Another Climate Zone question
I’ve done some searching around the site and the web and cannot find the info I am looking for.
I will be building a home in Jefferson (Jeffco) County Colorado, which is listed as a 5B zone. My problem with this is that Jeffco has such a large elevation range. The lowest elevation is 4,987 ft and the high is 9,127 ft. The weather and temperature in the county can vary by a lot, like it could be snowing in one place and 75 degrees in another at the same time (you have to know Colorado, this can and does happen all the time). Jeffco covers open plains up to rugged mountains.
I have tried basing it on the zip code, but my zip code covers such a large area, that the elevation difference in just the zip code can change by 3,300 ft.
I’ve thought about using the next county over, Park County, but that jumps to zone 7B. The climate zone maps are crazy in Colorado. How can you go from a zone of 5B to 7B just based on a line on a map?!
I’ve also learned that the zones are based on heating degree days.
Here is how it is calculated:
Heating Degree DaysThe degree-day measurement is the difference in temperature between the mean (average) outdoor temperature over a 24-hour period and a given base temperature for a building space, typically 65°F
The home I want to build will be at the upper end of the elevation, 8,400 ft. I’ve tried looking for temperature data, but there isn’t a weather station close to my area and I wouldn’t know how to get the info from it if I could.
So how would one go about finding out what climate zone I should build to? I understand that I could just go to zone 6B can call it good, but I am a data guy and don’t like to just go larger to be safe. This is also important to me because I want to use exterior insulation and need to know how what percentage of R value I need on the exterior of the building for both the roof and walls. Zone 5 is 30%, while zone 6 is 35%. This will also affect my Manual JSTD’s. This can and will drive the amount and location of the insulation, double or triple windows, and the size of the heating/cooling equipment. So there is a real cost difference depending on where I end up.
Thanks for any help.
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