Wolf House

Over the weekend we spent the afternoon at Jack London State Park. I had read about the ruined Wolf House but had not seen it previously. Ruins are fascinating because they are so symbolically charged. There is the obvious connection with mortality; the structure, like an old person, at the end of its life. But the ruin also embodies heroic persistence against time and nature. The remnants of the Wolf House survived a destructive fire and while lichen grows and nature tries to reclaim the stone walls, they resonate defiance. Preserving a ruin is perhaps one of the most philosophically challenging aspects of the profession.

Placerville City Hall

The historic Placerville City Hall is for sale. Check it out!

HPC Meeting - 20 May

On Wednesday at the San Francisco Historic Preservation Commission meeting there were some interesting discussions. First there was a staff report about a new permit tracking system. This system is still several years away from becoming a reality so it was sort of a tease to be talking about it now!

This was followed by another staff report about 1268 Lombard Street; a cottage built in the 1860's. The owners applied for and received an emergency demolition permit a few months ago under suspicious auspices. Highly publicized, the demolition has initiated several potential new ordinances including one for blight and one for vacant buildings. During the meeting it was suggested that one of the problems with the emergency demolition process is that the owner provides and pays for the structural engineer. This obviously compromises the engineer and prevents an objectively written report. The HPC plans on writing a letter about this item to be discussed at the next meeting (June 3).

In his President's Report, Charles Chase announced that the July 1 meeting would be canceled and that he wanted to calendar a discussion about the scope of staff review.

Items 5 and 6 were removed from the Consent Calendar and item 4 a Certificate of Appropriateness for a building in the South End Historic District received an unanimous vote. Item 5 was a Certificate of Appropriateness for a building in the Northeast Waterfront Historic District and the discussion centered around windows (one of my favorite topics!). The Commission agreed with the staff analysis that the true divided lite windows be a condition of approval.

Item 6 was particularly interesting to me as I briefly worked on the Muni Substation (Landmark No. 105) several years ago. The San Francisco Redevelopment Agency has been unsuccessful in restoring this empty, deteriorating building. They will no longer have jurisdiction over the building in the coming months and it will soon be transferred to the San Francisco Real Estate Division. A major concern is that the building will be even more neglected than it already is. I have felt for a long time that the Muni Substation on Fillmore Street is the most endangered of the Landmark buildings in San Francisco. The proposed project heard at the Commission meeting was to remove a non-historic shed addition and unfortunately did not include any additional restoration work. The vote was unanimous. By the end of this item (3:00pm-ish) I had to leave the hearing and do not, at this time, know the outcome of the final items.

News

There is an awful lot of demolition in the news at the moment. I've been in denial about the demolition of Paul Rudolphs Sarasota School. But sadly it will be gone by the end of the summer. And surprisingly there is an I.M. Pei-designed "brutalist" church in Washington DC that may get demo'ed too. This morning I read a rather sardonic article about the uncertain future of "the crappiest building Mies ever designed." It was actually kind of funny. With all this needless destruction it is always nice to hear Prince Charles talk about the saving our built environment!

Saving a Giant Sequoia

A small entry addition for my parents vacation house in the Tahoe Area was the first project that I completed on my own time. The house was L-shaped with the original entry at the crux of the L; a good distance from the road. In the winter, getting to the door was a challenge! The end of the leg that was closest to the street was octagonal. Designing a compatible addition to this marvelously angled construction tested my geometry skills. Another obstacle was a Giant Sequoia growing close to where we wanted to build. With some research and careful construction techniques this beautiful tree continues to thrive years later, much to my joy.

Little gas station

This is currently one of my favorite buildings in San Francisco. It is located at 16th Avenue and Irving.

Preserving Buildings as a Sustainable Strategy

Tuesday evening I attended a lecture entitled Preserving Buildings as a Sustainable Strategy at the San Francisco American Institute of Architects. I was overjoyed to hear a structural engineer, David Cocke, talk about preservation in such a positive way. In addition, he reiterated a skepticism with the Leadership in Energy and Environmental Design point system that I share. The lecture introduced me to two great ways to worry about the future of our planet; an EcoCalculator, and an Embodied Energy Calculator.

On a side note the San Francisco Young Preservationist Network (or Heritage YP) is touring the rehabilitated Levi Strauss & Co factory, now Friends School. Though I can't attend, those who can, should!

Historic Preservation is About San Francisco's Future

The article in the San Francisco Chronicle last week written by C.W. Nevius did not surprise me. I am used to his negative tone and uniformed remarks about historic preservation. However I was very happily surprised by Jack Gold's rebuttal article several days later!

Efflorescence - Part Two

In many cases efflorescence is more of an aesthetic issue and tends not to cause major damage. None the less, it should be removed once the water source has been averted. The removal process will range from easy to difficult. The thing I find ironic is that water is often used to wash the efflorescence away. Water was the problem to begin with! If at all possible, try to avoid using water to remove efflorescence. Start with a medium bristle brush and gently brush the salt residue off into a container for disposal. This technique achieved a satisfactory result on the vertical surfaces in my basement as seen above. A damp cloth will work on some surfaces, for efflorescence that is not responding to brushing. This worked well for me on the horizontal concrete.

There are even more aggressive ways of removing efflorescence including detergents and acids. However it is important to weigh the benefits versus the detriments. In general detergents and acids are harmful to the environment and specifically can be damaging to building materials. It is hardly worth the effort of removing the efflorescence with acid, if the acid also removes the surface of the building materials we want to remain. In my opinion, aggressive cleaners are only appropriate when stubborn efflorescence appears on an important character defining feature or if it is causing damage.

Efflorescence - Part One

Efflorescence is a surprisingly complicated phenomenon that has existing in our built environment for thousands of years. On the surface of it, efflorescence is simply water traveling through a material, such as masonry, dissolving alkalis which solidify again once the water evaporates. When evaporation happens at or near the surface of a material the alkalis are revealed as a white powder. (Note: Not all white residue on buildings is a result of this type of efflorescence. This is simply a common kind.)

After a flood in our basement, efflorescence appeared on the concrete and I shall use it to explain investigative and remedial processes. In most cases when one comes across efflorescence it is without previous knowledge of the source of water. The first step is always to try and figure out the path of travel of the water. This is not necessarily easy and writing out a list of possibilities is always a good idea. Although the flood in my basement covered a large part of the floor, efflorescence only appeared in one area. It is important to remember that efflorescence can only occur when alkalis have been dissolved into the water. You can still have a major water problem without efflorescence being the result.

Determining the source of the alkalis may help find the source of water. These "salts" can come from Portland cement, sand, soil, within a brick, or from the water itself; usually from a combination of sources. If the water that flooded my basement had alkalis in it, then most of the flooded region would have revealed efflorescence. In the same way if the alkalis had come from the concrete mix, then I would have seen more affected areas. Instead efflorescence was located along a crack in the floor. It is pretty clear that the salts came from the ground below the concrete that has been brought closer to the surface through the crack.

Once the source of the water has been remedied the efflorescence can be removed... To be continued!

Virginia Tech

On Friday I had lunch with a former professor from Virginia Tech who was in town for the AIA convention. She shared some news of Blacksburg which has changed quite a bit since I was last there, ten years ago. Later, our conversation inspired me to looked back over some of the projects I worked on in college; when I first started thinking about how to integrate new design into the existing built environment.

AIA National Convention

The American Institute of Architects National Convention was held here in San Francisco last week. 800 vendors filled the entire Moscone Center along with 20,000 attendees. I volunteered at the convention helping people get to where they needed to be. Questions about what to see with a brief amount of time made me think carefully about the places that make San Francisco. These are some of the places I think are core to experiencing the City:

• City Hall
• Alamo Square
• Castro Theatre
• Crissy Field
• Haas-Lilienthal House