You never want to use faced fiber glass when you are adding another layer to existing attic insulation. What you should use in this situation is unfaced fiber glass that does not have any vapor retarder. When you learn how to lay attic insulation, you’ll realize that the insulation facing acts like a vapor retarder and will help to lower the level of moisture that enters through a wall or any other surface. If you added a second vapor retarder over layers of faced insulation, any amount of moisture, no matter how small, that gets through the first layer will actually condense onto the second. Some damage to ceilings or walls will occur because of this condensation and the areas will be stained. If the condensation continues for a long period of time, then there may even be structural damage.

Any decent guide that tells you how to lay attic insulation should always cover the subject of radiant barriers. There are three main types of radiant barriers. Single layer film material, bubble film or multilayer, and then single films that are put directly on the underside of the sheathings on the roof, are the three most common types. However, you must know that radiant barriers are not actually insulation. In fact, they do not even have an r-value. The fact is that you can find radiant barrier products which actually use the concept of trapped air and that enables them to have an r-value, even though it will be very small.

Another interesting fact when learning how to lay attic insulation, is the difference between summer r-value and winter r-value. Summer r-value is actually the insulation rating when examining the heat flow in a downward direction. Winter r-value is when you examine the heat flowing upwards. Even though radiant barriers are sometimes used, it is almost always more cost effective and overall effective to simply use quality insulation products. Also, in truth, the actual heat flow which is resisted by radiant barriers is usually much less than what the manufacturers claim. Learning how to lay attic insulation is a skill that anyone can pick up as long as they learn the right methods that are safe and effective.

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1. Attic Radiant Barrier – Cut Heating and Cooling Bills

Although basic common sense would seem to dictate that the thicker an insulation product, the better it will be at the job of insulating a home. Unfortunately, this is a case where common sense is incorrect. Insulation with a higher r-value doesn’t necessarily mean that it is thicker than products with lower r-values. In fact, it’s probably thinner than lower-rated insulation products. Actually, if two products are different in thickness, if they have identical r-value ratings, then they will probably be equally good at resisting heat. The facts of insulation r-value is sometimes completely against common sense.

Unfortunately, not all facts of insulation r-value products are necessarily positive. The way that testing is done on insulation in order to determine its r-value is by testing the product in an environment with a stable temperature of 70 degrees Fahrenheit, where there is no air movement at all. Obviously, we use insulation in rooms and homes where the problem is that we have too much air movement and temperature isn’t always an ideal 70 degrees. Sometimes the insulation’s r-value isn’t always a truly accurate indicator of how well it resists heat flow.

In North America, the standard insulation rating of R-12 is the recommended level (this can vary though from state to state). There are many interesting facts of insulation r-value and how they are created and used. It may seem obvious, but the r-value of certain types of housing insulation is dramatically lowered if there are air or water leaks. Here’s one of the interesting facts of insulation r-value: Insulation one inch thick is actually the equivalent of having 30 inches of concrete. That’s how effective true insulation products are at resisting heat flow.

However, there are three main types of insulation and each one is made from a different material. House insulation r-value in blown-in-cellulose is actually 3.70 per inch. Another material widely used for insulation is fiberglass and it has a rating at 3.14 per inch. Finally, one of the best materials is expanded polystyrene which is at 4.00 per inch.

The goal is to protect your home and keep the air inside stable and comfortable no matter what the weather outside is like. Learning the facts about insulation r-value will help you when deciding what type of insulation you want to have installed into your home. It may cost you more money up front to buy better insulation, but you’ll definitely save money in the long run when you realize that the insulation is doing its job. In the end, learning the facts about r-value will help you save a lot of money.