Ventilation

Your ventilation is key to your indoor air quality (IAQ), your air’s moisture levels and the smells  that can build up in your home.  Below is a brief summary of some of the options that are available to you.  If you have any questions about using these in your home please let us know.

Supply Ventilation

  • Air quality 8/10
  • Cost 8/10
  • Efficiency 7/10

Supply ventilation is a fan supplying filtered outside air into specific rooms of a house (normally the bedrooms and the living room and/or family room).  The fan splits off into ducts that deliver the filtered low volume of air into these rooms.  When new air is introduced into these rooms other air must be displaced to the outside.  The displaced stagnant air is forced out through the leaks and cracks throughout the building.

Properly installed supply ventilation brings very good in air quality to the home and is inexpensive to run ranging from 35 watts and up.  The fan is set to run continuously at a very low air volume and cannot be heard or felt.

Exhaust ventilation

  • Air Quality 4/10
  • Cost 8/10
  • Efficiency 7/10

Exhaust ventilation is a fan exhausting air from one or multiple rooms in the house to the outside.  The stagnant air is exhausted out of the house and the replacement air comes in through either open windows or cracks and leaks throughout the building.  Just as with supply ventilation, the air from the fan is low volume and should be set to run continuously.

This type of ventilation is not very good for air quality compared to the other methods.  The air coming into the house is not filtered or controlled.  If windows are open it can bring in dust, pollen and other pollutants.  If the windows are closed then it can bring in air from sources such as your crawl space or attic.

There is energy lost with this type of ventilation because you are losing conditioned air via the exhaust fan and bringing in unconditioned air.

Balanced Ventilation (HRV / ERV)

  • Air Quality 10/10
  • Cost 6/10
  • Efficiency 10/10

Balanced ventilation is two part ventilation.  For every cubic foot of air exhausted from the house a cfm of filtered air is introduced to the house.  It is balanced so no uncontrolled air is introduced or exhausted from the house while completely ventilating the house.

Balanced ventilation normally refers to an HRV (heat recovery ventilation) or ERV (energy recovery ventilation).  They retain some of the conditioned air inside of the house before exhausting it outside.  In a cooling season the cool conditioned air passes through a heat exchanger, cooling it, and then the hot outside air passes through it.  The heat is then transferred from the outside air to the heat exchanger removing the heat from the air (cooling the air).  The air is then filtered and supplied to the house through the small ducts.  In the heating season it works in the opposite way.  The conditioned indoor air is exhausted out, heating the heat exchanger.  The cold outside air is drawn in passing through the heat, exchanger which heats up the air which is then filtered and delivered into the house.

HRV’s are normally recommended for deep energy retrofits and for homes in climate zones with a lager temperature difference from inside to outside.  They deliver amazing ventilation results and save up to 65% of the energy that is otherwise lost with normal ventilation.

Natural Ventilation

Natural ventilation is the air exchanging through your house naturally.

One type is opening windows.  Opening of windows or ports in the house can ventilate your house.  With a good wind pressure on one side of the house you can effectively ventilate.  Drawbacks are that you must depend on a pressure in order to bring the air through the house, it doesn’t remove all of the air, and the air coming in can be dusty, pollinated and/or polluted in other ways.  It is also unlikely that you will be opening up windows during when there is a large temperature difference from inside to outside which can leave you with stagnant, poor indoor air quality.

Your house can also breathe on its own.  Depending on how leaky your house is and what the pressures are (i.e.; wind pressure, stack pressure, etc.).  This type of ventilation can bring in very dirty air (from attics, crawl spaces and outside pollutants) and is inconsistent which can leave your house with stagnant, poor indoor air quality.

 

More Services Below