Whether or not you need to remove the existing insulation depends on its condition. Removing old insulation is generally recommended if it's damaged, contaminated with mold, or infested with pests.
Removing the old insulation would be more beneficial than leaving it. The older insulation is no longer effective because it has compressed over time. You'll also be able to get a more consistent r-value from the newer insulation because the older insulation is likely variable in height.
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.
Before installing new ceiling insulation in your home you should consider removing any old existing loosefill insulation or insulfluf which might have become contaminated with vermin faeces and urine or just simply have broken down over time.
Signs It's Time to Replace Insulation
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.
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.
The average U.S. homeowner spends about $1,852 to install insulation. Depending on the type of insulation, square footage, site location, and material, you might spend anywhere from $498 to $4,500. Insulation can keep your home cozy and warm on long winter nights or cool and comfortable on hot sunny days.
New insulation can make a huge difference in your utility bills. According to ENERGY STAR: “… homeowners can save an average of 15% on heating and cooling costs (or an average of 11% on total energy costs) by air sealing their homes and adding insulation in attics, floors over crawl spaces and basements.”
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.
You can easily detect areas of missing insulation by walking around your house with a thermal imager and looking for temperature differences. For best results, you'll want at least a 20 degree temperature difference.
Any reputable insulation installer will thoroughly remove old insulation before putting in the new. However, as a homeowner, you should double-check that they remove all of the old insulation as a first step.
The short answer is yes, upgrading insulation can increase the resale value of a home.
Why Fiberglass Batt Is the Best Attic Insulation Material. Fiberglass batt is considered to be the best insulation for attics.
It is possible to over-insulate your house so much that it can't breathe. The whole point of home insulation is to tightly seal your home's interior. But if it becomes too tightly sealed with too many layers of insulation, moisture can get trapped inside those layers. That's when mold starts to grow.
Every type of bulk insulation in common use will block heat equally well whichever way it is installed. EXCEPT… some insulation includes a moisture barrier, and that must be installed right-way round to prevent moisture problems. But the insulation itself works both ways.
Check Behind the Baseboards
Put the wood between the wall and the pry bar to avoid any drywall damage. Then you can easily pry the trim away to get access to the bottom of the wall. If there is existing insulation like fiberglass or cellulose, you will be able to see it in the gap at the bottom of the drywall.
Removing old insulation is generally recommended if it's damaged, contaminated with mold, or infested with pests.
However, there are situations where spray foam insulation is not suitable. For example, you should NOT spray foam insulation over old insulation. Gaps can form when spray foam is applied to batts and rolls, reducing the effectiveness of the new insulation.
Best Time of Year to Buy Insulation
In this case, the spring is the best time, because you will also start to see savings in the summer months. The same is true for warmer climates, just different times of year because you'll want the job finished before the heat sets in.
According to experts from Realtor.com, old homes, especially ones built on or before the 1960s, weren't built with insulation in mind.
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.