Spray Foam Loft Insulation

Spray Foam Loft Insulation

Spray foam loft insulation has become an increasingly popular choice for homeowners and property owners in the UK looking to improve the energy efficiency of their buildings. This comprehensive guide will cover the types of spray foam loft insulation, its benefits, costs, DIY options, and more.
Whether you want to reduce your energy bills, increase your property’s value, or make your living space more comfortable and environmentally friendly, spray foam loft insulation is an option worth considering.
Spray foam loft insulation

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Spray Foam Loft Insulation Types

There are two main types of spray foam loft insulation: open cell and closed cell. Open cell foam is lighter, more flexible, and offers better soundproofing, while closed cell foam is denser, more rigid, and offers better thermal insulation and moisture resistance.

The choice between the two types depends on the specific needs and requirements of your property. In this section, we will further explore the differences between open cell and closed cell spray foam insulation, their respective advantages and disadvantages, and which type might be best suited for your property.

Open Cell Spray Foam Insulation

Open cell spray foam can expand up to 100 times its original size upon application, allowing it to cover hard-to-reach areas that traditional insulation cannot. Due to the air trapped within the cells, the foam has a more ‘spongy’ texture.

Open cell spray foam is recommended for areas of a property with timber frames. This is because the open cell spray foam can expand and contract, allowing the timbers to breathe naturally while still maintaining high levels of airtightness. This prevents drafts and heat loss through gaps in the external envelope.

Some of the key features of open-cell spray foam include:

  • Lower cost compared to closed cell foam
  • Good soundproofing capabilities
  • Expands to fill gaps and voids effectively
  • Allows for some moisture permeability, reducing the risk of condensation buildup
  • Typically lower R-value (thermal resistance) compared to closed cell foam

Closed Cell Spray Foam Insulation

Closed cell spray foam insulation is more rigid than open cell insulation and prevents air or water from penetrating the property’s walls. Due to its high density, closed cell spray foam also provides structural integrity and support to the building.

This type of insulation offers several advantages, such as:

  • Higher R-value (thermal resistance) than open cell foam, providing superior insulation performance
  • Greater resistance to moisture and water intrusion, making it suitable for damp environments or areas prone to flooding
  • Increased structural strength and support for the building
  • More effective at preventing air infiltration
  • Typically higher cost compared to open cell foam

Which Type of Spray Foam is Right for Your Property?

The choice between open cell and closed cell spray foam insulation will depend on various factors, including your property type, specific insulation needs, budget, and local climate conditions.

It’s essential to consult with a professional installer like Spray Foam Tech to determine the best option for your property.

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Spray Foam Loft Insulation Any Good?

Spray foam loft insulation is an excellent choice for many homeowners due to its ability to fill gaps and seal cavities completely, providing up to 50% greater energy savings compared to other insulation products. This helps to improve the overall energy efficiency, comfort, and value of your home or property.

In this section, we will explore the effectiveness of spray foam insulation compared to other insulation materials, as well as its long-term performance and potential drawbacks.

Comparing Spray Foam to Other Insulation Materials

When compared to traditional insulation materials like fibreglass and mineral wool, spray foam insulation offers several advantages. These include:

  • Superior air sealing capabilities, reducing drafts and air infiltration
  • Higher R-values (thermal resistance) per inch of thickness
  • Ability to conform to irregular shapes and hard-to-reach spaces, ensuring complete coverage
  • Reduced risk of mould and moisture-related issues due to its moisture resistance properties

Long-Term Performance and Potential Drawbacks

Spray foam insulation is known for its long-lasting durability, with many manufacturers offering warranties of up to 20 years or more. However, there are some potential drawbacks to consider, including:

  • Higher upfront costs compared to traditional insulation materials
  • Sensitivity to installation quality, requiring skilled professionals for proper application
  • Potential for off-gassing during and shortly after installation, necessitating proper ventilation

Despite these potential drawbacks, spray foam insulation remains a popular and effective choice for many homeowners seeking to improve the energy efficiency of their properties.

Spray Foam Loft Insulation Benefits

There are numerous benefits to using spray foam loft insulation in your home or property. In this section, we’ll discuss some of the most significant advantages that make spray foam a popular choice for insulation:

Improved Energy Efficiency

Spray foam insulation is renowned for its exceptional thermal performance, boasting higher R-values compared to traditional insulation materials. This increased efficiency leads to numerous benefits that directly impact your home and your wallet.

Reduced Energy Consumption: The superior insulating properties of spray foam ensure that your home remains at a consistent temperature throughout the year. By effectively sealing gaps and preventing drafts, spray foam insulation minimizes heat transfer, resulting in less energy required to heat or cool your home.

Lower Utility Bills: As a direct consequence of reduced energy consumption, homeowners can expect to see a decrease in their utility bills. By investing in spray foam insulation, you can save a significant amount on heating and cooling costs in the long run.

Enhanced Indoor Comfort

By effectively sealing gaps and cracks, spray foam insulation significantly reduces drafts and temperature fluctuations, resulting in a more comfortable and consistent indoor environment. This enhanced comfort can be attributed to several factors that contribute to the overall improvement in your home’s atmosphere:

Consistent Temperature Distribution: Spray foam insulation ensures even temperature distribution throughout your home, eliminating hot and cold spots that can cause discomfort. This consistent temperature balance helps create a more enjoyable living space for you and your family.

Reduced Drafts: One of the primary sources of discomfort in a home is drafts, which can be caused by gaps and cracks in walls, windows, and doors. Spray foam insulation effectively fills these gaps, preventing drafts and improving the overall comfort of your home.

Moisture and Mould Resistance

Spray foam insulation offers excellent moisture and mould resistance, which plays a crucial role in maintaining a healthy living environment. The following points illustrate how spray foam insulation combats moisture-related problems and reduces the risk of mould growth:
Superior Moisture Barrier: Spray foam insulation creates a continuous, impermeable barrier that effectively prevents moisture infiltration. This characteristic is especially vital in areas prone to dampness or high humidity, as it safeguards the building structure and interior from potential water damage.
Reduced Condensation: Spray foam insulation minimises the risk of condensation by maintaining consistent indoor temperatures and reducing temperature fluctuations. This helps prevent the formation of condensation on walls, ceilings, and other surfaces, which can lead to mould growth if left unaddressed.
Enhanced Breathability: Open cell spray foam insulation is known for its breathability, allowing moisture to escape from the building envelope while preventing external moisture from entering. This characteristic helps to maintain a balanced humidity level within the home, further reducing the risk of mould growth.
Structural Protection: By providing a moisture-resistant barrier, spray foam insulation protects the building structure from potential damage caused by moisture intrusion. This is particularly important in timber-framed buildings, where moisture can lead to rot and structural weakening.
Healthier Living Environment: By effectively reducing the risk of mould growth, spray foam insulation contributes to a healthier living environment. Mould and mildew can cause various health issues, including allergies, respiratory problems, and even more severe conditions in some cases. Spray foam insulation helps to alleviate these concerns by keeping moisture at bay and preventing the conditions that facilitate mould growth.

Noise Reduction

Spray foam insulation is highly effective in reducing noise transmission, providing a quieter and more peaceful living environment. The soundproofing properties of spray foam insulation can be attributed to the following factors:
Dense Material: Spray foam insulation is made up of dense polyurethane or polyisocyanurate materials, which effectively absorb and dampen sound waves. This characteristic makes it more difficult for sound to pass through the insulated walls, floors, and ceilings, significantly reducing noise transmission between rooms and from external sources.
Gap Sealing: The expansive nature of spray foam insulation ensures that it fills all gaps, cracks, and crevices, creating a continuous sound barrier. This comprehensive coverage eliminates any potential pathways for sound transmission, further enhancing the insulation’s soundproofing properties.
Vibration Dampening: Spray foam insulation also helps to dampen vibrations, which can contribute to noise transmission. By reducing vibrations within the building structure, spray foam insulation minimises the transfer of impact and airborne sounds, resulting in a quieter living environment.
Improved Room Acoustics: The sound-absorbing properties of spray foam insulation can also lead to improved room acoustics. By reducing echoes and reverberations within a room, spray foam insulation contributes to a more comfortable and enjoyable living space, especially for activities such as listening to music or watching movies.
Versatility: Spray foam insulation is suitable for a wide range of applications, including lofts, walls, floors, ceilings, and even around pipes and ductwork. This versatility allows for comprehensive noise reduction throughout the property, ensuring that all areas benefit from the insulation’s soundproofing properties.

Pest Prevention

One often-overlooked benefit of spray foam insulation is its effectiveness in preventing pest infestations. By filling gaps and cracks that could serve as entry points for pests, spray foam insulation can help keep insects and rodents out of your home. This pest prevention is achieved through the following characteristics of spray foam insulation:
Comprehensive Coverage: Spray foam insulation expands to fill even the smallest gaps, cracks, and crevices in your home’s structure. This comprehensive coverage eliminates potential access points for pests, making it more difficult for them to enter your living space.
Durable Material: Spray foam insulation is composed of a strong and durable material that is resistant to damage and deterioration. This durability means that pests, such as rodents, will have a difficult time chewing through or damaging the insulation, further reducing the likelihood of infestations.
Resistance to Moisture: The moisture-resistant properties of spray foam insulation make it less attractive to pests, such as insects and rodents, that are drawn to damp and humid environments. By creating a dry and less hospitable environment, spray foam insulation can help deter pests from nesting within your home’s walls, ceilings, and floors.
Reduced Food Sources: Spray foam insulation’s ability to seal gaps and cracks also helps to prevent the infiltration of organic materials, such as pollen, leaves, and other debris, which can serve as a food source for pests. By eliminating these potential food sources, spray foam insulation can help to discourage pests from settling within your home.

Environmentally Friendly

Spray foam insulation is an excellent choice for homeowners who want to contribute to a greener living environment. By reducing your property’s energy consumption and lowering your carbon footprint, spray foam insulation can have a positive impact on the environment. Here are some ways spray foam insulation contributes to eco-friendly living:
Enhanced Energy Efficiency: Spray foam insulation’s superior thermal performance leads to reduced energy consumption in your home. This means less demand on your heating and cooling systems, resulting in lower greenhouse gas emissions and a decreased carbon footprint.
Reduced Air Leakage: By effectively sealing gaps and cracks in your home’s envelope, spray foam insulation minimises air leakage. This reduces the amount of conditioned air that escapes your home and the unconditioned air that enters it, leading to less energy waste and a more eco-friendly home.
Long-lasting Material: Spray foam insulation has a long lifespan, often lasting as long as the building it’s installed in. This means that, unlike some other insulation materials that may need to be replaced over time, spray foam insulation is a more sustainable choice that reduces waste and the need for additional resources.
Reduced Dependence on Fossil Fuels: By lowering your energy consumption through improved insulation, you can reduce your dependence on fossil fuels. This helps to decrease the overall demand for non-renewable energy sources and contributes to a more sustainable future.


One of the many advantages of spray foam insulation is its long-lasting nature. With a lifespan that typically matches the entire lifetime of your home, spray foam insulation offers homeowners a cost-effective and long-term solution for their insulation needs. Here are some reasons why spray foam insulation is a durable and reliable choice:

Resilient Material: Spray foam insulation is composed of a robust material that can withstand various environmental factors, such as temperature fluctuations, moisture, and pests. Its ability to endure these conditions helps maintain its effectiveness and longevity.
Adhesion: Spray foam insulation adheres strongly to the surfaces it is applied to, ensuring that it remains in place and continues to provide effective insulation throughout its lifespan. This strong bond also helps to prevent sagging, settling, or deterioration, which can compromise the performance of other insulation materials over time.
Resistance to Aging: Spray foam insulation does not degrade or lose its insulating properties as quickly as some other insulation materials. This resistance to aging ensures that it maintains its high R-value and energy-saving capabilities for an extended period.
Minimal Maintenance: Spray foam insulation requires little to no maintenance once it has been installed. This means that, aside from periodic inspections to ensure its integrity, you won’t need to invest additional time or money into maintaining your insulation.
Cost-effective Investment: While the initial cost of spray foam insulation may be higher than some other insulation materials, its longevity and durability make it a cost-effective choice in the long run. By providing consistent and reliable insulation for the entire lifetime of your home, spray foam insulation can save you money on energy bills and prevent the need for costly replacements.
Considering these numerous benefits, it’s clear that spray foam loft insulation is an excellent choice for homeowners looking to improve their property’s comfort, energy efficiency, and overall performance. By investing in this advanced insulation solution, you can enjoy a more comfortable, energy-efficient, and environmentally friendly living space for years to come.

Spray Foam Loft Insulation Cost UK

The cost of spray foam loft insulation in the UK can vary significantly depending on several factors. These factors include the size of the area that requires insulation, the type of spray foam needed (open cell or closed cell), the condition of your building, and your location.
Here’s a closer look at each of these factors and how they can impact the overall cost of your spray foam insulation project:
Size of the area: The larger the area that needs to be insulated, the higher the cost of the project. This is because more materials and labour are required to cover a larger space.
Type of spray foam: Open cell and closed cell spray foam have different costs due to their unique properties and applications. Closed cell foam is generally more expensive than open cell foam, but it offers higher R-values and increased structural support.
Building condition: If your property has pre-existing issues or requires additional work, such as roof repairs, the overall cost of your spray foam insulation project may increase.
Location: The cost of spray foam insulation can vary depending on where you live in the UK, as labour and material costs may differ between regions. Additionally, if your property is located in a remote area, transportation costs may add to the overall project cost.
To provide an accurate estimate for your spray foam loft insulation project, it’s crucial to arrange a pre-installation survey with a qualified installer like Spray Foam Tech.
This assessment will help you determine the specific costs involved in your project and allow you to plan accordingly. By working with a professional installer, you can ensure that your spray foam insulation is correctly installed and delivers the maximum benefits for your property.

Can You Use a DIY Spray Foam Loft Insulation Kit?

While DIY spray foam insulation kits are available on the market, it is generally not recommended for inexperienced users. The proper application of spray foam insulation requires specialized equipment, skills, and knowledge to ensure optimal performance and avoid potential issues.
Hiring a professional installer like Spray Foam Tech will ensure that the insulation is applied correctly and safely, providing the best possible results for your home or property.

Spray Foam Loft Insulation Reviews

Homeowners and property owners who have opted for spray foam loft insulation generally report positive experiences, highlighting the enhanced energy efficiency, increased comfort, and diminished noise transmission that this insulation method provides.
However, the key to reaping these benefits lies in researching and selecting a reputable installer who can guarantee the proper application of the insulation to deliver the expected results.
With a long track record of satisfied customers, Spray Foam Tech is committed to offering top-notch insulation services to the UK market. By choosing an experienced and reliable installer like Spray Foam Tech, you can be confident that your spray foam insulation will be professionally applied, ensuring long-lasting effectiveness and the greatest return on your investment.


Spray foam loft insulation is an outstanding option for homeowners and property owners in the UK seeking to enhance their building’s energy efficiency and comfort. Boasting superior thermal performance, moisture resistance, and air-sealing capabilities, spray foam insulation can offer substantial benefits when installed properly.
By collaborating with a professional installer like Spray Foam Tech and thoroughly evaluating the unique requirements of your property, you can guarantee that you fully capitalise on this versatile and efficient insulation solution.
In addition to improving energy efficiency, spray foam loft insulation also contributes to a more comfortable indoor environment, reduces noise transmission, and prevents pest intrusion. Moreover, it has a long lifespan, making it a cost-effective, long-term investment.
It is important to remember that choosing a reputable and experienced installer is crucial for ensuring the safe and effective application of the insulation, ultimately maximizing its benefits.
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