What You Need To Know About Insulation Life Expectancy

There may be no region in the U.S. where insulation is as important as it is in the Midwest. From scorching summer heat to bitter Arctic wind chills, your home must withstand a lot of extremes. At Midwest Roofing Siding & Windows, we understand a well-insulated home can keep you and your family safe and comfy year-round. 

We also know insulation lasts a long time, but not forever. The insulation we use today is far more advanced than insulation being put into houses as little as 10 or 15 years ago. Chances are, if you live in an older home, the insulation in your attic isn’t the best it can be. 

Signs You Need New Insulation 

There are a few ways to know if your attic is well insulated enough. One of the easiest is to head up there and take a look around. If you have loose-fill insulation, it should be at a level above the floor joists. If it’s higher, you can measure its depth with a yardstick to estimate its R-Value. Fiberglass and cellulose insulation gives you about R-3 per inch. Ideally, you should be above R-40 for an attic in the Midwest.

Your house will also let you know if it needs more insulation. You may have trouble keeping your home warm in the winter because too much heat escapes through the attic. In severe cases, ice dams can form, potentially causing severe damage. 

Types of Insulation

The type of insulation you have in your attic also comes into play when determining if you need more. The types of insulation batts, blankets, and loose-fill which were used decades ago are nowhere near as efficient as today’s insulation. Some truly old homes from the 1800s were insulated with anything from newspaper to seaweed. These days, we have better options:

  • Blankets, batts, and rolls are typically made of fiberglass or rock wool, and are ideal for fitting between wall and ceiling joists. Although not always the most efficient, these types of insulation are popular because DIY installation is relatively easy. 
  • Sprayed and foam-in-place insulation is usually applied from a handheld canister to insulate small spaces and cracks, but can also be sprayed into larger spaces by a professional with special equipment. At may be made of several different chemical compounds, and is good for filling wall cavities and unfinished attic and crawlspaces.
  • Loose-fill and blown-in insulation are most often made of cellulose, fiberglass, or mineral wool. It is ideal for attics because it can conform to any unusually-shaped space, and is blown in using specialized equipment. It’s also the perfect insulation to add over the top of existing insulation. 

Adding vs. Replacing Attic Insulation 

If your attic isn’t as well insulated as it ought to be, you have two options. You can have all the old insulation ripped out and replaced or you can add new insulation on top of your old insulation. Choosing which path to take depends on a few factors. 

Most important is the condition of your old insulation. If it’s still in relatively good shape, it’s usually best to simply add new insulation on top of it. It’s when the old insulation is wet, rotted or infested that you really should have it completely removed before putting new insulation in. 

How Long Insulation Lasts

Different types of insulations have different life expectancies, so you may be able to estimate how long yours will last if you know when it was installed. Fiberglass insulation can potentially last 80 to 100 years if it is undamaged, but bits can start to fall from fiberglass batts after 15 or 20 years. If shouldn’t need to be replaced after such a short time, but it’s worth an inspection. 

Cellulose insulation usually lasts 20 to 30 years before it starts to degrade, and mineral wool also lasts decades as long as it is not damaged. Spray foam insulation is one of the longest-lasting. Many homeowners never have to replace it in their lifetime. 

Learn More About Attic Insulation

It can be hard to figure out whether or not your attic is as well insulated as it should be. When in doubt consult a professional. Our team at Midwest Roofing Siding & Windows has many years of experience insulating homes in Minneapolis and Saint Paul, and we’d be happy to offer a consultation to make sure your insulation is in good shape. 

At Midwest Roofing Siding & Windows, we understand the importance of living in a well-insulated home. Contact us today to learn more about how we can help make your home more comfortable and energy-efficient in the Twin Cities area.

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