Today we hosted an "Open Walls" tour of the house. At this stage of construction, a lot of infrastructure is in place and viewable in the walls, under the floors or underground. Over the course of the next few weeks it will covered up and no longer visible.The tour was a tremendous success, attended by over 50 people. It attracted many silicon valley engineers who are interested in more efficient heating, solar energy, and more efficient water usage. A few architects and at least one contractor (other than this project's general contractor) also attended. Alas, I was too busy to put out a guest book for people to sign.
The high points of the tour ...
The Heat Dissipation Loops in the Pit
The 12 foot deep pit was the major feature alongside the north side of the house.
- The heat dissipation pipes for our cooling system were visible at the bottom, as were the aluminum heat spreaders both over and under the pipes.
Next, this pit will be partially filled in, and then the storm water dissipation and water storage pipes will be installed.
The Second Floor
The first tour group visitors came up to the second floor of the house at 2:30pm on a fairly sunny afternoon.The abundant use of radiant barrier was plain to see. There was no other insulation installed yet. And yet it was immediately noticable that the temperature inside was actually very pleasant: it was not hot at all.
The radiant barrier fulfills several functions in the slanted roof: it serves as an insulation stop, so that insulation that is blown in will not go thought the wood roof shingles, it serves as a radiant barrier directly under the skip sheathing to which the wood shingle roof is attached, and it serves as an insect barrier, so that wasps or bees don't build a hive in the stud bays (we discovered a few when the walls were opened).
The Wine Cellar
Many wine cellars are designed with expensive refrigeration systems, and can keep wine at 55F so that bottles can mature over the course of 100 years. These refrigeration systems cost a lot of money to buy and operate.My goal is to build a wine cellar that can hold decent wines at 60F, aging them over a period of 10 to 20 years, so I can enjoy them during my lifetime :-)
This cellar is designed to take advantage of relatively stable (60F) temperature at 12 feet of depth - which is the yearly average temperature of the San Francisco Bay Area. To do this well, the cellar is built deeper into the ground than the rest of the basement.
In spite of the lack of insulation, no door, and it being the end of the summer, the cellar temperature was 62F during the tour. I don't believe there will be any trouble achieving the target temperature of 60F.
Discussions
There were some good discussions regarding the installed shower heat reclamation plumbing, the two examples of more efficient insulation and heating for the tile floor areas, and the frustrations with thrying to get greywater irrigation approved - even in this water conservation climate.
Visitors got to hear about (and critique) some of the planned experiments in heating and cooling. I welcome this feedback, and endeavour to produce data over time to show how well things actually work.
Tour Site Placards, as an online presentation. Some photos taken by a visitor.
Thanks
I'd like to thank my wife Patti who took care of tasty refreshments for the visitors. I'd also like to thank my contractor Bernie and his staff for doing a great job presenting a clean and safe site, for last minute help putting up the informative signs and especially to Bernie for being available to answer many questions. Finally thanks to my friend Andy, a mechanical engineer, for answering questions for people who didn't quite catch the first tour but couldn't stay for the second.
