Is there excess insulation?

As with anything else, too much of a good thing can be a problem. With isolation, too much of a good thing is a problem in some cases, but at other times there is no such thing. I will try to explain when and where you can have too much and where you can have everything you want and more.

I will first try to explain where too much is not good.

To see why too much is not a good thing, we must understand how isolation works. Insulation insulates because it has a large surface-to-space ratio or is soft and fluffy. This makes it difficult for air to penetrate through it and keeps the temperature differences where they are. Soft fluff does not conduct temperature easily.

Now if you take the soft, fluffy material and compress it too much in a small space, it becomes much denser and begins to conduct temperature more easily. The voids needed to curb radiant heat are not there. The product that previously would stop the heat transfer now does not.

What this means is that the R-value or insulation resistance factor is based on having the best possible space to do your job. If you take R-30 insulation and force it into the space that is made for R-19, it will no longer be an R-30 product. In fact, it may not even work as well as an R-19 product.

So be sure to use the right product for the right space you have. Forcing too much in a small space will have a detrimental effect on the product.

Additionally, in an attic situation, you can also cause damage by overfilling it and cutting off the air vents through the eaves or soffit. By stacking the insulation too high on the sides, you can shut off the airflow that will keep the space cooler in the summer and also allow it to breathe so moisture doesn’t build up.

Now, for many situations, more is definitely better. In the walls of a building, you will definitely want to get as much insulation as is practical and can be done without hampering the insulation’s ability to do its job. In attics you will also want to get as much out of it as possible. Attics and roofs are the biggest losers of radiant heat to the outdoors or the area of ​​greatest heat gain for hot climates.

It is always good to have more insulation in an attic or on the roof, as long as it is done in a way that provides adequate ventilation to the space. Also, fiberglass insulation is good as long as it is not compressed and left loose to function properly.

Adding more insulation can be a great thing if you have or are doing it right. Just make sure you’re not trying to overdo it and cause more problems than you’re solving.