Double bubble insulation does work on metal buildings, but only in a narrow way. It needs an open air gap next to its foil face, and its main jobs are blocking summer sun heat and stopping condensation from dripping off the steel. Pressed flat against metal with no air space, it adds very little R-value. For a shop or barn you want warm in winter, it usually needs to be paired with real insulation like spray foam or fiberglass.
Double bubble is the shiny roll of foil with two layers of plastic bubbles in the middle. It’s cheap and easy to staple up, which is why so many pole barns and steel garages around Denver have it. Our Grizzly Insulation Co crews get called to a lot of them in January, so here’s what it really does.
How Does Double Bubble Insulation Work?
It reflects radiant heat. The foil bounces back heat that travels as invisible infrared light, like the heat you feel from a sunny metal roof. The bubbles add a thin layer of trapped air, but they’re only about a quarter inch thick.
Most of its rated performance comes from the air space in front of the foil, not from the bubbles. Our blog on what R-value means explains why trapped air matters so much.
Does Double Bubble Insulation Need an Air Gap?
Yes, and that part is settled. Virginia Tech’s extension guide to radiant barriers and reflective insulation says reflective insulation must have an air space next to its shiny side. Without one, the foil just passes heat straight through. The same guide notes it works best against downward heat, like summer sun on a roof.
On a metal building, that means installing it on furring strips or purlins with a gap, not stapled tight against the steel. If you already see damp marks inside, our page on wet-looking spots on walls explains the usual causes.
Does Double Bubble Work in a Cold Denver Winter?
Not by itself. In winter, most heat leaves a building by moving through materials and leaking with air, not by radiating. A thin foil layer can’t slow that much. A heated shop in Denver needs real R-value to stay warm.
You’ll see packaging that promises huge R-values from a quarter-inch roll. Those numbers usually assume a perfect still-air gap on both sides in a lab. Nobody has shown a thin foil roll matching inches of foam or fiberglass on a real winter wall.
What Is Double Bubble Good for on Metal Buildings?
Stopping condensation drips. Warm, damp air hitting cold steel turns into water that rains down inside. A sealed foil layer keeps that air off the metal.
Cutting summer heat. On a sunny roof, the foil reflects a lot of radiant heat back out.
For an unheated barn or equipment shed, those two benefits may be all you need. Our blog on condensation spots on walls explains how warm air meets a cold surface.
Is Double Bubble Better Than Single Bubble Insulation?
A little, but not by as much as the packaging suggests. Double bubble has two layers of bubbles instead of one, so it’s slightly thicker and a touch sturdier. The foil faces do most of the work either way, and both need the same air gap.
For condensation control, either one works if the seams are taped. If you’re paying more for a double bubble expecting real winter warmth, that money is usually better spent on foam. Our blog on whether closed cell foam absorbs water explains why foam handles moisture so well.
Faced fiberglass blankets made for metal buildings are the budget option. They need a well-sealed facing to keep moisture off the steel.
Can You Combine Double Bubble With Other Insulation?
Yes, as long as the foil faces an air gap. Some builders install fiberglass or foam board first, then a reflective layer facing a gap. That pairs real R-value with the radiant and moisture benefits.
If your shop were ours, we’d skip double bubble on a heated building and spray closed cell foam on the walls and roof instead. It does the condensation job and the insulation job in one pass. For a cold storage barn, a properly gapped reflective layer is a fair, low-cost choice. Our commercial insulation team works on shops, warehouses and pole barns of every size.
Is Double Bubble Worth It for a Metal Garage in Denver?
For an unheated garage, it can be. It stops drips and keeps summer heat down. If you plan to heat the space or use it as a workshop through Denver winters, you’ll want more. Our guide to insulating a garage covers the options.
Use Double Bubble Insulation Where It Actually Works
Double bubble insulation works on metal buildings when it faces an air gap, and it shines at blocking summer heat and drips. For a heated building, pair it with real insulation or go straight to spray foam.
Need a metal building that stays dry and warm in Denver? Grizzly Insulation Co can help. We’re BPI Certified and an Xcel Energy rebate partner.
Does Double Bubble Insulation Really Work on Metal Buildings
Double bubble insulation does work on metal buildings, but only in a narrow way. It needs an open air gap next to its foil face, and its main jobs are blocking summer sun heat and stopping condensation from dripping off the steel. Pressed flat against metal with no air space, it adds very little R-value. For a shop or barn you want warm in winter, it usually needs to be paired with real insulation like spray foam or fiberglass.
Double bubble is the shiny roll of foil with two layers of plastic bubbles in the middle. It’s cheap and easy to staple up, which is why so many pole barns and steel garages around Denver have it. Our Grizzly Insulation Co crews get called to a lot of them in January, so here’s what it really does.
How Does Double Bubble Insulation Work?
It reflects radiant heat. The foil bounces back heat that travels as invisible infrared light, like the heat you feel from a sunny metal roof. The bubbles add a thin layer of trapped air, but they’re only about a quarter inch thick.
Most of its rated performance comes from the air space in front of the foil, not from the bubbles. Our blog on what R-value means explains why trapped air matters so much.
Does Double Bubble Insulation Need an Air Gap?
Yes, and that part is settled. Virginia Tech’s extension guide to radiant barriers and reflective insulation says reflective insulation must have an air space next to its shiny side. Without one, the foil just passes heat straight through. The same guide notes it works best against downward heat, like summer sun on a roof.
On a metal building, that means installing it on furring strips or purlins with a gap, not stapled tight against the steel. If you already see damp marks inside, our page on wet-looking spots on walls explains the usual causes.
Does Double Bubble Work in a Cold Denver Winter?
Not by itself. In winter, most heat leaves a building by moving through materials and leaking with air, not by radiating. A thin foil layer can’t slow that much. A heated shop in Denver needs real R-value to stay warm.
You’ll see packaging that promises huge R-values from a quarter-inch roll. Those numbers usually assume a perfect still-air gap on both sides in a lab. Nobody has shown a thin foil roll matching inches of foam or fiberglass on a real winter wall.
What Is Double Bubble Good for on Metal Buildings?
For an unheated barn or equipment shed, those two benefits may be all you need. Our blog on condensation spots on walls explains how warm air meets a cold surface.
Is Double Bubble Better Than Single Bubble Insulation?
A little, but not by as much as the packaging suggests. Double bubble has two layers of bubbles instead of one, so it’s slightly thicker and a touch sturdier. The foil faces do most of the work either way, and both need the same air gap.
For condensation control, either one works if the seams are taped. If you’re paying more for a double bubble expecting real winter warmth, that money is usually better spent on foam. Our blog on whether closed cell foam absorbs water explains why foam handles moisture so well.
What Insulation Works Better on Metal Buildings?
If you heat the space, spray foam is the top choice. Closed cell foam sticks to steel, seals every seam and adds strength. See what closed cell spray foam is and its R-value per inch.
Faced fiberglass blankets made for metal buildings are the budget option. They need a well-sealed facing to keep moisture off the steel.
Can You Combine Double Bubble With Other Insulation?
Yes, as long as the foil faces an air gap. Some builders install fiberglass or foam board first, then a reflective layer facing a gap. That pairs real R-value with the radiant and moisture benefits.
If your shop were ours, we’d skip double bubble on a heated building and spray closed cell foam on the walls and roof instead. It does the condensation job and the insulation job in one pass. For a cold storage barn, a properly gapped reflective layer is a fair, low-cost choice. Our commercial insulation team works on shops, warehouses and pole barns of every size.
Is Double Bubble Worth It for a Metal Garage in Denver?
For an unheated garage, it can be. It stops drips and keeps summer heat down. If you plan to heat the space or use it as a workshop through Denver winters, you’ll want more. Our guide to insulating a garage covers the options.
Use Double Bubble Insulation Where It Actually Works
Double bubble insulation works on metal buildings when it faces an air gap, and it shines at blocking summer heat and drips. For a heated building, pair it with real insulation or go straight to spray foam.
Need a metal building that stays dry and warm in Denver? Grizzly Insulation Co can help. We’re BPI Certified and an Xcel Energy rebate partner.
Call (303) 854-6221, or check out our spray foam insulation services.
Frequently Asked Questions
It depends almost entirely on the air gap in front of the foil. Pressed flat, it’s very low.
It can, when it’s sealed and keeps damp air off the steel.
It can, but you lose most of its benefit. Leave an air gap.
No. Spray foam insulates and seals far better, especially in winter.
Only with an air gap, and it adds little in a heated building. See the highest R-value insulation for better wall options.