Air Management Technology
The Problem: We’re Starving For Fresh, Clean Air
The air inside a building is the worst air on earth, and we spend over 90% of our time inside of buildings.
According to a 1994 study by the California Environmental Protection Agency Air Resources Board, the average human breathes about 20,000 liters – that’s almost 6,000 gallons of air – every day. Now see what’s in that air: You’re Breathing Too Much Bad Air
Remember all those tiny holes we mentioned on the Landing page that we said aren’t exactly letting clean air into the building after all? It turns out that since air flows both ways, it’s a double-edged sword cutting away at not only our health, but slicing through our wallets at the same time. As uninvited dirty-air flows in through tiny holes in one side, rich conditioned-air flows out through tiny holes in another.
Together, those holes added up come to roughly the size of a beach ball. That dust all over the furnishings is transported in on tiny air currents as it rushes in gathering toxins, fungus, bacteria, insects and particulates nestled in the wall cavities and dark spaces on its way. Filtering out through other tiny holes as it leaves, it’s blowing the expensive warm or cooled air out.
It’s called air infiltration. In properly air-sealed buildings the Air Management System no longer has the job of processing and filtering all that additional air, and THAT changes EVERYTHING.
Knowing that fiberglass actually accumulates and then releases the finest particulates and fibers into the air, it seems absurd to think that we rely on these kinds of filters in our clean the air we breathe. If you have fiberglass filters in your air handling system now, we strongly suggest you exchange them for non-fiberglass electrostatic filters.
Usually these filters are made from fiberglass similar to the insulation in our walls that so casually releases stored filth into tiny air currents wafting in through the nearly undetectable holes in a building’s exterior walls.
Currently, most air filters actually exacerbate the problem by broadcasting the tiniest, most breathable particulates around the building.
In A Perfect World we would never have to think about being hot or cold. Our goal is to achieve this ideal in your building, in such a way as to actually make you smile when the utility bills arrive.
We love the summer sun, the snow and the rain. But we just wish it wouldn’t get too hot, too cold or too wet. The feel of a tepid zephyr on the skin can be a comforting, rich experience. When it’s too hot any breeze is nice, cold or warm (cooler is better though, eh?) – and when it’s too cold we want to feel warmth on our skin.
Quick Physics Review
Heat flows from hot to cold by three mechanisms: conduction, convection, and radiation.
- Conduction: the molecule-to-molecule transfer of kinetic energy (one molecule becomes energized and, in turn, energizes adjacent molecules).
- A cast-iron skillet handle heats up because of conduction through the metal. Wall studs allow more energy to pass through than the insulated cavity between them.
- Convection: the transfer of heat by physically moving the molecules from one place to another.
- Hot air rises, heated water thermosiphons. Forced-air systems work by moving air around. Air barriers prevent heat loss from air infiltration.
- Radiation: the transfer of heat through space via electromagnetic waves (radiant energy).
- You can feel the heat of sunshine through a window, and a campfire can warm you even when there’s a breeze – because radiation is not affected by air.
The Convection Connection
We all know hot air rises; convection right? And of course, heat moves to cold and vice-versa – but more slowly – in thermal conduction. We account for radiation in the positioning of windows, and certainly include such things as U-values, glass surface areas etc. in our calculations – but solar radiation is the low rung on the priority ladder.
As for radiant heat, we’ll get to that in another section.
Our buildings are air-sealed, so getting adequate fresh air in and circulating energy-efficiently is essential.
Mechanical systems – particularly HVAC systems – deal with the air handling that is now our main focus. Why? Because air circulation, fresh air introduction and stale air (CO2) exhaustion overpowers all other considerations in air-sealed buildings.
How do we air-seal new buildings? See here: Building For Performance.
We’re concentrating on controlling, channeling and restricting air-movement in an air-sealed environment.
To successfully accomplish this in the most efficient way, we have consider such things as internal building pressures and air leakage, exactly where the air comes from and goes to, and how it moves around inside the building.
In the olden days (gosh, at least 5 years ago or more) this is what we discovered about air-loss: it’s where most of the money we spend on energy goes. It’s not through those sacred insulated “high-R-value” walls – it’s through air “infiltration.” So by air-sealing we stop most of the energy loss.
The rest of our energy losses go into heating and cooling air where we don’t need it… largely because of the Stack Effect.
Countering the Stack Effect
When a building is heated, the warm air inside rises, creating a high-pressure zone near the top floors or attic of a building. Opposingly, a low-pressure zone forms in the basement and bottom floors. The area in between these two zones then becomes a neutral pressure zone.
This air-pressure configuration is called the Stack Effect, and it exists in every type of building on the planet. The high-pressure air above the neutral zone tries to escape from the building and move towards the lower pressure outside the building. Because the air in the basement and lower floors has lower pressure, the air from outside tries to enter the building through any available openings.
Air-sealing a building is a giant step towards energy efficiency, but it’s not the end-all of the equation. Did you know that sleeping in an airtight room without adequate ventilation has been called a symptom of “sick building syndrome?”
Together with the solar powered Environmental Automation System, properly installed Passivecore™ elements in the wall cavities will passively counter these effects. At the same time they help maintain more consistent building temperatures in a healthier environment while significantly aiding to reduce energy costs.
Go here for more details on: How To Passively Counter the Stack Effect
We use a passive air circulation system to help counter the stack effect naturally by capitalizing on how building pressures are continuously attempting to equalize. This not only allows fresh air to circulate more freely around the building, it helps to extract the stale air, and keep temperatures more consistent.
Passive air circulation systems may get fresh air in and moving around, but they have some limitations with regard to temperature control, so we have to rely on mechanical systems for solving some heating and cooling issues. For the basics of HVAC systems, the whys and hows – go here: HVAC and ERV Systems
To find out how we handle the integration of mechanical and passive air handling systems, and other things like humidity control, fresh air processing, purification systems, energy recovery ventilation and stale air/toxic gasses removal, see here: The High Velocity Solution