Zero Energy Buildings and Insulated Ventilation Ducts
Partition of ventilation in final energy usage of zero energy buildings is appr. 9-14% depending on type of buildings. So, insulated ventilation ducts are one of the key element of designing zero energy buildings.
In buildings where ducts run through unconditioned spaces, air duct insulation is vital to preventing energy loss. Even in your living space, where the air ducts are exposed to constant temperatures, air duct insulation is beneficial in preventing problems such as condensation and growth of fungi and other microbes. Enlisted below are some of the benefits of air duct insulation in buildings.
1 – Saves Energy
In most buildings, there are unconditioned spaces such as the basement, attic and garage, where, depending on the weather, the temperature is much lower or higher than the conditioned living space. Air ducts transfer warm or cool air from the central conditioning unit to all the rooms in your home. When air ducts pass through unconditioned spaces, they lose most of the heat or coolness from the air they are carrying. The air that finally reaches you is not as warm or cool as required, because of the loss due to conduction. Air duct insulation can prevent this problem that can cause wastage of a whole lot of energy.
With insulated air ducts or foam ducts heat transfer reduces both inside or outside of air ducts. At the figure below heat transfer to cool air duct from outside is expressed. Heat gain should be as minumum as possible while transfering cool air to somewhere else with cool air ducts.
2 – Increases Comfort
In most homes, especially older ones, more than 20% of energy is wasted on loss of heat or coolness through conduction. Insulated air ducts are better able to retain the temperature of the air they are transporting, reducing energy wastage. The air that finally reaches you is closer to the temperature you desire, thereby making your living space much more comfortable.
3 – Beneficial to the Environment
By insulating your air ducts, you can maintain your desired level of comfort at home, without spending as much on energy. This is highly beneficial to the environment, and it greatly reduces your carbon footprint. It is worthwhile to remember that the process of generating energy costs much more than the actual price of the energy itself.
Insulated ducts reduce the carbon footprint and usage of natural resources with proper insulation thickness. At the figure below you can see yearly CO emissions, energy source and insulation thickness.
4 – Prevents Condensation on Ducts
Over time, air ducts are prone to condensation problems and dripping water. Air duct insulation provides a solid cover around the air ducts, thereby preventing this problem.
5 – Reduces Noise Transmitted Indoors
Air ducts can carry sound waves all around the house. Most of us are familiar with the popping sounds emanating from ducts as the weather changes. Air ducts can also carry sounds across rooms such as the noise of the furnace turning on in phases. With insulated air ducts, this problem is minimized and cross transmission of sound is kept to a minimum.
6 – Prevents Formation of Mold and Fungus
Condensation is a common problem with air ducts. Water leaks and moisture can lead to problems such as growth of fungi, mold, mildew and other microbes. This can also cause health problems in the members of your household. Air duct insulation is greatly beneficial in minimizing condensation around air ducts, thereby reducing the chances of mold, mildew or fungus growth in the periphery of the duct work.