What does Building Performance mean to you?

Energy efficiency

Factor4 is the architect of the energy efficiency project in your organisation.

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CO2 reduction

Factor4 guides you to a CO2 neutral operation. We mix energy efficiency, renewable energy and CO2 offsetting.

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Return on Investment

Factor4 supports owners and managers of real estate portfolios both at strategic and operational level.

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User well-being

Factor4 assesses building performance based on the user’s well-being. We focus on the main comfort parameters: temperature, acoustics, air quality and light.

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Peace of mind

Factor4 can unburden you of all energy-related tasks. We are your external energy manager.

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Factor4 makes sure that organisations comply with regulations and standards related to energy efficiency and building performance.

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Every day, we see buildings that do not perform. They consume too much energy, maintenance costs are too high and people living and working in them are unhappy, unproductive or even sick.
Business as usual is not good enough.
We believe buildings can perform better: they can be more efficient and more comfortable.
Performance contracting is a very powerful tool in upgrading and managing buildings. We want to use this advantage to the maximum extend.

Johan Coolen


We don’t sell equipment or materials. We develop improvement projects and focus on the result. We are prepared to take our responsibility and share the investment risk.
Our customers are SME’s, large companies, communities, schools, apartment buildings, energy cooperatives and public authorities.
We provide solutions from start to finish, covering all relevant techniques.
We participate in several research projects related to innovation in the field of performance contracting and energy efficiency.

Sven Wuyts


‘Factor four’ refers to a fourfold increase in ‘resource productivity’ by simultaneously doubling wealth and halving resource consumption.
The idea was introduced in 1998, in a book written by L. Hunter Lovins and Amory Lovins and Ernst von Weizsäcker.
The concept ‘Factor 10’ also exists: in the long run, resource use needs to be slashed tenfold when we aim for a true sustainability…

Office in Belgium
Lange Winkelhaakstraat 26
B-2060 Antwerp
T +32 3 225 23 12
Find out here how to reach us and where to park.

Office in the Netherlands
Cronenburg 152
1081 GN Amsterdam
T +31 20 50 41 570


VAT 0884 068 589
IBAN: BE34 7795 9242 3490
RPR: Mechelen

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