Vondelweg en Roerdompstraat
Haarlem
60 homes
2025
Remanufactured MV boxes with moisture
sensors
Project Vondelweg and Roerdompstraat
If this story sounds familiar to you, you’re right. Earlier in 2025, Interduct’s company RenovAir dismantled the mechanical ventilation boxes at four apartment buildings in Beverwijk for BAM Wonen and Pré Wonen. The parties agreed to refurbish the dismantled ventilation boxes and reuse them as remanufactured units on this next project in Haarlem.
The 60 homes in Haarlem received appliances that have been given a technical and cosmetic makeover from Interduct’s existing stock. “This is not the same as second hand,” says project leader John Gaikhorst. “They look and feel like new boxes. In fact, they may even be better than the originals because they are completely up to date."
Good as new with a moisture sensor
In this case, up to date means that the Itho Daalderop MV boxes, which are comparable to the CVE-S type, have a moisture sensor as an expansion on the circuit board. The moisture sensors work with the CO2 sensors in the bedrooms and living rooms to form a demand controlled ventilation system. The boxes have a DC motor, giving them a lifespan which is at least equal to that of new boxes.
In renovation projects, it is sometimes difficult to find the right spot for the ventilation system. For this project, RenovAir mounted the box above a dropped ceiling in the toilet. From there, the exhaust duct goes through the kitchen to the bathroom. “This was the most logical solution," says John. "Otherwise, we would have to go through an existing shaft and take fireproofing measures. Taking into account fire safety, installation, maintenance and costs, this was not the ideal solution.” From the box, the dirty air exits through the back facade. Fresh air enters through newly installed window vents.
The power of collaboration
RenovAir’s fitters see little difference: the ‘touch and feel’, the installation and calibration are no different than with a new appliance. Only the pre-installation phase differs: old ventilation boxes are first collected and refurbished, and then delivered and installed. Rogér Keijsers, Business Development Director at Interduct, is responsible for ensuring that this process runs smoothly. Sister companies have also contributed to this project: Robé delivers the ductwork and fittings, and VentTrade the hooded grilles. This enables us to ensure a sustainable, healthy, and comfortable indoor climate for residents — and help create a circular world.
Project Vondelweg and Roerdompstraat in photos
