Retrofitting: the offsite construction answer to the housing and energy crisis in Europe

January 5, 2023 by
Retrofitting: the offsite construction answer to the housing and energy crisis in Europe
Fjolla KAMBERI

Did you know about 25% of all energy we use in Europe goes to our buildings? Even over 50% in winter! When you know this, and you know that many of our current living facilities are not up to standard as far as energy waste goes, you also know there is a lot of potential to do better. 

“Tens of millions of houses in Europe need urgent renovation to mitigate significant loss of energy.” 

About 43 million houses in Europe need to be renovated and made energy neutral to reach our climate goals of 2050. At a rate of about 6000 renovations per day. A mindboggling number. The energy crisis of 2022 has only made that need more compelling. But it is possible, with deep energetic renovation through offsite construction. 


The fastest way to sustainable energetic renovation: retrofitting 

At BuildUp we are immensely proud to be a pioneer in retrofitting. A groundbreaking and innovative way of renovating. We renovate and refurbish existing houses with offsite produced facades and roofs. That’s right. We build wall and roof components to cover existing buildings. Completing net zero energy home makeovers at an incredible speed, following the Energiesprong approach: 

  • A house generates all the energy required for its heating, hot water and electrical need.  

  • You get superior indoor comfort as a great bonus. 

  • The cherry on top: we produce the Retrofit building elements with minimum carbon emission. 


A complete Retrofit project is composed of: 

  • Walls composed of internal airtight membrane, insulation, façade cladding, windows, and doors. 

  • Roofs composed of insulation and roofing 

  • Always included: engineering, transport, and digital building instruction 


7 benefits of retrofitting: a new, groundbreaking and innovative way of renovating 
  1. Saving on heating cost: retrofitting literally wraps a house in a new, energy neutral coat. Helping to cut energy costs and bill prices. 

  2. Durability: the new tech and sustainable materials increase the lifetime of the building with many years, while decreasing required replacement cycles and maintenance. 

  3. Improved comfort: the whole house gets retrofitted completely, addressing all air leaks an defective insulation. 

  4. Better for the planet: the house will become energy neutral, which reduces carbon footprint significantly 

  5. Less time on site: for every hour on site for offsite retrofitting, traditional retrofitting takes 27 hours. 

  6. Less labour cost: compared to traditional retrofitting, offsite needs less manpower on site. 

  7. Improved appearance: your home will look more appealing, increasing its value. 


Great strides have been taken in France and the Netherlands. But the needs of cities and housing companies in Belgium are just as dire. And quick, yet sustainable solutions exist. Together we can reach the goal of energetically renovating all houses by 2050. 


3 retrofitting projects by BuildUp 
Wattrelos: large scale energetic renovation of 153 occupied houses 

In 2022, we finished project Wattrelos. The first large-scale renovation project in Europe that is part of the Energiesprong building wave, in the pursuit of CO2-neutral housing. Through retrofitting, we made 153 occupied houses, that were built in 1950, energy efficient. We covered the existing houses with offsite produced facades and roofs, fitting 5 homes a day with a new climate jacket! With a promise of sustainability: 

  • 100% recyclable steel 

  • LEAN manufacturing minimizes waste in the factory 

  • 30-year performance guarantee proves efficient use of resources 

Now these houses are done losing energy left and right. We cut heat loss, power consumption and carbon emissions, giving those who live in them a breather on their energy budget. What a win! With a big shoutout to all the partners on this project: Vilogia, Septalia, Nortec Ingénierie, Redcat Architecture, Symoé, Rabot Dutilleul Construction and Pouchain SAS. 


Roubaix: 32 housing units get a climate neutral jacket 

At Residence Philippe Le Hardi in Roubaix, BuildUp gave 32 collective housing units an energy-efficient climate jacket with 600 m2 of roof and 1600 m2 of walls, all produced offsite. The apartments are now completely energy neutral, which means that they can generate all the energy they consume on their own for the next 25 years. 

The advantages for the renters are enormous: 

  • Higher thermal and acoustic comfort 

  • Lower energy bill 

  • A renovated kitchen and bathroom 

  • Lovely refurbished common areas 

The project is part of the Energiesprong renovation approach and was partly financed by the Interreg North West Europe (NWE) fund. We send out a big thanks to our partners Vilogia, Septalia, Altera, AIP, Entreprise Dujardin, and Puchain SAS. 


Lille: 2 schools to be made fully energy neutral 

The next Energiesprong project for BuildUp will be in Lille (Rijsel): energetic retrofitting of 2 school groups. In total we’ll transform 6 school buildings to energy consumption level E=0, following the Energiesprong guidelines. We’ll cover no less than 3800 m2 of roof and 5000 m2 of walls with energy-efficient roofing and facade panels. In addition, the used materials are circular and of biological origin, to keep the energy cost of production low. 

Because the buildings are in use, offsite construction is the ideal construction technique for this project. Thanks to the quick installation, the insulated roof and facade panels can be installed in July and August. This way the students are not disturbed by the building process.