top of page

Window 107

The middle panel depicts Architect James Renwick (1818-1895) showing the plans of the cathedral to Archbishop Hughes (1797- 1864, to the left) and Cardinal McCloskey (1810-1885, on the right). In the background is Nicholas Lorin of Chartres (1833-1882), maker of 27 of the windows installed in the 1870’s and 1880’s.

St. Patrick's Cathedral 

New York, New York 


Zubatkin Owner Representation

Murphy Burnham & Buttrick Architects

Structure Tone 

St. Patrick's Cathedral is a Roman Catholic Cathedral in Manhattan, New York. The cornerstone was first laid in 1858. The restoration efforts involved  upwards of 25 different firms. Botti Studio was tasked with refurbishing damaged windows, replacing protective glazing, and installing our interstitial venting system.  Botti began work in 2011 and the project finished in 2015. 

Protective Glazing
The Research

With any project of this magnitude and historical importance, alot of research is done on the front end. An origional sketch by James Renwick  was found detailing the glass, and the installation of the protective glazing. The origional interstitial space between the glass adn the protective glazing had no venting, which can be deterious for the glass. 

Samples were prepared with Landmark Facilities Group to understand the interior dew point day by day. Vented windows, and unvented windows generally seemed to perform the same. Luckily there is low humidity, and there was low risk for corrosion of the paint. It was agreed that windows would not be tampered with where it wasn't necessary, so we chose a more targeted approach. We would focus only on windows that needed the interstitial venting the most. We figured this out by employing a shadow and solar study. 

The Enviromental Simulation Center / Michael Kwartler and his colleague Aihan Polat conducted this site specific shadow study to measure the increased temperature in the interstitial space throughout the day. We also wanted to know which windows were subject to the most direct sunlight. 

Venting, Re-Leading, Restoration and Installation

We meticulously inspected the windows looking for problem areas: cracked glass, missing pieces of glass, rust, missing putty, bowed glass, poorly repaired glass, and deteriorated leading. 

With the results of the Solar Study, it was decided that we would do targeted venting of south, east and west facing windows with extra focus on large traceries and tops and bottoms of lancets. All venting is invisible from the interior and reversible. 

A new 1/4" thick protective glazing with UV interlayer was installed over the stained glass panels vented of interstitial space to the interior of the cathedral. The lead cames are designed to match the original segmentation. 

The Finished Restoration and A Special Visit 

The project was finished in September of 2015, which coincided with a visit by Pope Francis to New York City. 

Pope Francis visits NYC on

September 24th 2015

top of st pats
bottom of page