Passive Systems in the Green Design Process

This is perhaps the more interesting side of the green building process because this is where form and function meet. Lets start off with a simple illustration to give you a clear understanding of passive design. We will use a sailboat as an example; to keep things simple, this sailboat is made up of a hull, sails, and a small auxiliary engine. When designing this sailboat, the engineer wants to maximize the efficiency of the hull and sails (the passive components) - by reducing drag and increasing effectiveness of the sails. As these passive aspects of the boat are improved, the need for the auxiliary engine (the mechanical system) is reduced. 

This translates to your building as well, the more ambient resources (sun, water, and wind) that can be taken advantage of due to passive design means less of a need to use the cities utilities, or expensive and invasive mechanical systems.

Now that we have an understanding of the purpose of passive systems, lets look at some of the most popular ones in more detail. 

 

Daytime Lighting

There are 3 main reasons that natural daylighting should be integrated into the design of your building, lets review them below:

  • The sun is constant, it appears every day and unlike the lights in your home, you don't have to pay for it. The sun is a free source of energy, its advantageous to you and the environment to use as much of it as you can.
  • Sunlight is more appealing to us than artificial light, there is nothing like it. Natural sunlight has a warmer more comforting tone that reduces stress and actually makes people feel more positive. It also supplies us with important Vitamin D, a vitamin necessary for your immune system to function properly. According to some studies it also makes us more productive during the day, and helps us sleep better at night. You can read more about this here. Architectural Lighting 
  • There are also clever ways to actually absorb the suns heat energy into your building - this is mentioned below.

 

Passive Heating

Is achieved mainly through product selecting products that have a high thermal mass, or resistance to temperature changes. Certain materials such as stone, concrete, and tile can absorb the suns heat energy quite effectively. This can be used to your advantage when designing your project, for example; when a tile floor is exposed to sunlight during the day it absorbs that heat energy. As the sun sets the sunlight disappears but the tile floor stays warm and slowly radiates that heat back into your building. This effectively gives you free heating during the evening and night. 

What if you don't want this heating during the summer months though? Your architect and us as your contractor can work hand in hand to have your building designed accordingly - because the suns path changes from season to season, we can make sure that your design lets sun on these thermal mass areas more during the winter months and less during the summer ones.

This image was taken in December at our Evergreen project. Firstly note how deep the sunlight penetrates into the room, this was by design; during the summer months the floor in this room sees almost no direct sunlight at all. You can see the dark stone floors that absorb the daytime sun (yellow arrows). The floors would then radiate heat throughout the night (orange arrows,) majorly reducing winter heating costs. If you find a certain space too warm, you can add an area rug (as seen in the picture.)

 

Cooling & Natural Ventilation

In the previous entry that talked about mechanical systems, we covered Radiant Heat, Heat Recovery Ventilation, Forced Air Heating, and Air Conditioning. What we didn't talk about is how to offset those systems using the design of the building itself. 

Your site typically will have a predictable air current that usually peaks during temperature surges (in the morning and evening.) By placing windows on opposite sides of the building, parallel to the air current, you can channel the earths natural air current through your building to cool your space. To take this design idea even further, you can apply a solution typically called “stack ventilation” that will work even when there is no breeze.

The images below from our Belmont project illustrate the way that stack ventilation works -  warm air rises, so we give it a place to escape usually at the highest place in the building. That warm air leaving the building through the elevated window stack pulls cool air in from the windows on the stories below. This creates a naturally ventilating space that supplies itself with cool and fresh air. 

When planning a ventilation stack, you need an open space that connects the different stories in your building together. Usually a staircase is the best location to implement stack ventilation as all floors are connected to it. We can help you decide on the most practical yet convenient location and products to implement stack ventilation.

 

 

 

At Meister Construction Ltd. we put forward our best effort to work with our clients and their architect in order to implement the best design, and to build you the best quality product that will suit your needs. If any of these concepts or solutions are something that you would like more information on, please feel free to contact us at info@meisterconstruction.ca for further discussion and inquiries.