Best use of extra funds for high performance options
We are in the process of building a custom home in Denver Colorado, Zone 5. 4215 Sq Ft. 4-bedroom 4 bath, with a conditioned crawl space. Main floor has an in line living room, dining room, kitchen. Living and dining are vaulted, kitchen and rest of main floor drop to 10 ft. ceilings. Second floor has two bedrooms and bonus room, 9 ft. ceilings. 2×6 construction, zip sheathing on walls, vented roof. Walls will be R-23, Ceiling R-50, Floor R-38. I expect a blower door score of 1.5 ACH50 or better. HERS model states we will have a score of 57. My builder is a custom builder but I’m driving the high-performance aspect of this build.
We break ground in June and still have a couple decisions to make as to where to utilize about $40 to 50K of extra money. Options include the following:
- Upgrade windows from Anderson 100 series (.26 U-Factor) to Alpen Zenith ZR-6 series (.14 U-Factor). This would also include a 16 ft. 4 panel slider in main living room. Upgrade from Windsor Pinnacle Clad (.30 U-Factor) to Alpen Zenith (U-Factor .19). Around $30K increase. Almost forgot, all windows are fixed (thanks Steve Baczek) except the required egress in 3 bedrooms and the master has a door to patio for egress.
- Add closed cell spray foam for a flash and batt insulation on walls and roof. Around $19-25K increase
- Add Zehnder ERV Around $15K increase
- Use Zip R6 or Zip R9 on exterior walls. Around $20K to 25K increase
- Use AeroBarrier. Haven’t had an estimate but the guess is $5 to 10K.
HERS rater stated exterior insulation, Zip R, doesn’t make much difference in score. Windows would probably help HERS score the most, but he hasn’t modeled all the above scenarios.
If there is something else, I should consider please let me know.
Feedback by most to least important is greatly appreciated. My goal is comfort, which I realize is subjective, but I don’t want to experience hot or cold spots and with three children under 6 air quality is important.
Thanks in advance for any feedback.
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