Ask virtually anyone about insulating a wall and there is a good chance, depending on the person’s knowledge level, that the first thing out of his or her mouth will be either insulation or Green Glue. While it is almost unfair to compare two products designed for completely different purposes, since they are both linked so strongly to soundproofing it may be helpful to look at each to compare the relative merits.
How Does Insulation Block Sound?
Since soundproofing is simply a side effect, it is important to first understand how insulation performs its primary task – prevent heat transfer. Among commonly found materials, air is one of the poorest conductors of heat. A barrier of simple air can greatly reduce the amount of heat that passes through something.
The purpose of insulation is to create this air barrier, thus preventing heat transfer. With its fluffy texture composed of tiny fibers, insulation is designed to trap air in pockets among the fibers. As a lucky side effect, this fluffy, fibrous material also forms a pretty good sound baffle when compared to most building materials. As sound hits it, the sound waves are absorbed, reflected and deflected, with less sound energy getting through to the other side.
How Does Green Glue Block Sound
As a product designed specifically for the purpose, Green Glue is far more effective when it comes to soundproofing than general insulation. The chemical composition of Green Glue was formulated to create a revolutionary phenomenon when sound waves pass through it. When sound hits a layer of Green Glue, some will bounce off and some will pass through. As it passes through, this special chemical composition literally changes the sound energy to heat energy. Instead of noise coming out the other side, a tiny bit of heat comes out instead.
Looking at these facts, most people will wonder, if Green Glue is such an effective sound blocker, why do so many people mention insulation when talking about soundproofing? There are two answers and the first is knowledge – many people are simply unaware of the sound to heat process and think of Green Glue as a sealant like any other. The second reason is technological limits. Until very recently, insulation was one of the best low cost solutions.
The bottom line is this: If a person is trying to prevent heat from passing through a wall, insulation is a great way of doing so. If that person is trying to prevent sound from passing through, Green Glue is a far superior choice.