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Extreme Remodel

GBA Editor | Posted in General Questions on

We are completing a small remodeling project where we took a 1956, 1100sf home and added 355 sf.

The house started as a HERS 190 and tested out after the work at a HERS 5.

I think that we may have achieved a new record for remodels. Does anyone know of an example that comes close to these numbers?


– Ron

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  1. GBA Editor
    Martin Holladay | | #1

    How big is your PV system?

  2. Ron | | #2

    5.4 kW

  3. Riversong | | #3

    Sorry, Ron, but the PV doesn't count as an efficiency improvement.

  4. Ron | | #4

    Robert ,
    The PV is not what I wish to brag about. The improvements to the building envelope is what I am most proud of. I went from over 3000 cfm @ 50, to 730 cfm50 while adding to the size of the home. I am still waiting to hear back from my HERS rater, but it looks like we are around a HERS 40 w/o the PV system. It seems that going from a 190 to a 40 is still better than I have seen around town. I am trying to find other remodel examples to better gauge our success

  5. John Brooks | | #5

    Here's a "ZERO" remodel

    I hope your PV looks better ;--)

  6. Ron | | #6

    I have been looking at this house, but I have not yet found before and after HERS scores (I have a call into the Architect about it).

  7. Jesse Thompson | | #7

    We're working on one right now that is very similar, 1,200 SF 1962 single story ranch w/ 500 SF addition, 3000+ CFM50 to start. It's down to 710 CFM50 pre-cellulose and drywall, projected HERS ~40 in the end (no renewables):

    One tricky issue is that a deep energy retrofit on a rehab like this becomes so invasive that on some level it's getting very close to new construction. It doesn't impact an undeveloped plot of land in the same manner as new construction, but it's not just remodeling...

  8. Ron | | #8

    Your project does seem quite similar. That said, we were not that invasive. In fact the homeowners lived in the house the entire time (except one night in a hotel when spraying foam). This had a big impact on the affordability of the project for them.

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