Age 👴🏼 – Insulation is typically pretty hearty. For most homes, it can last for 20-80 years! That being said, like all things, insulation tends to wear down over time. If you are living in an older home and encountering some of the following problems, it may be time for a replacement.
If the fiberglass insulation is of good quality, installed correctly, and not disturbed, you can expect it to have the same lifetime as the building itself — usually 60+ years.
Insulation, depending on the material used, can last for decades if properly cared for. Some insulation materials are composed of natural materials and will eventually degrade. Others are made from synthetic material and can last for nearly a century before needing replacement.
Blown fiberglass insulation scores an R-value of 3.2 to 3.8, making it slightly less likely than rolled fiberglass to prevent the flow of heat into and out of your house. That being said, though, blown fiberglass insulation isn't meant to cover huge areas like rolled fiberglass insulation.
However, insulation can start falling from fiberglass batts after 15 to 20 years, so if your insulation was installed in batts well over a decade ago, it might be time for an inspection or a home energy audit.
Insulation lasts much longer than you would think. According to the International Association of Certified Home Inspectors, house wrap, spray foam, and wrap tape can last upwards of 80 years or more. Cellulose, foam board, white loose-fill, rock wool, fiberglass, and loose fill can all last more than 100 years.
Why Fiberglass Batt Is the Best Attic Insulation Material. Fiberglass batt is considered to be the best insulation for attics.
In most homes, loose-fill insulation can survive anywhere from 80 to 100 years before needing replacement, provided that it is not damaged.
In general, either batt or rolled insulation or blown loose-fill insulation (fiberglass or cellulose) can be installed on top of old insulation. If you need to add new insulation on top of old insulation please note the following: Draftproofing should be completed prior to the addition of more insulation.
Removing old insulation is generally recommended if it's damaged, contaminated with mold, or infested with pests. However, if the insulation is in decent shape and just needs a boost, adding a new layer on top can be a cost-effective option.
Wet insulation in a wall will migrate to the bottom soaking the wallboard and framing materials. Wetness (existing even just for a few days) will not only reduce the insulating quality of the insulation, but it might not dry soon enough to prevent mold and wood decay from forming.
The International Association of Certified Home Inspectors states that spray foam insulation, wrap tape and housewrap insulation can last for more than 80 years. At the same time, cellulose, loose-fill, foamboard, loose fill and rock wool insulation can last up to 100 years.
You'll spend anywhere from $1 to $3 per square foot for batt or roll insulation, including materials and labor.
Attic insulation costs anywhere from $1,680 to $3,125, depending on the size of your attic and the material used. On average, most homeowners shell out around $2,380. These costs include the insulation materials and installation by a professional.
The advantages of blown insulation are clear: from its efficient installation and eco-friendly materials to its pest control and fire resistance properties. If you're considering upgrading your home's insulation, blown insulation offers numerous benefits that make it a superior choice.
R15 insulation offers slightly better thermal insulative properties than R13. Some of its formats are a fraction of an inch thicker than R13, making it more effective at helping with energy efficiency.
The fiberglass used in batts, rolls, and blown-in insulation is an inert material. As such, it doesn't break down or “go bad” on its own. However, this does not mean the material is indestructible.
You can choose from different materials like cellulose (made from recycled paper), fiberglass, or mineral wool. Cellulose is an eco-friendly and cost-effective insulation for attics. Fiberglass and mineral wool are also popular choices because they are good at keeping heat in or out and resist moisture and pests.
The higher the R-Value, the better the thermal performance of the insulation. The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.
Fiberglass batt insulation does have some drawbacks. They can be itchy and irritating to handle, and inhaling the fibers can cause respiratory problems. It's important to wear protective clothing and a mask when handling and installing fiberglass batts.
Unfortunately, the majority of homes built 50 years ago were not insulated at all. It is important to be aware of these insulation issues if your home is 50+ years old. Replacement (or new installation) may be necessary if your home is drafty, if you have high utility bills, etc.
A home requires air circulation, so if it is too tightly sealed and over-insulated, moisture can build up that causes mold. With too many layers of insulation, mold can even grow in between the layers. Mold in the home can cause allergy flare-ups, allergic reactions, and breathing issues.
The recommended R-value for attic insulation can vary depending on the climate zone in which you live. The U.S. Department of Energy recommends attic insulation levels of R-49 to R-60 for most homes in colder climates, and R-30 to R-49 for homes in warmer climates.