Transylvania County Schools

Pisgah Forest Elementary School DTW Piping

In 2021, we were hired to evaluate and replace the air handling units at Pisgah Forest Elementary School in Transylvania County, North Carolina. While on a site visit for that project, Bob Wiggins, PE, a member of our Mechanical, Electrical, and Plumbing (MEP) team, noticed the existing dual temperature water piping system (two-pipe system) was failing due to corrosion. As he was looking at the air handling units, he saw that the piping connections were visibly deteriorated. Upon further inspection, he learned the deterioration existed throughout the piping system, which was a severe safety concern. The pipes carry chilled water (45F to 55F) and heated water (140F to 180F), and so a water leak was a safety risk for the school’s people and property.

After the site visit, Bob wrote a letter to the facility’s maintenance director and school board stating that the school needed to urgently replace the piping system. Due to the urgent nature of the situation, this letter was sent before we were under contract. It was constituted as an emergency project and was quickly approved. Replacing the piping system took priority over the air handling units project.

In the 1980’s, schools were not typically air conditioned. Bob recalls being in school as a kid and not having air conditioning in the classroom. There were times when the teachers would take a break from teaching because it was too hot to learn. When schools started getting air conditioning, they were typically given a two-pipe system. This system tended to perform well in schools, mainly because most schools had a double-loaded corridor layout–meaning there was one hallway with classrooms on both sides.

However, as school designs became more modern and complex, the two-pipe system was less effective because different parts of the building had varying air conditioning and heating needs. The two-pipe system at Pisgah Forest Elementary School was installed in 1989, which was right before four-pipe systems became more typical in schools.

Just before the start of the 2024-2025 school year, we finished installing the four-pipe system in Pisgah Forest Elementary School, and we are planning on several upcoming projects that will continue to improve the school.

First, we will replace the air handling and VAV units with units that can take advantage of the four-pipe system. Then we will replace the lined duct work with wrapped (externally insulated) ductwork. Lined ducts are optimal locations for mold growth, which creates a problem for indoor air quality, so we want to eliminate that potential issue. Finally, we will improve access to the air handling units as the current access point is inconvenient and dangerous. We anticipate picking up these projects again in the summer of 2025 and do not have an estimated project finish date.