Which Ceiling Insulation Needs Replacement?


Ceilings Perth insulation lasts for decades, but it needs to be properly maintained. It’s important to check for water damage and mold growth on a regular basis.

Wet insulation is not only uncomfortable, but it can promote mold and mildew throughout the home. Additionally, it loses its R-Value over time.


Fiberglass insulation has enjoyed a long-standing top ranking for home insulation due to its affordability, ease of installation and energy efficiency. This insulating material is also environmentally friendly and comes in several forms: batts, rolls, loose-fill and spray, to meet unique insulation needs and applications.

Generally speaking, fiberglass insulation can last for between 20 and 80 years in most homes without requiring replacement. However, in that time it can lose its effectiveness. One of the main signs that it’s time for a new batch of insulation is the occurrence of a significant increase in your utility bills. This may indicate that old insulation has lost its ability to limit the flow of air and heat, making your home less efficient.

The best way to tell if your existing fiberglass insulation is still up to the task is to check its R-Value. The higher the R-Value, the more effective it will be at limiting the transfer of heat and cold. If you’re not sure what your R-Value is, it’s always a good idea to speak with an experienced and professional insulation company.

While fiberglass is an exceptionally durable insulator, it can become damaged by water. When soaked, it can cause mildew and mold to form, which could damage the wood surrounding it. If this occurs, it’s recommended that you replace the affected insulation immediately, rather than trying to dry it out.

If your fiberglass insulation isn’t soaked through, it should be able to dry out with the help of some fans and direct sunlight. In any case, if your insulation is wet, it’s a good idea to have it replaced with a more resilient and eco-friendly option.

If you’re looking for a more effective insulating option than fiberglass, consider cellulose or spray foam. While cellulose can be more expensive, it’s eco-friendly, fire-resistant and offers superior air blocking capabilities. On the other hand, spray foam is not recommended for homes with finished walls because it can be dangerous to work around and requires specialized equipment and expertise to install correctly.


Cellulose insulation is made from recycled paper that is treated with non-toxic borate compounds to resist fire, insects and mold. It is blown into attics and wall cavities as a dry or wet process. It’s an increasingly popular choice because it can help cut energy costs and is an eco-friendly product.

A cellulose insulation installer will remove the exterior siding around waist height before drilling a row of three-inch holes into each stud cavity and then blow in the cellulose. This method of installation is favored for retrofit insulation because it avoids disturbing the walls and other finishes in the home. It is possible to install cellulose in new construction as well, but it is less common. During the wet-spray installation process, a water hose with a high-pressure spray nozzle (similar to a pressure washer) is attached to the blowing machine. A small amount of moisture is added to the dry cellulose fiber at the nozzle to add natural starches that cause it to stick permanently to the framing materials in the wall cavities.

As its name suggests, cellulose is a chain of sugar molecules. It’s the most abundant natural polymer on Earth and is produced by plants, algae and some bacteria. It is a natural building material that can be found in cotton, wood, and hemp, for example. It’s also found in biofilms, which are communities of bacteria that ooze and glom together on surfaces.

When it comes to insulating homes, cellulose is often used for its R-value, or resistance to thermal flow. It provides an R-value of 3.6 to 3.8 per inch, which is comparable to fiberglass insulation. However, it’s more expensive to install than fiberglass, and the material and labor cost tend to rise as the R-value increases.

In addition, cellulose is heavier than fiberglass and requires more space to install in an attic. It can also be difficult to install properly. An experienced certified attic specialist is needed to ensure the cellulose insulation is densely packed, properly applied and air-tight. Additionally, the cellulose is sensitive to moisture and needs to be protected against condensation.

Rock Wool

Rock wool (or mineral wool) is an environmentally friendly insulator made from actual rocks and minerals. This enables it to block heat and sound in ways that fiberglass cannot. It is available in several forms, including boards that can be inserted between wooden beams in pitched roofs. It is also available in batts and rolls, and in a loose-fill form that can be applied in hard-to-reach spaces.

This insulation has higher R-value per inch than fiberglass, enabling it to prevent energy leakage in attics. It is a great option for re-insulating existing homes and building. It also is a good choice for new construction and commercial buildings that need a high level of thermal insulation. It is also resistant to moisture, which reduces the risk of mildew and mold.

It is made from natural basalt and recycled slag materials, which makes it an eco-friendly product. Rockwool insulation does not contain asbestos, and independent tests have verified that it poses no health risks to the human body if handled properly. However, it is a good idea to wear protective gear during any installation project to ensure that the material does not cause any skin or respiratory irritation.

The thick structure of rock wool also helps it absorb and deflect sound waves, making it a great choice for insulating walls and ceilings in residential and commercial buildings. It can also be used in attics to help improve comfort and safety by reducing noise from outside, as well as keeping the temperature of the home or office more stable.

When insulated correctly, rock wool can save homeowners 50% on heating and cooling costs in certain climates. This translates to substantial savings on utility bills, as well as reduced energy consumption and CO2 emissions. It is also fire resistant and will not rot or mildew, making it an excellent choice for retrofitting older buildings.

Unlike fiberglass batts, spray foam or loose-fill options, rock wool insulation is easy to install in existing buildings. Its rigid board design can be cut and shaped to fit around wall obstructions, ensuring a more seamless installation. Its hydrophobic nature repels moisture, and it is a safe alternative to combustible spray foams that require air sealing, protective equipment, and hazardous off-gassing.

Batt Blanket

A staple in many homes, blanket insulation is available as either batts or rolls. It is made of small fibers—mostly fiberglass but sometimes mineral wool (rock and slag), plastic fibers, and natural fibers like cotton or sheep’s wool. This type of insulation is commonly installed in walls and ceilings to help reduce energy consumption and maintain a comfortable temperature year-round.

When choosing the right type of insulation for your home, consider both the R-value and the density of the insulation. The higher the R-value, the more efficient the insulation is. R-values are calculated by measuring the thickness of the material, while density is determined by the number of air pockets within the insulation.

The most recognizable type of blanket insulation is the pink fiberglass batts that are commonly used in attics and walls. These can provide a high R-value and are often used in cathedral ceilings. If you choose to use these types of blanket insulation, make sure it is without a vapor retarder. This is important because a paper vapor retarder can trap moisture, which can lead to mold and rot.

Another advantage of using blanket insulation is that it can be cut to fit around electrical wires. It is also easier to install than blown-in insulation, which may require the use of special equipment.

One drawback of blanket insulation is that it tends to settle and lose its R-value over time, meaning that it can need to be replaced more frequently than other types of insulation. In addition, it is less effective in colder climates than blown-in insulation.

If you are considering using blanket insulation, it is a good idea to hire a professional for installation and removal services. This is because it will ensure that the job is completed properly and efficiently. Additionally, it will prevent any contaminants from contaminating or damaging the new insulation when it is removed.

When choosing the type of insulation for your home, it is best to consult with a professional to get a better understanding of what R-value will work best in your location and climate. The professional will be able to guide you on the best type of insulation for your home, as well as help you decide on the right R-value for your budget.