Stone World

Focus on Indian Stone<br>Sandstone uplifts California school

August 16, 2001
Five families joined together to buy an old house in a depressed area of Marin County, CA, to begin the Oak Hill School. The single-family residence was then converted into a school for children with severe learning disabilities. Rundown concrete stairs and landings were torn out, and India Rainbow Teak Sandstone was brought in to replace it. According to Richard Parker, principal of 450 Architects, this was really a "feel-good" project.

"The old concrete and terrazzo stair and front porch veranda had heaved considerably through the years with the settlement of the earth," Parker said. "We removed all of the original treads set on the ground and put in a new concrete foundation for the stairs. We also built a series of new landings in the India teak sandstone, which provided a perfect complement to the clinker brick foundations."

The cause for the drastic settling of the earth on which the house was built was later discovered while researching the history of the site. A small stream that fed the into the San Francisco Bay was originally located on this site, according to Parker. "The Native Americans in the area would wash their clams in the spring and deposit the shells in a huge pile measuring approximately 300 feet long by 40 feet high," he said. "This old Indian shell mound is now the site of the Oak Hill School." Therefore, the shifting of the building's foundation over time as the earth settled was unavoidable.

In addition to the restoration and masonry work, the architects were concerned with taking the necessary safety precautions, ensuring that the site would be suitable for the children. "We upgraded all of the electrical and plumbing systems as well and took out the asbestos," Parker said. "We made sure that the interior included only earth-friendly materials due to the sensitivity of children to possible toxins."

When all of the safety concerns were addressed, and the building was brought up to code, it was time to look at the new space aesthetically. "Working with the original architecture, the landings were then complimented with teak stone," Parker said. "A pattern of this stone was incorporated into the landings. The kids just love it. We chose the rainbow teak because of its wonderful colors. Plain concrete would have been a missed opportunity."

India Rainbow Teak Sandstone was laid in tiles measuring 24 inches square. Three small landings and a large porch were adorned with this colorful stone.

All of the surface stone installation was completed by It's Hip To Lay Square. The tile setter, Dennis Lima, said his team, which included onsite designer Glen Boisselle and Sarah Schweitzer, was responsible for laying the teak sandstone on all of the landings and stairs. "We used a traditional thin-set installation with a 1-inch notched trowel because the stones needed to be close together," he said.

The heavy stone required additional men onsite to handle the 2-foot-square tiles. "We positioned every stone," Lima said. "We weren't just grabbing any stone and throwing it down. There was a pattern to it, and the right piece had to be out in the right place."

According to Lima, several patterns of veining and color variations can be found in the India Rainbow Teak sandstone. "Each stone had to be positioned in the right way because it would not be appealing to the eye if the grain or veins of the stone were all going one way and then switched in the middle," he said. "We did a dry run and set everything in place to create the full picture before beginning the actual installation. A lot of design work went into this project before we started laying the tiles down."

Despite the extra work, the restoration was complete within three months. This newly started school now has five to eight children in attendance for its one-on-one tutoring program. The current building can accommodate up to 14 children, and the school's goal is to attract as many as 50 children and build a new school at that time.