Laboratory Testing for Minton Tile Repair

Bethesda Terrace, Central Park

The Bethesda Terrace and Fountain overlook The Lake in New York City's Central Park. The fountain is located in the center of the terrace.The terrace is on two levels, united by two grand staircases and a lesser one that passes under Terrace Drive. They provide passage southward to the Elkan Naumburg bandshell and The Mall at the center of the park.


New York, New York

Architect & Date

Calvert Vaux, 1859


Central Park Conservancy

Services Provided

ICR conducted laboratory testing to help determine patch compounds and coatings for the repair and replacement of the Minton tiles in the ceiling.

•Design and execution of laboratory testing program on composite tile repairs
•Design and execution of laboratory testing program on replacement tile coatings

ICR designed laboratory testing programs first in 1998 and then in 2005 to address repairs for the Minton tiles at Bethesda Terrace. The first round of testing investigated the performance of potential composite repairs for the tiles – two cementitious mortars and two epoxy-based materials incorporated into broken pieces of the Minton tiles – coated with both inorganic- and acrylic-based coatings. The test panels were subjected to accelerated testing by QUV-Spray and freeze-thaw cycles and evaluated visually for any changes including water repellency by water drop test. 

The second round of testing researched coating performance on epoxy-based composite repairs after accelerated testing in a QUV-Spray machine. The results were evaluated by adhesion of the coating to the substrate through tape test and color change by spectrophotometry, conducted before and after accelerated testing.