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Can you be too green?

Having a green home often means low energy which equates to a tight home. How tight-,some say 100% tight and condition all the air brought into a home and recover any heat exhausted from a home. That means the mechanical system needs to be maintained and in perfect running order.
I have done many surveys for energy loss and I always find places for improvement, but I am troubled with how tight to make a home. There is something said for health. A new home has many odors that may not be pleasing for sometimes months and windows need to be opened.

One may use less energy over all but is a home that can't breath on its own worse on the owner? I think there is such a thing as too tight.

What does TOH and many of the educated listners think?
Thank in advance

Re: Can you be too green?

Speaking from experience in the Great White north .... we have incredible standards of building "tight" homes. As you mentioned homes being sealed do have issues with indoor air quality from things like odors to actual chemical reactions to cleaning products and formaldehyde from furniture and the like.

About 17-20 years ago here ,HRV systems were becoming mandatory in the modern sealed homes and they do perform quite well. There is very little maintenance and do allow the home to "breath" nicely. For the most part the only maintenance is merely cleaning a filter.

IMHO ... having a "tight" home with a mechanical ventilation system is worth the energy savings and comfort.

Just my 2 cents.:)

Re: Can you be too green?

I love the concept, but also would have a fear of a "too tight" home. A tight home means recirculating the current air with a minimum of fresh air exchange.

This could become an even larger concern with homes with basements. With concerns of radon, release of flame-retardent chemicals from furniture into the air, not to mention paint and cleaning solvent fumes, it would seem that a "completely" tight home could become a danger to the occupants, particularly those with breathing issues such as asthma. The film buildup you find on the inside of your windows in your car, particularly new cars is actually the release of flame-retardent chemicals from the dash and upholstery. This same "release" could very well happen with the same type of chemicals in the home.

I think a way to periodically change the air inside the home with external air would be a preference.

Re: Can you be too green?

There is no doubt having a "tight home" is a good thing for energy efficiency.

With that comes the need to consider the quality of the air inside the "tight home" from the odors , problematic humidity and toxins that will accumulate.

A simple and a very effective way of dealing with this is the mechanical ventilation system. These are commonly referred to as air to air exchangers that are available in two configurations.

One configuration is simply to remove stale inside air meanwhile bring in fresh outside air .

The other configuration is the Energy Recovery Ventilator / Heat Recovery Ventilator (ERV/HRV) which does the same thing of removing stale inside air and replacing with fresh outside air while recovering up to 80% of the energy of the conditioned (heated or cooled) air being exhausted.

These units will exchange all the air in the whole house at least once every three hours ... so all the air in the home has been exchanged with fresh outside air 8-9 times in 24 hours. They are very effective in allowing the house to "breath" in a controlled energy efficient manner greatly improving indoor air quality.

links :






Another 2 cents that hopefully helps.:)

Re: Can you be too green?

can you be too green?

probally not but In this link I think canada is probally close to trying to be too green.


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