The Challenge
Stuart had invested years into creating a unique outdoor entertaining space. A beautifully built garden outbuilding known affectionately as Angel’s Asylum. With six large windows and a south‑facing aspect, the room was designed for year‑round enjoyment: barbecues, pizza nights, New Year’s parties, and even gatherings for his son and friends.
But the glass created a problem.
Despite blinds, despite careful planning, despite being a self‑described “data man”, Stuart found the room regularly overheated. His remote thermostat frequently triggered alerts above 27°C, even on moderate days.
As he put it:
“We set some alerts above 27° and actually found that it went above 27° quite frequently.”
The solar gain wasn’t just uncomfortable, it was preventing the room from performing the way he intended.
He needed a solution that:
- Reduced solar gain significantly
- Offered an aesthetical appearance to the building
- Avoided the mirrored, reflective look of traditional films
- Delivered measurable, data‑backed improvement
The room was perfect in every way except temperature. That had to change.
The Vision
Stuart and his wife wanted a space that stayed comfortable even on hot days, without compromising the open, transparent feel of the windows.
He explained “We wanted something that was transparent… we didn’t want it looking like some kind of mirrored secret building.”
The brief was clear:
- Maintain the natural look of the glass
- Reduce heat dramatically
- Choose a product with proven performance and longevity
- Ensure the solution was backed by real data, not guesswork
Stuart wasn’t looking for “good enough”. He wanted the best possible solution.
Our Solution
We recommended 3M Prestige 40 Exterior, a premium spectrally selective film engineered to reduce heat without altering the appearance of the glazing.
Stuart immediately understood the logic. “We were simply looking for the best solution for reducing solar gain and UV impact… sometimes it’s just worth paying once than paying many times.”
3M Prestige 40 Exterior offers
- 59% reduction in total solar gain
- Over 90% reduction in infrared radiant heat
- Exceptional clarity with no mirrored appearance
- Longevity with a 3M backed 10-year warranty which is matched with WindowTreat’s workmanship commitment
The Installation
Stuart chose to wait until spring to ensure optimal installation conditions. When the day arrived, the process was smooth and meticulous:
“He cleaned the windows… worked very diligently to make sure the film was installed to the highest standard.”
No contamination, bubbles or visual compromise. Just a flawless finish.
“The experience and the results are great… more than happy to recommend WindowTreat. The process from start to finish has been nothing but fantastic.”
The Result
The improvement was dramatic.
“We’ve noticed a huge difference in the amount of heat that sits within the room.”
Despite several hot days, the temperature stayed far lower than previous years. Stuart estimates:
“My projection would be we’re looking at about a 7 to 9 degree reduction.”
The room now performs exactly as intended:
- Comfortable even in strong sun
- Protected from UV fading
- Clear, natural appearance
- No reflective look
- A subtle red shimmer visible only at certain angles which is proof the infrared rejection is working
“You cannot really see much of a difference… occasionally you see a red glare and that gives you confidence it’s working.”
The Cost
A Space Transformed
Angel’s Asylum is now the year‑round entertaining space Stuart always envisioned. Comfortable, protected, and performing beautifully even in peak sun.
This project shows how spectrally selective window film can solve solar gain problems delivering measurable comfort backed by real‑world data.
Supporting Links
Success Story Window Film Mark – WindowTreat
Best Solar Control Films for Modern Glazing: 3M Prestige Exterior Compared – WindowTreat
Why Internal Solar Control Films Struggle on Modern Double Glazing – WindowTreat
