Hızlı Git
When you walk down the street, the ground beneath your feet is the quietest counterpart of the light drifting down from the sky. Sometimes it reminds you how a black T-shirt heats up under the summer sun, sometimes it recalls the calm coolness of a white shirt. In cities, the phenomenon we call the “urban heat island” is built on exactly these simple differences: surfaces either absorb light or send it back. What I have observed most often in the field is this: the color and texture of the ground is not merely an aesthetic choice; it can have a decisive influence on pedestrian comfort, energy consumption, children’s play experience, and even how the late-afternoon breeze is felt.
Why “Light-Colored”?
Let me start with an everyday analogy: in summer, if you park a black car in the shade and a white car in the sun, your willingness to place your hand on the hood changes. Pavements work the same way. Light-colored surfaces have higher reflectance (often referred to as “albedo”); by reflecting a larger portion of incoming solar radiation, they can limit excessive surface heating. This can help reduce the mean radiant temperature felt at pedestrian level and, when combined with shade, can visibly improve the walking experience.
Of course, the effect of light color is not only “heating up less.” Lower surface temperatures can reduce the thermal load a pavement releases back into its surroundings on hot days; this can help cooling start earlier in the evening, especially in densely built-up areas. Although the numbers may vary in the literature, in the field you can feel the difference in thermal behavior between dark asphalt and light-toned surfaces under the sun even by placing your hand on them. Thinking of that sensation accumulated at the scale of the city is enough to convey the magnitude of the picture.
The Aggregate Question: Limestone, Granite, or Basalt?
Aggregate is the name given to granular, inorganic materials with different mineral structures—such as sand, gravel, and crushed stone—used with cement and water in concrete, mortar, and similar mixes. Aggregates make up roughly 75% of the volume of cementitious systems. In cement-based construction, aggregates are relatively inexpensive materials. With this feature, they reduce overall mix costs. Aggregates also make important contributions to the technical performance of cementitious systems. (1)
Aggregate is the soul of a pavement. It determines the tone, the texture, and the relationship the surface builds with light.
- Limestone and light-colored granite derivatives generally provide higher reflectance. In chip-seal (surface dressing) details, using light-colored aggregate can quickly transform the visual and thermal character of ordinary black asphalt.
- Basalt and dark granite can be more durable and harder; however, they are expected to absorb more heat under the sun. While dark stone may support ice melt at a micro scale in winter, it can increase the heat load in summer. This is why a climate-informed balance is needed.
When selecting aggregate, not only color but also particle size, porosity, hardness, skid resistance, and freeze–thaw durability should be evaluated together. A light-toned stone that creates a glassy shine on the surface can pose a glare risk at high solar angles. For this reason, it can be wise not to keep the surface too smooth and to disperse reflections through micro-roughness.
Three concepts appear frequently in the technical literature: albedo (reflectance), emissivity (thermal emittance), and SRI—Solar Reflectance Index (an index that evaluates albedo and emissivity together and allows practical comparison). Albedo indicates how much solar radiation a surface reflects; emissivity indicates how effectively, once heated, the surface can re-radiate that heat. SRI translates these two parameters into a “comparison language,” weighing different materials on the same scale. The SRI value in a catalog should not be the sole decision-maker; but between two candidate materials, it can offer a functional shortcut to the question “which one tends to stay cooler under summer heat?”
The Nuances of Light Color in Cold Climates Like Erzurum
There is one truth years of walking the field in Erzurum teaches you: winter rewrites design. Although light-colored pavements look very attractive for summer, two effects should be considered in winter. The first is glare: on a snow-covered day, when the sun appears, bright surfaces can challenge visual comfort and dazzle the eyes. The second is snow-and-ice dynamics: darker surfaces can absorb more heat and slightly accelerate ice melt, while lighter surfaces may remain more “neutral.” This does not mean “light color is bad”; it simply reminds us that we must think together with the winter season. For example, when light color + a well-textured surface + the right salting/cleaning routine are combined, both summer coolness and winter safety can be achieved.
In children’s play areas, I tend to use the following approach: the play core and the circulation belt can be handled with different color and texture strategies. A combination of fall-protective surfaces (e.g., colored EPDM or light-toned mineral infills) and light-to-mid-tone, high-friction surfaces in surrounding circulation zones can keep the ground cooler in summer and safer in winter. When it merges with tree shade, the effect becomes more pronounced.
“Color Alone” Is Not Enough: A Three-Way Alliance with Shade, Wind, and Water
Against the urban heat island, color is a powerful but, on its own, a limited tool. Light-colored pavements need to be supported by active shading (trees, pergolas), airflow (wind corridors), and water cycles (permeable surfaces, rain gardens, evaporative cooling). When a light surface “marries” shade, pedestrian comfort can increase in a way you immediately feel. A plaza with very high albedo but no shade can still feel “bright yet hot” in midsummer; whereas even a small amount of semi-permeable shade can change the sensation dramatically.
Pavement Systems: Thin-Coat Paint or an Integrated Solution?
Solutions marketed as “cooling paint/coating” and the “cool pavements” approach—where colored aggregate is integrally bonded within the system—are different. Thin-film coatings may deliver high albedo at the beginning; however, performance can decline over time due to soiling, abrasion, and UV. When the aggregate itself is light-colored, the tone comes from the body of the material, so the service life can remain more consistent. Even small steps in the maintenance plan—such as annual cleaning or periodic pressure washing—can help keep performance alive.
We do not have to imagine light color as “pure white.” The human eye is usually less disturbed by matte, natural stone tones. That is why the off-white, beige, and light gray family is often more balanced in terms of both thermal performance and visual comfort. Shaping surface texture with micro-roughness that scatters the sun’s angle; avoiding glossy, glassy reflections is a good principle. In children’s play areas, colored patterns (play cues, ground graphics) can be solved with calm, low-glare contrast palettes rather than excessive brightness.
Light-colored pavements are sometimes chosen with an expectation of a “smooth look,” but safety comes before aesthetics. Slip resistance in rain and ice (micro/macro roughness) and compatibility with wheeled mobility such as strollers and wheelchairs must be tested. Aggregate size and binder ratio influence both friction and vibration comfort. For that reason, in children’s spaces I often suggest different particle sizes and different binder ratios between the “play surface” and “parent circulation.” A small distinction can create a large comfort difference.
In fighting the urban heat island, looking at the price tag alone can be misleading. It should be approached through a life-cycle lens: initial construction cost + maintenance + renewal period. A permanent tone that comes from light-colored aggregate can be more stable over time than the first brightness achieved by paint. Adding a periodic light cleaning program for surface soiling and oil stains helps spread performance over the years. Writing this plan from the start reduces surprises.
Choosing light-colored aggregate and pavements may look like a small detail at first glance in the fight against the urban heat island, yet it can build a bridge between daytime coolness and the evening breath of a city. I like to design that bridge by placing color next to shade, texture next to safety, and surface choices next to a discipline of maintenance. Perhaps the point is not to make the ground “snow white,” but to create a matte calmness—at peace with the summer sun, measured with winter snow, gentle for children’s knees yet firm underfoot. Remembering that the coolness we seek in the heart of cities is often right beneath our feet is sometimes enough.
