In 1982, Thermolite installed its window system in one of the largest buildings in South Bend, Indiana and showed spectacular results. Not only was there a significant monthly savings but the City did not have to spend significant investment dollars to properly heat or cool their building. Instead the Thermolite Window System was put in place which reduced the cold drafts in the building and reduced the need to run BOTH boilers at FULL capacity.
Stories like this should remind building envelope advocates not to forget the deferred capital cost OR reduction in capacity in the calculation of ROI. In every large building case, the savings in capital needed to upgrade the heating and cooling system more than pays for the window upgrades PLUS there is an ongoing annual savings of over 20% per year.
Large single glazed buildings which need window and envelope upgrades are often of the vintage where the chiller and boiler need work as well. This is a reminder to all the building owners out there to look at these at the same time and use interior windows to multiply your project return on investment.
Take a look at what the facilities manger said here.
