Ever since he was a little kid, Gizmo Guy always has loved snooping around buildings under construction.

So he jumped at the chance to check out the shiny new Saint-Gobain North American corporate headquarters in Malvern, where he was promised insights into its high-tech building materials - the spécialité de la maison.

And he learned that . . .

People in tightly sealed glass-walled buildings don't have to throw stones (or put A.C. into high gear) to get comfortable on a hot day.

Or shout to be heard, even in a wide-open floor plan.

Or fear for their health in said sealed environment.

Heavy with products made worldwide by Saint-Gobain and its North American construction-materials subsidiary CertainTeed Corp., the new headquarters at the 320,000-square-foot campus are a "living laboratory," CEO John Crowe said, designed "to demonstrate the power our products have to improve the quality of people's lives." (Alas, the 800-plus employees won't be getting a "guinea pig" bonus.)

Like that modernistic exhibit of edgy building shells that Saint-Gobain put up on the Ben Franklin Parkway last summer, the timing of the Malvern opening is symbolic, Crowe said, cued by the firm's 350th anniversary.

Clearly, the firm has come a long way from King Louis XIV - the fab dresser and amateur architect who kick-started the enterprise (originally anointed La Manufacture royale de glaces) to snazz up his Palace of Versailles with a shiny Hall of Mirrors.

Saint-Gobain didn't invent the process of coating heavy glass with reflective layers of tin and mercury. But the French concern did come up with a novel alternative to blown-glass mirrors, instead pouring the molten material onto a metal table mold. That enabled the first "big screen" mirrors - much to the entertainment of 17th- and 18th-century "selfie" posers.

High-tech glass is still a big deal at the new Saint-Gobain building, a onetime insurance company domain "stripped down to the steel, then entirely rebuilt," Crowe said.

In a conference room, we took in a rendering of that magically charged privacy glass ("polymer dispersed liquid crystal-infused"), which shifts from see-through to opaque at the push of a button.

Even more dramatic is the 17,000 square feet of electronically tintable ("electrochromic") SageGlass on the western and southern elevations of the façade. Triggered by the plant operations computer, light-reactive sensors, a wall switch or even a cellphone, voltage is applied to five ceramic layers (collectively 1/50 the thickness of a strand of hair) embedded inside the glass, which then turn it different shades of gray. Not 50, though it is possible to tame a piece of glass to reveal three differently tinted bands within a single pane.

"On a hot day with sun overhead, you might have the glass appear darkest at the top, medium gray in the middle and lightest at the bottom. That would absorb and re-radiate the midday heat and cut the glare at the top, while still allowing people to enjoy the light and outside views," SageGlass CEO Alan McLenaghan said. It can tune out as much as "91 percent of the heat while allowing in 99 percent of the light."

A retrofitable product that "pays for itself," SageGlass made "all the difference" in attracting room rentals after being installed in the glass ceiling of the Hamilton Garden above the Kimmel Center's Perelman Theater, said Saint-Gobain building scientist Lucas Hamilton.

"It was a space previously too hot to hold weddings and other receptions on a sunny day," Hamilton said. "Now it's very popular. Grooms especially like to go in and play with the controls, to dial in the right lighting 'tone' for the happening."

What didn't catch our attention at Saint-Gobain was just as important as what did - especially in a reception zone below vertically hung Ecophon Focus Ds tiles. Made mostly of recycled spun glass with a plant-based binder (ergo the "Eco"), these wavy panels aren't just pretty. They also absorb sound and diffuse glare from overhead strips of LED lights. "This material can really make the difference in an open floor plan like ours or a classroom where different groups are huddled in different areas," Crowe said. "You can talk at normal levels."

The right building materials can even take a stab - literally - at airborne microbes that want to plant themselves on walls to fester as fungus and black mold.

"To live, microbes need food - starch or sugar - and need water," Hamilton said. "But, like a stool, if you knock out one leg, the bad thing [microbe] falls over." So Saint-Gobain Adfors wall coverings (sub-branded Novelio) pack synthetic derivative silver ions "that make the food un-nutritious," he said. And, during manufacturing, Saint-Gobain roughs up the texture of its gypsum wallboard and drywall tapes with a "needle structure" that "scratches the shells of the mold spores so the stuff dries up and dies."

Sounds like the happy ending to a scary movie.