We get a lot of customers that call in wondering if they should use single or double bubble insulation. To answer that question, let's take a look at the similarities and differences between the two.Single and double bubble insulation both function in the same way. They both utilize the principles of air space and radiant barrier to stop heat transfer from one surface to another. They are also both equally effective at achieving a 100% Class 1 vapor barrier when properly installed – which by the way, is very easy to do.Both single and double bubble can be installed alone or alongside traditional fiberglass insulation to boost R values. Also, both products come in either a foil/foil or foil/white surface. This can be an important feature to customers if the insulation will be exposed. The white surface of Foil/White Bubble Insulation can make a big difference in brightening up basement walls or metal building interiors.Now for the difference: Just like with traditional fiberglass insulation, the same rule holds true – the greater the airspace, the more effective the insulation is at stopping heat transfer. With two layers of bubbles vs one, as the name implies, double bubble insulation doubles the airspace between the foil layers, resulting in a greater ability to stop heat transfer.Usually the choice between the two simply comes down to space. If you have the space, I always recommend going for the double bubble to get the most bang for your buck.