Dutch building regulations focus primarily on assessing buildings, as Jan Willem van de Groep observes in this issue of Zichtlijnen. We calculate energy performance, environmental impacts, daylighting, ventilation, overheating, and noise. Everything is assigned a standard, an indicator, or a threshold value. But is it really wise to assess buildings as if they function in a vacuum?
In the calculations we use to evaluate our buildings, we act as if a home were isolated from the street. As if an apartment on a paved square performed identically to a home next to a green park. As if a facade were influenced only by the sun and not by the tree standing in front of it. Yet we also know that the surroundings are at least as decisive as the building itself.
Take heat stress, for example. Concerns about overheating have rightly increased; homes are better insulated, summers are getting hotter, and tropical nights are no longer the exception. Preventing overheating has now become a serious challenge.
However, the reflex is predictable: we look for the solution within the building itself. Better glazing, active sunshades, more powerful systems, or even air conditioning. But in doing so, we’re mainly treating the symptoms. The temperature inside a home is determined not only by the building’s facade, but also by the temperature of the street, the amount of shade, the presence of greenery and water, nighttime cooling, and wind flow through the neighborhood. A home on a tree-lined street literally experiences a different climate than an identical home in a paved-over neighborhood. Yet our BBL standards hardly take this into account.
This leads to some curious situations. A developer who installs expensive exterior sunshades sees an immediate impact on the building’s performance. But a developer who preserves existing trees or strategically plants new ones receives hardly any recognition for it under the same system. Yet a well-placed tree can block a large portion of the sun’s rays from hitting the facade in the summer. Moreover, that same tree lowers the ambient temperature, retains rainwater, improves air quality, increases biodiversity, and enriches public spaces. A single intervention achieves multiple societal goals at once. Why don’t we value that systemic performance?
The same applies to water storage, grid congestion, health, and climate adaptation. These challenges cannot be solved at the individual property level; they arise from the interaction between buildings and their surroundings. It’s time to take the next step in our regulations. Not just standards for buildings, but also for neighborhoods. Why don’t we measure how much shade a street provides on a hot summer day? Why don’t we assess cool walking routes, a neighborhood’s nighttime cooling capacity, or the amount of tree canopy per home? Why isn’t a smart combination of building and neighborhood given higher priority than a mere accumulation of technical measures within the lot boundary?
Over the past few decades, we’ve learned to make buildings better and better. The next step may be even more important: not designing the perfect building, but creating an area where buildings naturally perform better. After all, no one lives in an EPC, an MPG, or a TOjuli calculation. People live on a street.
About Sightlines
Directions is my way of taking the conversation about renewal in construction a step further. Not by shouting louder, but by looking more sharply. I write about what is going on under the surface: the assumptions, the systems and the choices that determine what we build and why. My ambition is to give direction to a sector that is always in transition, but unintentionally still thinks in old patterns too often. What systems are still holding back a construction that wants to be faster, more affordable and more future-proof?
Jan Willem van de Groep
