Semi Open Cell EPDM Sponge Seals

Advanced Seals & Gaskets Ltd produce and supply some of the highest quality seals in the UK, working with a multitude of reputable material manufacturers and suppliers, enabling us to offer seals manufactured using a range of high-quality EPDM sponges in various densities and grades.  One of the EPDM sponges we can offer is Semi-Open Cell EPDM, sometimes also called Semi-closed cell sponge or semi-open cell foam. 

This material is manufactured in block form, which we can split down into sheets or join together and then split to produce continuous lengths or rolls of materials in thicknesses starting at just 1.5mm from which seals can be cut.  Semi-Open Cell EPDM sponge seals can take the form of gaskets, washers, strips, pads or fabricated components, which are all designed for the purpose of preventing leaks or the ingress of air, fluids and gas. 

All our Semi-Open Cell EPDM sponge seals are made to order and are produced by following samples or drawings provided by customers to ensure the final product perfectly fits the application.  As each form of sponge seal needs to be manufactured using a different process, ASG has invested heavily in various machinery allowing us to offer seals in both high and low volumes, many of which can be supplied in a plain finish, laminated in layers to create other thicknesses,  laminated to other materials or coated with a choice of self-adhesives and foils prior to the seals being cut.

What are Semi Open Cell EPDM Sponge Seals?

Semi-Open Cell EPDM is an extremely soft and flexible grade of EPDM sponge rubber, still manufactured from the chemical components Ethylene Propylene Diene Monomer, but using a different manufacturing process to create the mixture of open and closed cells throughout the material. 

The cell structure of Semi-Open Cell EPDM is created in the manufacturing process by physically "bursting" the closed-cell structure in order to create a product that is softer and therefore easier to compress than the more traditional medium or firm grade EPDM sponge rubber, making them great for creating sealing components such as seals. 

Semi-Open Cell EPDM sponge seals are a device or substrate that is used to join surfaces together, acting as a separator or a barrier to prevent liquids, particles or gases from escaping or penetrating the application. ‘Seal’ is a generic term for products often taking the form of cut gaskets, strips, washers, extruded or moulded profiles, edge trims and cord.  Most of the sponge seals produced by Advanced Seals and Gaskets can be supplied with a choice of self-adhesives which assists with placement of the seal and holding it in position.

Semi Open Cell Epdm Sponge Seals

Product Enquiry

For information on Semi Open Cell EPDM Sponge Seals please complete the following quick enquiry or call us on +44(0)1384 252555.






    Product Specification & Key Characteristics

    • Colour: Black
    • Cell Structure: a combination of open and closed cells
    • Temperature Range: -40 ˚C and 100˚C
    • Density: 70 - 130 kg/m3
    • Fire-resistant: (FMVSS302 - FIAT 50433)
    • Resistances: Ozone, UV, high and low temperatures, electricity

    Full technical data can be supplied upon request,
    or downloaded from our online portal.

    Help and guidance

    If you would like to speak to a representative to discuss your specific application or requirements please call our sales office direct on 01384 469100, alternatively you can send an E-mail. Simply click on the link and forward us your details along with your question and we will contact you immediately.

    Samples - Technical Semi Open Cell EPDM Sponge Seals

    Samples can be submitted for testing upon request.

    Call now for sample requests or further help.

    Why use Semi Open Cell EPDM Sponge Seals?

    Semi-Open Cell EPDM sponge seals are designed to prevent the escape or ingress of dust, air, liquids or gases when compressed between irregular surfaces - very much used in the same way as a gasket. Seals can also be used as an aid for shock, noise and vibration dampening in a range of industries. 

    Semi-open cell EPDM sponge seals offer similar flexibility and compressibility to an open-cell foam, but under compression, they have excellent sealing capabilities more like a closed cell sponge. In order for the material to work effectively, it needs to compress and fill the entire space to create pressure and an airtight protective seal. 

    Semi-open cell sponges are durable and offer the excellent ozone and weathering resistance of a standard EPDM, but with a slower and better recovery following compression which is suited to sealing applications.  Semi-Open cell EPDM sponge can be taken as complete sheet or roll form, or as a pre-cut cut or fabricated seals, suitable for use as a solution to indoor and outdoor sealing applications, providing protection against air, dust and moisture.

    Benefits of using Semi Open Cell EPDM Sponge

    • Resistance to ozone and UV light
    • Soft and compressible 
    • Combination of open and closed cells
    • Excellent acoustic performance
    • Good compression set
    • Seals against air, dust & moisture
    • Converted onsite into a range of thicknesses and products

    The Advantages of using Semi Open Cell EPDM Sponge Seals

    Semi-Open Cell EPDM seals are produced using  Semi-Open Cell EPDM sponge material which has a super-soft nature, providing excellent sealing capabilities once compressed.  Due to low compression load, the foam can compensate for dimensional deviations in substrates and can, therefore, be applied to both rough, smooth and low energy surfaces.  The material offers resistance to Ozone and UV, has a wide working temperature range of -40 ˚C and 100˚C and can be used for sealing against water, dust and air. 

    Being such as soft and conformable material, Semi-Open Cell EPDM sponge seals can be used to fill gaps and irregularities between two surfaces and to provide a solution to unwanted rattles, noise, vibrations, to seal against air, gas, dust and liquids, and can also be used to cushion between moving parts to reduce friction and damage to components and equipment, they are often found used within HVAC systems, the automotive industry and as window seals, to name a few.

    Grades of EPDM Sponge Available

    ASG stock a variety of other grades and densities of EPDM sponge which can call be used to manufacture gaskets each suited to individual applications. These include firm grade, high temperature and semi-open cell varieties:

    Medium Density EPDM is available in black or white colour options. EPDM sponge is a strong, synthetic material that has a closed-cell structure making it an ideal material for internal and external sealing applications where minimal compression is required for the material to work as an effective seal.  Medium-density EPDM sponge has a density of 90 – 140kg/m3, an operating temperature range of -20°c to +85°c and is flammability tested to FMVSS 302.

    High-Temperature EPDM Foam is closed cell and highly flexible even at low temperatures, with an amazing temperature range of -50°c to +128°c.  High-Temperature EPDM foam has many excellent mechanical characteristics including thermal and insulation properties, making this material ideal for many industries and applications including HVAC, Refrigeration, Pipeline, Automotive, White goods and Building & construction, etc.

    Firm Grade EPDM Foam is a more resilient material that will not compress as much as the standard grades under load, also this material benefits from increased tear strength and suits some of the more demanding applications such as Automotive, White Goods, Marine, Defence, Building and Construction, etc

    For further information, you can view our online specification sheets or speak to a member of our sales team.

    Have a Question about Semi Open Cell EPDM Sponge Seals?

    Please contact us using the form below or by calling us on +44(0)1384 252555.