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Our Inverted Roof Insulation Solutions

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Choosing the best inverted roof insulation is important for any project

The OPTIM-R E Inverted Roofing System is our latest innovation in vacuum insulation technology . The OPTIM-R Vacuum Insulation Panels (VIPs) are encapsulated in a durable protective coating, providing increased robustness and easier handling, making them the ideal solution for constructions with limited depth or space.

Compare inverted roof insulation boards

Product                                                                                    

Type                                                                                                                                     

Thermal Conductivity                                                      

Compressive Performance                                                              

Insulation Boards

Inverted Roof Insulation

Our inverted roof insulation solutions include Vacuum Insulation Panels (VIPs) and a range of rigid extruded polystyrene (XPS) insulant products

Interested in learning more?

U-value calculator
Technical Information

U-value Calculator

We provide U-value calculations free-of-charge to show compliance with current Building Regulations, Standards and best practices. 

Kingspan Technical Services
Technical Information

Technical Services

Contact details for technical enquiries relating to insulation boards, cavity closers and membranes.

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Education & Training

CPD's

We have a number of CPDs that can be booked to further your knowledge.

Our range of rigid extruded polystyrene insulation (XPS) products are suitable for use in a variety of inverted roof systems, including green roofs and protected membrane flat roofs. With minimal water absorption and high compressive strength, they are built to withstand the freeze-thaw process, ensuring long-term performance. The insulation boards are easy to handle and install compared to other commonly used insulants, making them perfect for both new build and refurbishment projects.

Our product range also includes a water-infiltration reduction membrane, specifically designed for inverted roofing systems.

Benefits of inverted roof insulation:

  • Protects waterproofing membrane
  • High compressive performance
  • Compatible with green roof systems
  • Resistant to the passage of water vapour
  • Ideal for new build and refurbishment projects

Image: CEG

OPTIM-R E Inverted Roofing System

 

Vacuum Insulation Panels

 

Declared -

0.008 W/mK

Design -

0.009 W/mK

declared compressive stress is 150kPa

 

Kingspan GreenGuard GG300

 

Rigid extruded polystyrene insulation                                                          

Declared -

0.033 W/mK (30 - 180 mm)

Design - 

0.035 W/mK (30 - 180 mm)

declared compressive strength is 300kPa

Kingspan GreenGuard GG500

Rigid extruded polystyrene insulation

Declared -

0.034 W/mK (50 & 60 mm)
0.036 W/mK (80 & 100 mm)

Design - 

0.036 W/mK (50 & 60 mm)
0.038 W/mK (80 & 100 mm)

declared compressive strength is 500kPa 

Aquazone

Water-infiltration reduction membrane with a water vapour resistance of 0.01 Sd

n/a

n/a

 

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  1. Home
  2. Inverted Roof Insulation Boards

How to insulate inverted roofs

Find out what U-values inverted roofs should achieve and which insulation products are best suited.

Knowledge Article6 min read
What Are U-Values, R-Values And Lambda Values Article- 4:3

What are U-values, R-values and Lambda Values?

Lambda, R-values, U-values, Thermal Conductivity and Thermal Resistance simplified in one article

Knowledge Article4 min read
kingspan-who-we-are

Types of Insulation - a Guide

We manufacture five types of insulation for walls, floors and roofs.

Knowledge Article4 min read
Optimum performance insulation solution for protected membrane flat roofs

OPTIM-R E Inverted Roofing System

Optimum performance insulation solution for protected membrane flat roofs
Rigid extruded polystyrene (XPS) insulation
Aquazone Water Infiltration Reduction Membrane.

Kingspan GreenGuard

Rigid extruded polystyrene (XPS) insulation

Aquazone Water Infiltration Reduction Membrane

Aquazone Water Infiltration Reduction Membrane.

Frequently Asked Questions