[Greenbuilding] tight additions open to drafty houses

Eli Talking elitalking at rockbridge.net
Wed Mar 13 16:40:38 CDT 2013


I have a client I am trying to "Deep Energy Retrofit" their old house. 
Whether they do that or not, I think it is important to make the addition to 
the new standard of tightness.  However, it evaluating the value, I am 
confused by the impact of being open thermally to the 1930+- un-insulated 2 
story clapboard house.  If not thermally separated, will the tight 
construction of the addition get air from the drafty main house.

Though a Foyer and hallway needs to open to the old house, perhaps the 
bedrooms, bath and closets could be separated by sealing and insulating 
interior walls.  I would think that since the old house will be conditioned 
to comfort, insulation is secondary to sealing.

Would that separation be needed to take advantage of ERV.  Maybe a simple 
timer on bath vent could deliver the fresh air from drafty part of house.

I am a little on thin ice in that thermal efficiency is not their agenda. 
However, I feel an ethical responsibility to build new to a high standard. 
To build to the common practice is to build obsolete without consideration 
of the embodied energy that will be consumed.  If we build to reduce and 
ideally eliminate the consumption of non-renewable energy, we have not 
depleted the resource used to make the house until the house is destroyed.

Eli 






More information about the Greenbuilding mailing list