1926 House- Windows & Walls
I have a 1926 house in Northern California. The exterior walls are 4″ clay block- unfilled- 1″ exterior stucco and 1″ Lath and plaster interior. I have a variety of windows ranging from wood double hung, wood casement and metal casement. All single pane. I’ve looked at replacing them but can’t really afford to do that yet I’ve been thinking about weatherstripping them but am wondering with the low R-Value windows and walls if it would really do any good. Or even if EE windows would really help. I realize it might help some, ROI could be 20 years. Any advice would be appreciated.
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Replies
Jeanne,
Installing replacement windows is almost never cost-effective if your goal is to save energy. In your mild climate (assuming your house isn't in the mountains -- somewhere with very cold winters), it makes even less sense than it does in Vermont.
It may make sense to install storm windows on your single-pane windows. If some of your windows are drafty, installing weatherstripping definitely makes sense.
If you want to have an idea of the types of energy retrofit measures that make sense for your house, you should hire an energy rater certified by BPI or RESNET to perform an energy audit of your home. If you can't afford to hire someone, contact your local electric utility or gas utility. Some utilities offer free or subsidized home energy audits to their customers.
Jeanne,
Would you tell us a little bit about why you are concerned about the windows - comfort, looks, energy bills? There may be some relatively inexpensive DIY things you can do that will help with the issues that are most concerning to you.
Are there other things you are thinking about doing to the house?
Not just storm windows but LOW-E storm windows can make a real difference in both comfort & efficiency, independing of wall & attic R-issues. Low-E storms cost more up front than clear glass storms, but they perform sufficiently better that the pay-back is sooner than clear glass storms. (Under 5 years in most US climate zone 4 -6 locations.)
Harvey makes the tightest storm windows in the biz and have a hard coat low-E option, but the "Silver" or better series low-E Larson's sold through box stores don't suck from an air leakage point of view, and are worth the upcharge from the "Bronze" series.
If the blocks are the hollow terra-cotta "mission" block the R-value of the stackup would be R2-R4, whereas the R-value of a wooden sash single pane is about R1. A clear storm would increase the window to about R2, but a low-E storm brings it up to about R3.