A couple of months ago, I visited an early adopter of green remodeling in the Bay Area. She has been making changes to her home since over a decade ago, before energy efficiency gets on the minds of most people.
Starting in the late 1990’s, she had windows changed to dual pane units, installed attic insulation and replaced her wall heating units with a central heating and air conditioning system.
Since then, she replaced her roof with a cool roof, which reflects more solar heat to keep the house cooler. Over the roof, she had 1.8KW of solar PV panels installed. She had the underfloor insulated. Still feeling that not enough hot air coming into the house, she had attic ducts sealed and insulated to reduce heat lost into the attic. She also installed an electric tankless water heater. These modifications made her house a lot more comfortable which is the primary reason she did the work. However, she recognized that conservation was a nice benefit too, and while these upgrades required upfront cost, she figured that the operating cost will be less in the long run.
A less common green measure she took was to install a rainwater harvesting system. She first installed 2 tanks to store 2500 gallons of rainwater captured from the roof. With a small pump and a series of filters, she is able to use the rainwater for all her laundry all year around. A separate small capacity electric tankless water heater next to the washing machine provides point of use hot water for laundry. The two electric water heaters require 240v electricity supply and so triggered an upgrade of the electrical and fuse boxes. Later she added 2 tanks for another 3100 gallons of storage used for irrigating her drought tolerate front yard. Since the front yard is at a slightly lower level than the tanks, gravity alone does the irrigation job.
Cellulose is the preferred product for insulating wall cavities of existing homes. When installed with the dense-pack method, settling in wall cavities is negligible and air flow in wall cavities is reduced significantly. It performs very close to its stated R value unlike fiberglass’s performance which is affected greatly by the precise fit of the batts in their cavity.
Cellulose insulation is also great for loose fill or open-blown attic applications. When installed at proper depth it creates a continuous blanket of insulation which eliminates loss resulting from the poor R value of timber framing members (thermal bridging).
Noise reduction is also done well with cellulose, achieved in three ways. The first is that cellulose completely fills cavities leaving few air pockets for sound to travel in. The second is the cellulose materials ability to trap air. The significant difference between noise reduction with cellulose and fiberglass is its density. Cellulose is approximately three times denser then fiberglass. This helps deaden the sound through walls and between floor levels.
What an inspiration this woman is! And what foresight, to begin so many years ago. I wonder if she would consider giving tours!
Linda, I forwarded your nice comments to her. I hope she would consider it.