We were correct in our hypothesis that the Watzek house has a greater than normal amount of infiltration. The Blower Door experiment showed that the rooms tested were slightly leakier than estimated.     However, our hypothesis that more heat is lost through infiltration than through conduction was incorrect.  Both the hand calculations and Energy Scheming show that more heat is lost through conduction than through infiltration, but the results for each disagreed on the proportion.  Our hand calculations show that infiltration contributes only a minimally to the overall heat loss. The windows were the single greatest factor in this calculation.  Energy Scheming, on the other hand estimates that infiltration plays a larger role in heat loss than our hand calculations suggest.

Design Lessons Learned
 
 

Our calculations and the energy scheming program also show that a significant amount of heat loss may be prevented if storm or double paned windows are installed.    Even if infiltration was a larger factor in heat loss, storm windows would be less intrusive than any method of preventing heat loss through infiltration.  Infiltration is very hard to fix in a house, it is much easier just to build a relatively tight building than to fix it later.  This goes double when you consider that this house is a historical house, many of the parts of it cannot be found today.  Other methods like blown in insulation would require damaging the irreplaceable walls in the Watzek House.  Making the windows smaller in the dining room or the living room would greatly diminish the wonderful light qualities that those rooms currently have.

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