NAR's public consumer advocacy website is HouseLogic. This month they are featuring an interesting twist to increase consumer interest in energy efficiency makeovers. They've done some fantasy-inspired estimates for three big energy efficiency imp...
Fantasy aside, not sure I would replace historic windows, and for the average real house, today, in the US, the payback for insulation and air sealing would sure be a lot higher.
Interesting way to get the conversation started though! What do you think about the story?
The Downtown Abbey HEP Partnership - I'm in
Interesting. Can you send me the link you used? Methinks their math is way off somewhere! Thanks.
Personally I don't think costs are a good way to evaluate overall efficiency.
For a building like this it will never be 'efficient', too many windows so a solution is to supply its heat w/o using the grid and that's fairly easy using thermal-fluids and storing them in insulated tanks for use on-demand to warm a room.
This means no grid power is needed to heat the whole building, one wouldn't necessarily need to replace the windows for this particular case.
So this would take some trough collectors on the roof heating the thermal-fluid system, it's similar to using steam except with the fluids they don't boil and don't freeze so the drawback is pumping as a need for power but none needed for the heat.
Doing this means the "costs" of heating the building will be the capital costs amortized over the payback and a small amount for maintenence, huge difference looking at it this way to pay-by-the-watt heating even with new windows.
Is there enough roof area on this "whole building" to come close to supplying enough BTU's? Is there enough acreage on the estate to do that?? How many millions of BTU's per hour is needed? If the building is 40,000 ft2, and it loses 30,000 BTU/ft/season - that is over a billion (with a B) BTU in a season.
Maybe it has it's own coal seam on the property, or maybe their 1,000 acres of woods could come into play.
Next to impossible to make this efficient on any level. Reduce, reuse, recycle. Reusing and recycling the existing building materials may be the way to go.....from an energy efficiency perspective....
This building is a great example of something so lossy it really should get some solar-gain into the equation, some alternative to collect solar-thermal stored to use for the daily cycle and get off the need to burn anything for heat most of the year.
As a practical matter probably the only major efficiency measure would be air sealing. I bet there would be some good opportunities.
How many truck mounted blower-doors would it take to test that place? Think of the effort just to check the doors and windows and make sure all the interior doors were open. And the fireplaces covered.
The calculator is here:- http://www.ggf.org.uk/energy-savings-calculator. It uses metric units.
This problem requires a pragmatic approach. My suggestions in order are:-
1. The installation of a biomass heating boiler system for heating using the estate renewable timber resource.
2. A solar hot water system probably roof mounted.
3. Gradual replacement of the glazing units with slimline warm edged DG units - 11-14mm. thick.
4. Attention to drafts at windows, chimneys, etc.
There probably isn't much scope for internal upgrading of wall insulation in this case but in other situations thin insulation systems such as Multifoil or Spacetherm can be used provided extra attention is given to ventilation of the existing structure.