possible insulation surfaces can be roughly divided into two groups, each of which has different advantages:

Top-floor ceiling

Warm air rises to the top. This is where most heat is lost. The top-floor ceiling is therefore a good place to start when retrofitting a property for energy efficiency.

Exterior walls

Insulating exterior walls not only reduces the energy used, but also improves the indoor environment. There are a number of ways to achieve this, including external thermal insulation composite systems or a ventilated façade using materials such as mineral wool or sheep’s wool.

Basement ceiling

Up to ten per cent of the energy used for heating can be lost through an uninsulated ceiling in the basement. Insulation of the basement ceiling generally retains more heat indoors and creates a pleasantly warm floor on the ground floor.


To further optimise energy savings, energy-efficient windows are required. This allows for seamless insulation, reducing thermal bridging in the building envelope. As well as improving thermal insulation, it also improves acoustic insulation, which is a pleasant side effect.

Heating – sustainable sources of energy

"Phasing out oil and gas" is the guiding principle for new or replacement heating systems. And for good reason: the running costs for oil and gas have been increasing over the past few years. The effects of climate change are visible everywhere and require a rapid change of course towards renewable energy sources.

"As part of a complete refurbishment package, the source of energy – the heating system – should also be checked."

Many questions come up when you change your heating system:

  • What are the alternatives?
  • Is it technically possible to make the change for my property?
  • Is it a worthwhile investment?

An energy consultant can answer these and all other questions. Below you will find a guide to getting started:

Solar energy

Photovoltaic systems convert sunlight directly into electricity using solar cells in solar panels. This means that the electricity can be used directly, such as in household appliances. Or it can be stored in batteries. The battery is needed to provide solar power even when there is little or no sunlight.

  • The installation of a photovoltaic system on the roof is usually straightforward and can be done by a professional. They are often used in combination with another type of heating system. In this way, energy costs can be reduced in the long term and the environment protected.
  • By contrast, solar thermal systems use the energy of the sun collected by solar panels to generate heat. This heat can then be used to heat water and support the heating function.

Wood energy

Wood is a sustainable and renewable resource if it is locally sourced and only as much is used as can grow back at the same time. Burning wood releases energy. This in turn can be used to heat water and for heating. In addition, burning wood, with the right fuels and correct operation, does not pollute the air. Pellets, logs or wood chips are most commonly used for this purpose. 

Ambient heat

Heat pumps are currently one of the most popular heating systems for new buildings, especially detached and semi-detached houses. There are different types of heat pumps that draw their energy from the environment.

However, the basic function is always the same:

  • The heat pump uses an environmental heat source such as the ground, groundwater or air. 
  • This heat is pumped to a higher temperature using electrical energy and then released into the heating system. 
  • There are also different options regarding the pump action.
  • Many heat pumps can also be used for cooling in summer, similar to an air conditioning system.

An expert can help you find out which one is right for your property.

District heating

District heating usually involves a power plant producing heat as an industrial by-product or specifically for the power plant. District heating in the form of circulating hot water can be connected directly to the property using a piped system. A transfer station is located at the property, which acts as a heat exchanger and transfers the heat energy to the house. In addition, there is often a hot water tank that stores the thermal energy and heats the water for the property.

Mortgage and home finance options

We can offer you different solutions depending on your objectives and requirements. And as different as the mortgage models may be, there is one thing that they all have in common: they are based on interest rates that are either variable or fixed for a certain period of time. Combining different models for flexible solutions, we use both to your advantage. We will be happy to advise you.