How Long Does Loft Insulation Last?
This is part of our complete guide to roof and loft insulation.
Loft insulation plays a vital role in regulating indoor temperatures, reducing heating and cooling costs, and creating a comfortable living environment. Properly installed loft insulation acts as a thermal barrier, preventing heat loss during cold winters and keeping your home cooler in the scorching summer months. Over time, however, the effectiveness of loft insulation can diminish, prompting homeowners to ponder how long their insulation can last. Understanding the factors that influence the lifespan of loft insulation can help homeowners determine when it might need replacement or maintenance.
Insulation can last as long as 40 years or as few as five, depending on whether it is properly maintained. Many factors can play into the lifespan of loft insulation, such as the type of insulation, climate conditions, installation quality, mould and moisture exposure, and pest or rodent accessibility.
When Should I Replace my Loft Insulation?
Here are some signs that it may be time to replace your loft insulation:
Your energy bills have been increasing. If you have noticed a significant increase in your energy bills, this could be a sign that your loft insulation is not performing as well as it used to.
Your home is not as warm in the winter or as cool in the summer as it used to be. This is another indication that your loft insulation may need to be replaced.
You see visible signs of damage to your insulation, such as water damage, mould growth, or pests. If you see any of these signs, it is important to have your insulation inspected and replaced immediately.
If your home is old, it may have less insulation than newer homes.
If you are unsure whether your loft insulation needs to be replaced, you can always have a professional inspection done. A qualified inspector will be able to assess the condition of your insulation and make recommendations for replacement if necessary.
How Long Does Fibreglass Insulation Last?
Fibreglass insulation can last for a very long time, typically between 80 and 100 years. This is because fibreglass is a very durable material that is not susceptible to degradation from pests, moisture, or UV rays. However, the actual lifespan of fibreglass insulation can vary depending on several factors, including:
The quality of the insulation: Higher-quality fibreglass insulation will typically last longer than lower-quality insulation.
The quality of installation: Properly installed fibreglass insulation will last longer than fibreglass insulation that has been installed incorrectly.
The environment: Fibreglass insulation that is exposed to moisture or extreme temperatures may not last as long as fibreglass insulation that is kept dry and at a stable temperature.
In general, you can expect fibreglass insulation to last for many years without needing to be replaced. However, it is always a good idea to have your insulation inspected periodically to ensure that it is still in good condition.
How Long Does Blown-In Insulation Last?
The longevity of blown-in insulation depends on the type of insulation material used, the quality of installation, local climate conditions, and the level of maintenance it receives. Let's explore these factors to provide a better understanding of how long blown-in insulation typically lasts:
Type of Insulation Material:
Fibreglass Blown-In Insulation: Fibreglass blown-in insulation is known for its durability. When properly installed, it can last for several decades, often in the range of 20 to 30 years or even longer.
Cellulose Blown-In Insulation: Cellulose blown-in insulation, which is made from recycled paper products and treated with fire retardants, may have a slightly shorter lifespan, typically ranging from 10 to 25 years. This shorter lifespan is due to factors like settling and potential moisture issues.
How Long Does Spray Insulation Last?
Like blown-in insulation, the first variable in the lifespan of spray insulation will be what type of spray foam was used in your loft.
Types of Spray Foam:
Open-Cell Spray Foam: Open-cell spray foam insulation is typically less dense and has a lower R-value compared to closed-cell foam. While it's less expensive, its lifespan is generally shorter, ranging from 20 to 30 years. Open-cell foam is more susceptible to moisture absorption and may require more frequent maintenance to address moisture-related issues.
Closed-Cell Spray Foam: Closed-cell spray foam is denser and has a higher R-value, making it more durable and resistant to moisture. When properly installed, it can last for several decades, often exceeding 30 years. Closed-cell foam's resistance to moisture and its superior insulation properties contribute to its longer lifespan.
Variables of Loft Insulation Lifespan
All forms of loft insulation are susceptible to a variety of different elements that can negatively impact their longevity. Some of these issues include:
Quality of Installation: Proper installation ensures that the insulation material is evenly distributed, without gaps or compression. When insulation is installed correctly, it is more likely to maintain its effectiveness over time. Poorly installed insulation can lead to reduced efficiency and a shorter lifespan.
Local Climate Conditions: Extreme conditions can lead to insulation material degrading more quickly. Additionally, insulation in regions with frequent freezing and thawing cycles may be subjected to more stress, potentially reducing its lifespan.
Maintenance and Upkeep: Regular maintenance is crucial for preserving the efficiency and lifespan of blown-in insulation. Inspections to check for issues like settling, moisture, or pest infestations are essential. In cases where insulation settles over time, topping up or adding more insulation may be necessary to restore its effectiveness.
Pest Control: Pests and rodents can pose a significant threat to blown-in insulation. They may nest in or damage the insulation material, leading to a reduction in effectiveness. Regular pest control measures and sealing potential entry points can help protect your insulation and extend its life.
Settling and Compression: Over time, insulation may settle and compress, which can reduce its thermal performance. Settling can create voids within the insulation, allowing heat transfer. To address this, periodic inspections and topping up the insulation are recommended.
Moisture Control: Moisture infiltration can damage insulation and create conditions for mould growth. Proper moisture control measures, such as adequate roof and attic ventilation, are crucial for preventing moisture-related damage and ensuring the insulation lasts longer.
Trust the Professionals
Regular inspections, maintenance and proactive measures to address issues such as moisture, pests can extend the life of your insulation. If you're unsure about how to get started with insulation, you can always consult with professionals who specialise in insulation and can assess your specific situation, offering guidance and recommendations based on your unique needs.
If you have questions or concerns about insulation for your home, drop us a note or give us a call at +44 141 951 7887. With over 30 years’ combined experience in the energy efficiency industry and multiple awards, MPC Energy Ltd are known as one of the UK’s most trusted installers of home energy efficiency improvements.
