Rigid Foam…

Rigid Foam: Insulation, structural, fire resistant, phenolic and modelling foams. Acoustafoam offers a range of rigid foams in a sheet and CNC cut components to meet many industrial applications and projects.

Rigid polyurethane (PUR) and polyisocyanurate (PIR) insulation products are highly efficient, lightweight, and many have the ability to bond to most materials. They have excellent thermal conductivity and high strength to weight ratio, combined with great manufacturing versatility. Acoustafoam provides a range of products used worldwide. As a result, PIR/PUR insulation products are the first choices for most construction insulation applications.

The first commercial applications for polyurethanes were developed in the middle of the 20th century. Since then they have been finding use in an ever-increasing number of applications in industries such as construction, automotive, refrigeration, furniture and footwear. Polyurethanes are extremely versatile and are found all around us in many everyday applications.

Rigid insulation polyurethane foam. This range has very low thermal insulation coefficients, making them the material of choice for refrigeration applications. The foam is used to make composite panels for cold storage rooms and isothermal truck bodies.

For building insulation, we have CE-Marking approved polyurethane foam.
These foams, are available in densities of 33 to 60 kg/m3.
The thermal conductivity of polyurethane foam (between 0.022 and 0.028 W/m/k) makes it the best insulator.

Structure Rigid polyurethane foams

This type of foam is used as structural foam in a significant number of applications: Rail industry, boat-building, construction, polyester furniture, bus and coach Builders, aircraft and military to name but a few. These foams are commonly used as core and fill materials for composite parts.


Chemical resistance to many solvents, oils, styrene and polyester resins.
Excellent mechanical characteristics and compression.
High resistance to moisture and mildew (long lasting).
Densities range from 35 to 200 kg/m3 and include M1 fire rated line up.
Phenolic rigid foams.

The fire performance of phenolic foam is exceptional. It combines zero or very low flame spread with negligible smoke emission and a very low level of toxic gas emission. Phenolic foam is a thermoset material meaning it will not run melt or drip when it comes into contact with a fire source.

Phenolic foam can, in an appropriate form, achieve all the following European fire certifications:

  • EN 13501-1 Euro class B-s1-d0.
  • UK Class O / Low Risk in Scotland.
Dutch NEN 6065/6066 Class 1.
  • German B1.
Belgian A1.
  • French M1.
  • Scandinavian NT 036 Class 1.
  • AS / NZS 1530 Part 3 0,0,0,0-1.
  • AS 3837 BCA Class 1

The phenolic foam used in factory engineered composite panels can achieve up to 2 hours of fire resistance (insulation/integrity) in the 3m furnace test.

As part of a ventilated rain screen façade or a rendered external insulated wall system, the phenolic foam can limit fire propagation to the outside of the building. Through testing to BS 8414 and BR 135 phenolic insulated systems can meet the UK Building Regulation requirements for use in high-rise construction (above 18metres).

Phenolic foam emits exceptionally little smoke when exposed to fire and is capable of meeting or exceeding all international building regulation requirements.

Toxic gas emission from phenolic foam is limited to carbon dioxide and carbon monoxide with very low levels of other gases. Phenolic foams can achieve very low toxic gas ratings in tests such as UK Naval Engineering Standard NES 713 and Scandinavian Nord Test NT036.

Thermal characteristics

Closed cell phenolic offers the best thermal resistance, i.e. the lowest thermal conductivity, of any readily available building insulation material.

This is because of the closed cell structure, very small cell diameter, low thermal conductivity material and gas permanently encapsulated in cells.

Closed cell phenolic foam is also notable in that the thermal properties do not deteriorate noticeably with time. Closed cell phenolic foam offers the following benefits.

The thermal conductivity or Lambda (λ) values range from 0.018 W/m. K depending on national certification requirements. Excellent low thermal conductivity allows a reduction in long-term energy costs while conforming to standard build constructions, as thin panels give excellent insulation value.

Closed cell phenolic foam shows up to 100% more thermal resistance than other conventional insulation materials.

Higher thermal efficiency allows reduced insulation thicknesses to be used thereby saving valuable space, and enabling current and future building codes for energy, cost and CO2 saving to be easily met.

Structural Strength

Phenolic foams have an excellent strength/density relationship being lightweight but sturdy. Higher density phenolic foams are typically used for, pipe supports, ducting panels, duct supports, steel faced composite panels (including walk-on ceilings).

Structural phenolic foam is typically made in 60, 80, 120 and 160 kg/m3 densities.

For the highest density foams, 1m² of the product is capable of supporting the static weights:

80 kg/m3 – 64 tonnes. 120 kg/m3 – 112 tonnes. 160 kg/m3 – 225 tonnes.
This data demonstrates the excellent structural performance of phenolic foam.
Phenolic foam has been used successfully in structural applications for over 20 years.
Phenolic foam has been used successfully in insulation systems where moisture resistance is a critical issue.

The reasons for this excellent performance is that phenolic foam has a low water vapour performance and is therefore highly resistant to the passage of water vapour.
Phenolic foam has low water absorption which takes place predominantly in the cut/broken surface cells of the foam.

Phenolic foam is non-wicking meaning if water enters the insulation system due to the vapour barrier becoming punctured; any moisture ingress is limited and confined to the damaged area. This ensures moisture does not build up and compromise the whole system.


Phenolic foam has a very low environmental impact per unit thermal performance when compared with many other insulation materials and is available in both CFC-free and HCFC-free form. Phenolic foam can help significantly reduce the CO2 emissions from new and existing buildings. Phenolic foam can make a significant contribution to the achievement of global, regional and national CO2 emission reduction targets.

Construction Sector

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