Tenley Library Roof Maintenance FAQ

Tenley Library Roof Maintenance FAQ

Q: How old is the Tenley-Friendship Neighborhood Library and what were the initial construction costs?
A: The Tenley-Friendship Neighborhood Library opened in January 2011. The 21,500 square foot building cost $18 million to design and build.

Q: What sort of roof does the Library have?
The library roof has several components, including a vegetative green roof, mechanical systems and a large skylight. It is not accessible to the public.

Q: What is a vegetative green roof?
A: A vegetative green roof is a layer of plants installed on top of a building. Green roofs help improve water quality by slowing the release of storm water into the city’s sewer system and by filtering the water before it is released. Green roofs also lower cooling costs for the building, reducing the heat island effect and increasing urban biodiversity.

Q: How long has the Tenley-Friendship Neighborhood Library experienced leaks?
A: Leaking was first reported during a heavy rain in April 2011. It was determined that the source was the gutters associated with the skylight. The Library has worked to address the sources of the leaks.

Q: What has DC Public Library done to fix the leaks?
From 2011 thru 2014, because there were warranties, the Library worked with the original architect, general contractor and subcontractors to analyze and fix the problem. The first problem to be identified was lack of drainage caused by debris accumulating in roof gutters and drains. The Library took the following steps to fix the drainage:

  • The Library installed gutter guards and increased the recommended maintenance cleaning of the gutter system from twice a year to monthly.

  • The Library installed gutter wall covers on the north and south sides of the gutter-box.

  • Frequent cleaning of the drains became part of the maintenance protocol, including cleaning in anticipation of heavy rains, but the leaks recurred. Contractors were still unable to pinpoint the exact source.

  • In 2015, when the warranties on the skylight components expired, the Library engaged a new roofing company to analyze the problem. They determined that the gutter needed to be repaired, and they applied a waterproofing membrane. There were no leaks from spring 2016 to spring 2017.

In 2017, the Library hired a new company to conduct a full assessment of the building envelope and the roofing system to determine the source of the leak and to correct the ongoing issues. Work began in the fall of 2017 and was completed in March 2018 at a cost of $184,000. Subsequently, in May 2018, there was a leak caused by clogged drains.

Q: If the skylight was repaired, why is the building still experiencing leaks?
A: In July 2018, there was a leak caused by a tear in the green roof membrane.The Library has installed a temporary cover on that area to stop any leaks, and is also working with the roofing company that holds the warranty to complete a permanent repair.

Q: How many days has the Library been closed due to the leaks?
A: Since the library opened in 2011, the Library has closed on three occasions for a total of six hours and 15 minutes.

Q: Have any of the books or materials been damaged as a result of the leaks?
A: No books or other library materials have been damaged.

Q: Have any users or staff been hurt due to the water or methods of containing the water?
A: No library users or staff have been hurt or injured due to the issues with the skylight or green roof.

Q: Who designed and installed the roof on the building?
A: The building was designed by The Freelon Group and R. McGhee & Associates and was constructed by the Forrester Construction Company. Forrester subcontracted installation and waterproofing of the skylight to Prospect Waterproofing and Galaxy Glass.

(Updated: September 27, 2018)