The yellow part of the infrared image of a window shows the warmest, the blue areas indicate coolest, providing accurate information about heat loss, and what needs doing to prevent it.
Outside, we shuddered in the cold, still gobsmacked at the beautiful distinctive architectural elements, while Alex and Shannon evaluated areas of good heat retention and heat leak. Data? You bet. An informed and aware homeowner? Ditto.
The more we looked, the more we saw. The beautiful rippled effect of the early window glass with the snow sparkling outside, was a stunner. One pane of glass bore a swoosh like a spoon mark on cake batter - the final flourish of the glass pourer onto the sheet of cooling poured glass?
How could anyone toss that kind of beauty and history into architectural salvage - or the dump?
Shannon has sent links to three more videos in the series In Praise of Older Windows, which she is creating with the assistance of Andrew Skuce. Shannon demonstrates the relative thermal efficiency of old wooden windows over modern vinyl replacements, and argues forcibly for retention of original windows to preserve the heritage character of older homes.
The second video features a visit to an Edwardian gable-front house with its high-performing 110 windows.
In the third video of the series, period window expert Alan Stacey explains the parts of wooden sash windows, and how to maintain them (or replicate them) to meet or exceed the thermal efficiency of modern replacements.
The fourth video talks about the heat that can be maintained by simply installing curtains.