In part one of this post, we looked at how precast concrete can help keep houses and buildings cool thanks to thermal mass, as well as insulated structural walls. In part two, we look at precast concrete geothermal systems, ensuring quality despite high temperatures, and reducing the “heat island” effect.
Precast concrete pipes can be buried under houses and larger buildings and used as part of a precast concrete geothermal heat pump system. If you’re not familiar with geothermal heat pumps, they use the relatively constant underground temperatures as a thermal exchanger to efficiently heat and cool a space above ground. This reduces a building’s carbon footprint and its total operating costs.
In addition, precast concrete is made in a controlled environment where the heat of summer will not affect the quality of the end product. When temperatures rise, cast-in-place concrete can be affected in a number of ways. The most significant is the rapid evaporation of water in the mix, which causes the concrete to cure too fast and crack. This, in turn, impacts durability and strength. In a precast plant, concrete cures the same way, day in and day out, despite the elements.
Another benefit of precast concrete during sweltering summer temperatures is probably the one that links closest to the lyrics of that song by “The Lovin’ Spoonful” that was cited in the first part of this post. Concrete, thanks to is light coloring, has a much higher solar reflectance index (SRI) than darker materials and thus reduces what is known as a “heat island” effect. If you’’e ever entered a dark car that’s been sitting in the sun, you know firsthand how much heat dark materials absorb. And while precast concrete structures can’t stop a heat wave, they can cut down on pollution by using special additives that give the surface photocatalytic properties.
When it comes to reducing the effects of extreme heat, there’s no better material than precast concrete.