Polyisocyanurate (PIR) insulation represents a significant advancement in insulation technology, boasting remarkable thermal efficiency.
This guide explores the world of PIR insulation, including its production process, applications, and comparative performance against other insulation types. Aimed at both homeowners and construction professionals, the content is structured to provide a deep understanding of PIR insulation.
This knowledge is crucial for making informed decisions on insulation choices, guiding towards energy-efficient and cost-effective construction methodologies.
Contents
- What is PIR Insulation?
- Why is PIR Insulation so expensive?
- What are the pros and cons of PIR Insulation?
- UK PIR Insulation comparison chart
- Comparing PIR to Other Insulation Board Types
- Is PIR Insulation right for me?
- FAQ’s
What is PIR Insulation?
Polyisocyanurate (PIR) insulation, a type of foam board, is well known for its superior thermal insulation capabilities. The production of PIR involves a chemical reaction between a polyol and an isocyanate, creating a rigid foam. This foam stands out for its high thermal resistance, low water absorption, and impressive structural strength. The distinctive fine cell structure and closed-cell composition of PIR contribute to its exceptional thermal performance and resistance to moisture.
Why is PIR Insulation so Expensive?
PIR insulation's notable performance comes with a higher price tag compared to alternatives. Several factors contribute to this cost disparity:
- Manufacturing Complexity: The production of PIR is more complex and requires more energy than that of other insulations, demanding precise conditions and sophisticated technology.
- Material Efficiency: PIR's higher thermal efficiency per thickness means less material is needed for equivalent insulation. However, this efficiency comes at a cost, influenced by the manufacturing complexities and material properties.
- Fire Resistance and Durability: PIR generally exhibits better fire resistance and moisture resistance than other foam insulations, enhancing its durability and impacting its cost.
- Market Dynamics: With stringent building codes and a push for energy efficiency, the demand for high-performance insulation like PIR is growing. However, supply chain issues and raw material availability can affect pricing.
- Environmental Regulations: Compliance with environmental standards, particularly regarding chemical use in manufacturing, can increase production costs.
- Logistics: PIR's rigidity necessitates careful handling and transportation, further adding to its cost.
Despite its higher initial expense, PIR insulation's benefits - superior thermal performance, durability, and fire resistance - justify its cost, offering long-term savings and performance advantages.
What are the Pros and Cons of PIR Insulation?
Pros of PIR Insulation:- High Thermal Efficiency: PIR provides exceptional thermal resistance in a compact form, ideal for space-constrained applications.
- Fire Resistance: It offers improved fire safety over many other foam insulations.
- Moisture Resistance: Its resistance to water absorption minimizes the risk of mould and water damage.
- Durability: PIR's stable performance over time translates to lasting benefits and reduced need for replacement.
- Ease to Handle: Typically supplied in board form, PIR is lightweight and easy to tailor, simplifying the installation process.
- Cost: It's more expensive upfront than alternatives like fiberglass or EPS.
- UV Sensitivity: PIR can degrade when exposed to UV light, requiring protective measures in some scenarios.
- Installation Precision: Achieving maximum insulation effectiveness requires careful installation.
- Environmental Impact: Chemicals used in PIR production may have environmental repercussions.
- Flammability: Despite being relatively fire-resistant, PIR can still ignite under certain conditions, necessitating adequate safety precautions.
UK PIR Insulation comparison chart
There's a PIR board for virtually every part of your building envelope, from stud walls and floors to roofs and lofts.
This chart provides a detailed comparison of various PIR insulation boards available in the market from brands like Xtratherm, Celotex, Recticel, Kingspan, Ecotherm, and IKO. From their thermal properties to compressive strength, and from their versatility in application to their dimensions, we've gathered data from leading manufacturers to help you make an informed decision.
Manufacturer |
Product |
Thickness Range (mm) |
R-Value Range (m²K/W) |
Thermal Conductivity (W/mK) |
Size (mm) |
Compressive Strength at 10% (kPa) |
Application |
Celotex |
20 - 40 |
0.5-1.8 |
0.022 |
2400 x 1200 |
140 |
Floor |
|
Celotex |
50 - 100 |
2.25-4.5 |
0.022 |
2400 x 1200 |
140 |
Floor |
|
Celotex |
110 - 200 |
5-9.05 |
0.022 |
2400 x 1200 |
140 |
Floor |
|
Ecotherm |
25 - 150 |
1.14 - 6.82 |
0.022 |
2400 x 1200 |
140 |
Walls |
|
IKO |
IKO enertherm ALU |
30 - 200 |
1.35 - 9.05 |
0.022 |
2400 x 1200 |
≥ 175 |
Walls |
Kingspan |
40 - 100 |
1.80 - 4.50 |
0.022 |
1200 x 450 |
140 |
Cavity Wall |
|
Kingspan |
20 - 150 |
0.90 - 6.8 |
0.022 |
2400 x 1200 |
140 |
Walls |
|
Kingspan |
20 - 150 |
0.90 - 6.8 |
0.022 |
2400 x 1200 |
140 |
Pitched Roof |
|
Kingspan |
30 - 150 |
1.10 - 6.25 |
0.024 - 0.027 |
1200 x 600 |
150 |
Flat Roofs |
|
Kingspan |
25 - 160 |
1.10 - 7.25 |
0.022 |
1200 x 600 |
150 |
Flat Roofs |
|
Kingspan |
25 - 160 |
0.90 - 6.65 |
0.024 - 0.027 |
1200 x 600 |
150 |
Flat Roofs |
|
Kingspan |
20 - 150 |
0.90 - 6.8 |
0.022 |
2400 x 1200 |
140 |
Floors |
|
Recticel |
20 - 160 |
1.10 - 7.25 |
0.022 |
2400 x 1200 |
140 |
Floors |
|
Recticel |
20 - 160 |
1.35 - 4.50 |
0.022 |
1200 x 450 |
120 |
Cavity Walls |
|
Recticel |
75 - 140 |
3.40 - 6.35 |
0.022 |
1200 x 450 |
120 |
Cavity Walls |
|
Recticel |
30 - 160 |
1.15 - 6.65 |
0.024 - 0.026 |
1200 x 600 |
≥150 |
Flat Roofs |
|
Recticel |
20 - 150 |
0.75 - 6.25 |
0.024 - 0.026 |
1200 x 600 |
≥ 150 |
Flat Roofs |
|
Recticel |
30 - 160 |
1.35 - 7.25 |
0.022 |
2400 x 1200 |
≥150 |
Flat Roofs |
|
Unilin (Formally Xtratherm) |
20 - 150 |
1.1 - 5.65 |
0.022 |
2400 x 1200 |
150 |
Stud wall |
Comparing PIR to Other Insulation Board Types
When it comes to insulation, one size does not fit all. Each type of insulation board offers unique benefits and limitations, making the choice highly dependent on specific project requirements.
PIR vs EPS Insulation
Feature |
PIR |
EPS |
Summary |
Cost |
Generally, more expensive |
Less expensive |
EPS is less expensive, but PIR offers better long-term value through efficiency. |
Performance |
Higher R-value per inch, excellent moisture resistance and strength |
Good insulation but lower R-value per inch compared to PIR |
PIR provides better insulation with less thickness. |
Specifications |
Higher fire rating, making it safer in applications where fire risk is a concern |
Lower fire rating compared to PIR |
PIR has superior fire safety ratings. |
Applications |
Suitable for areas requiring maximum insulation in minimal space (e.g., flat roofs) |
Versatile, but not as efficient in space-constrained applications |
PIR is more suitable for space-constrained applications. |
Energy Cost Savings |
Superior thermal efficiency leads to significant savings on energy bills over time |
Lower initial cost but less effective in reducing long-term energy bills |
PIR offers greater long-term savings on energy bills. |
So, which is better, EPS or PIR?
The lower the R-value, the better the insulation! PIR may be more expensive to buy, it outperforms EPS in all other aspects.
PIR vs HP+
Feature |
PIR |
HP+ |
Summary |
Cost |
Generally, more expensive than HP+ |
Cheaper than PIR but more expensive than standard EPS, yet cost-effective for its efficiency |
HP+ offers a middle ground in cost, balancing efficiency, and affordability. |
Performance |
Superior thermal efficiency with a high R-value per inch |
Enhanced thermal performance due to carbon additive, offering lower U-values |
PIR and HP+ are closely matched in performance, with space availability being a determining factor. |
Specifications |
Superior fire resistance compared to standard HP+ |
Lower fire rating compared to PIR, HP+ is rot-proof, mould, water and moisture resistant |
PIR excels in fire resistance; Both PIR and HP+ provide same level of resistance. They are made of closed cells, so they do not absorb water. |
Applications |
Versatile for roofs, walls, and floors |
Suitable for floors, walls, and roofs |
HP+ and PIR both offer broad applications, with the choice often dictated by specific project requirements. |
Energy Cost Savings |
Significant savings on energy bills due to high thermal efficiency |
Can achieve similar energy cost savings to PIR with a thicker board |
HP+ can offer similar energy cost savings to PIR when the project allows for the use of thicker insulation material. |
So, which is better, PIR or HP+?
Ultimately, for projects prioritising space and efficiency, PIR is the superior choice. However, HP+ is a strong contender for those seeking a balance between cost, performance, and flexibility in installation thickness. Both materials offer significant potential for energy cost savings, with the decision often boiling down to the specific application and project requirements.
PIR vs XPS
Feature |
PIR |
XPS |
Summary |
Cost |
Can be more expensive but offers better performance per unit cost |
More expensive depending on specifications |
PIR often provides better value in terms of performance per unit cost. |
Performance |
Higher R-value per inch, providing better insulation |
Excellent moisture resistance but lower R-value per inch than PIR |
PIR provides better insulation efficiency. |
Specifications |
Superior fire resistance |
Excellent compressive strength, suitable for use below grade |
XPS is preferred for its compressive strength, but PIR has better fire resistance. |
Applications |
Favoured for its thermal insulation and fire performance |
Preferred where water resistance and high compressive strength are critical |
XPS is ideal for specific applications, but PIR is more versatile. |
Energy Cost Savings |
Leads to greater long-term savings on energy bills |
Higher upfront costs with less impact on long-term energy savings |
PIR offers greater long-term savings on energy bills. |
So, which is better, PIR or XPS?
XPS and PIR are closely matched in terms of moisture resistance and compressive strength, but PIR edges ahead with its thermal performance and fire safety ratings. For projects where thermal efficiency is paramount, PIR stands out as the more effective solution.
PIR vs Phenolic
Feature |
PIR |
Phenolic Foam |
Summary |
Cost |
Generally, more affordable |
Usually more expensive due to superior fire performance and manufacturing process |
Phenolic Foam is more expensive, but PIR offers a competitive balance of cost and performance. |
Performance |
Offers a balance of thermal performance, moisture resistance, and cost |
Exceptionally low thermal conductivity (high R-value) and excellent fire resistance |
Phenolic Foam has superior thermal and fire performance, but PIR is highly competitive. |
Specifications |
Moisture resistance and durability under various conditions |
Superior fire resistance and thermal efficiency |
Phenolic Foam excels in fire resistance and thermal efficiency, but PIR is more versatile. |
Applications |
Versatile for residential and commercial projects |
Used in high-specification buildings for fire safety and thermal efficiency |
PIR is more versatile, fitting a broader range of applications. |
Energy Cost Savings |
Significant potential for energy cost savings, more accessible to a wide homeowner range |
Significant potential for energy cost savings, but higher cost may limit accessibility |
PIR is more accessible for energy cost savings across more projects. |
So, which is better, PIR or Phenolic Insulation?
Phenolic foam offers excellent fire performance and a slightly better thermal efficiency than PIR. However, its higher cost, susceptibility to moisture, and more complex installation process can make PIR a more practical choice for a wide range of applications.
Is PIR insulation right for me?
Choosing the right insulation material is a crucial decision in any construction or renovation project. As we've explored, PIR insulation stands out for its exceptional balance of thermal efficiency, fire safety, and versatility across different applications. While other materials like EPS, HP+, XPS, and phenolic foam have their respective strengths, PIR often emerges as the best overall choice for homeowners and builders looking to enhance energy efficiency and reduce long-term costs.
The comparison highlights the importance of considering not just upfront costs but also long-term savings and performance benefits. Ultimately, the "winner" in the insulation race will depend on specific project requirements, but PIR insulation is undoubtedly a top contender for those seeking to maximise energy efficiency and building performance.
FAQs
Can PIR insulation be used in all areas of a building?
Yes, PIR insulation is versatile and can be used in various parts of a building, including roofs, walls, and floors. Its excellent thermal efficiency and moisture resistance make it suitable for both interior and exterior applications.
How does PIR insulation compare to fiberglass insulation in terms of R-value?
PIR insulation typically offers a higher R-value per inch than fiberglass insulation, meaning it provides greater thermal resistance and thus better insulation in a thinner layer. This makes PIR an efficient choice for areas where space is limited.
Is PIR insulation environmentally friendly?
While PIR insulation involves chemicals in its production, many manufacturers are moving towards more environmentally friendly blowing agents and materials. Its high efficiency also means that buildings require less energy for heating and cooling, contributing to overall energy savings.
Can PIR insulation be recycled?
Recycling PIR insulation can be challenging due to its chemical composition and the blowing agents used. However, efforts are being made to improve recyclability and manage end-of-life disposal in an eco-friendly manner.
How long does PIR insulation last?
PIR insulation is known for its durability and can last the lifespan of a building if properly installed and protected from UV light and physical damage. Its resistance to moisture and mould contributes to its longevity.
Does PIR insulation need a vapor barrier?
Due to its closed-cell structure, PIR insulation inherently resists moisture absorption, reducing the need for an additional vapor barrier in many applications. However, building codes and specific project requirements should always be consulted.
Is PIR insulation fire resistant?
PIR insulation has better fire resistance compared to other foam-based insulations like EPS or XPS. It is treated with fire retardant chemicals, which improve its fire performance. Nonetheless, it's important to comply with all applicable building codes and standards regarding fire safety.
How does PIR insulation handle moisture and water exposure?
Thanks to its closed-cell structure, PIR insulation is less prone to water absorption, making it an excellent choice for damp or prone-to-flooding areas. However, prolonged exposure to water should be avoided to maintain its insulating properties.
Can PIR insulation be cut to fit custom shapes and spaces?
Yes, one of the advantages of PIR insulation is its ease of handling and cutting. It can be easily cut with a sharp knife or saw to fit custom shapes and spaces, making it adaptable to various installation requirements.