Building Sciene Series #4

2024-01-29

Source: Build Science 101 - Episode 4

Energy Efficiency and Environmental Responsibility

Efficiency is a byproduct of comfort; The one rule for comfort: Heat moves from hot to cold.

There are 3 forms of energy transfer.

Conduction

• passing through materials

Convection

• the movement of particles, for example, air or water

Radiation

• Energy that comes from a source and travels through space, e.g. sun rays

Solar gains

For Radiation it's essential to consider the house orientation and glancing Area.

Generally want larger Glazing Area towards the sun in colder climates (Glazing Area = Window Area / Solid Wall Area)

The varying Sun Elevations over the year allow different configurations of solar gain.

• Overhangs provide shades in summer, with summer at a higher angle.
• But on winter days, the sun is lower and allows it to penetrate deeper into the house.

Additional helpers allow further control. Shades outside allow a block of radiation before they enter the house. If the shades are inside, they only block the light but not the Energy.

Environmental Responsibility

• A House built to last a hundred years reduces the environmental footprint. Durability is key! Material choices affect the impact of hardwood floor vs vinyl.
• Hardwood can be resanded and last a long time; vinyl gets thrown out after X years
• Consider the embedded Energy in the products you use.