Do you have less floor space than you think? And are you paying for space you can’t use?
Have you ever considered how much of your “useable” space isn’t being utilized because it’s too uncomfortable? This is all too commonplace in buildings where the prime floor space near the windows is too cold or too hot.
Whether you are responsible for school classrooms, office spaces or residential living spaces, you can increase the usable space by upgrading the windows.
No one wants to pay for space that isn’t functional. In the commercial real estate marketplace, the rentable vs. usable space jargon refers to how much of the space under lease or purchased is taken up by building necessities such as common bathrooms, access hallways, elevators/stairs, HVAC, etc. vs how much is truly available for occupant uses such as living or office space, storage of occupant belongings, etc.
WexWindow SolutionsTM is an affordable solution that increases your useable/comfortable floor space year-round. A case study in a school building in White Plains, NY shows that after installing WexWindow glazing insulation panels in a test classroom, the classroom’s comfort zone grew to over ¾ of the classroom area during cool weather.
Memorial United Methodist Church (MUMC) has a school building wing which provides daycare and pre-K education to over 200 children year-round. MUMC teachers couldn’t fully utilize their classrooms because approximately 1/3 of their classroom area was too hot in summer or too cold in winter. This unusable area ran along the perimeter of the building, adjacent to the windows. But replacing their windows was cost prohibitive. MUMC’s leadership team worked with Joe Morris at the Metro IAF Clean Energy Initiative to find an affordable solution. Joe approached WexEnergy to learn more about the WexWindow Solution and see if it was appropriate for MUMC.
With funding provided by NYSERDA, Metro IAF contracted Transsolar KlimaEngineering to quantify the WexWindow Solution impact. The pilot study was performed in two adjacent classrooms, one fitted with the WexWindow Solution and one remaining as-is (the control classroom). The color-coded diagram below illustrates that the uncomfortable floor area of the Control Classroom is larger than the Pilot Classroom.
Preliminary analysis by Transsolar suggests that WexWindow PolarSkins will result in a reduction of 12 – 15% in heating and cooling demand. However, the benefit of the Window insulation panels is much more than that.
In fact, occupant comfort is a function of more than just air temperature. Comfort is also impacted by the temperature of the surfaces around us. This is just as important as air temperature because we exchange heat with these surfaces through radiant heat transfer all the time. We measure this with the “mean radiant temperature” (MRT). The MRT is the temperature of all the surfaces around you – walls, windows, ceiling, floor, furniture – weighted by how much each object “sees” you. This matters because your body exchanges heat with nearby surfaces by radiation (just like feeling warm near a sunny window or cold near any icy wall). If the nearby surfaces are much warmer or cooler than the air, you will feel warmer or cooler than the thermostat says.
In the pilot study, the MRT was measured in a 3’ band along the outer window-wall. The band of floor area in the control room measured 65o – 66oF. Yet there is significant improvement to the same 3’ band of floor space in the pilot room where the Wex panels measured 67o – 69oF. This translates to much more comfort at the same thermostat setting in the pilot room. In real estate terms, this means the uncomfortable floor area is reduced by about 40% as compared to the control room. MUMC staff noticed the Wex difference – the classroom was much more comfortable than the pilot room.
Since the retrofit was installed at the end of March 2025, the measurements were taken during outdoor temperatures of 46.5o – 53oF. During the 2025-26 winter season, measurements of both the glazing and frame insulation will be taken on colder days than the initial M&V period. We look forward to reporting the updated results in early 2026 when colder outdoor temperatures and frame insulation are expected to demonstrate even greater benefit of the full WexWindow Solutions system.
In summary, these results mean WexWindow installations result in more usable classroom space and better comfort for students and teachers while lowering energy usage and utility bills. And more comfortable students and teachers has been shown to lead to improved educational outcomes.1,2
1. Wargocki, P. and D.P. Wyon. 2006. “Research report on effects of HVAC on student performance.” ASHRAE JournalOctober 2006:22-28.
2. Wargocki, P. and D.P. Wyon. 2007. “The effects of moderately raised classroom temperatures and classroom ventilation rate on the performance of schoolwork by children.” HVAC&R Research 13(2):193-220.