Product Facts
- Product Name
- Expandafoam - Closed Cell Polyethylene Joint Filler
- Price
- 0 AUD
- Availability
- In Stock
- Condition
- New
- Category
- Construction Materials > Joint Fillers & Sealants
- Seller
- Fosroc Workspace
Expandafoam - Closed Cell Polyethylene Joint Filler
Expandafoam is a closed-cell polyethylene joint filler for use as an expansion joint filler in brick and blockwork, isolation joints and as back-up strips for elastomeric sealants placed in narrow joints in concrete floors subject to foot traffic and light wheel loads. Key advantages include readily compressible material, low load transfer, easily cut on-site, excellent recovery after compression, non-absorbent, rot proof, CFC free, and fast simple application with no special tools, heating or drying required. Flexible, long lasting, self-sealing to minor substrate blemishes with high puncture resistance and joint water pressure resistance.
Expandafoam is a closed-cell polyethylene joint filler for use as an expansion joint filler in brick and blockwork, isolation joints and as back-up strips for elastomeric sealants placed in narrow joints in concrete floors subject to foot traffic and light wheel loads. Key advantages include readily compressible material, low load transfer, easily cut on-site, excellent recovery after compression, non-absorbent, rot proof, CFC free, and fast simple application with no special tools, heating or drying required. Flexible, long lasting, self-sealing to minor substrate blemishes with high puncture resistance and joint water pressure resistance.
Brand: Fosroc
Product Data (OpenAI Spec)
View Full JSON Spec ↗Specifications
| Condition | new |
|---|---|
| Category | Construction Materials > Joint Fillers & Sealants |
Product Intelligence
Expandafoam Closed Cell: Technical Details, Specifications, Features
Product Overview
Expandafoam Closed Cell is a medium density, closed cell polyethylene foam rod supplied in circular section cords of varying diameters. It is manufactured and supplied by Fosroc and distributed by Parchem Construction Supplies Pty Ltd. This product is primarily designed as a bond breaker and joint profile former to support elastomeric sealants in expansion joints between all common building materials.
Key Applications
Expandafoam Closed Cell serves multiple construction applications:
- Roads, Bridges, and Roof Joints: Used as a backing strip for non-traffic-bearing expansion joints
- External Walling and Cladding: Functions as a backing strip for expansion joints, gap filler for open joints prior to cold applied joint sealant application, and as a compressible, low load transfer joint filler in joints surrounding brick infill panel walling
- Glazing: Serves as a gap filler and backing strip to support perimeter sealing around frames and sub-frames
- Internal Finishes: Used as a gap filler and backing strip to provide support to sealants in partition joints and around work tops, baths, and other internal finishes
Core Advantages
The product offers several key benefits:
- Compatible with all elastomeric sealants
- Readily compressible - provides flexibility during installation
- Low load transfer - suitable for non-structural applications
- Non-gassing - does not release volatile compounds
- No water absorption - provides durability in wet conditions
- CFC free - environmentally safe manufacturing
Physical Properties and Specifications
| Property | Specification |
|---|---|
| Form | Compressible, closed cell polyethylene foam rod |
| Colour | White |
| Weathering Test | No disintegration |
| Water Absorption | 0.01 ml/cm³ |
| Service Temperature Range | Minus 80°C to 100°C |
| Nominal Density | 25 kg/m³ |
| Material Composition | Closed-cell polyethylene |
| UV Resistance | Resistant to long-term UV exposure |
| Migratory Chemicals | Contains no migratory chemicals that could adversely affect joint sealants |
| Cross Section Shape | Circular section providing a convex face for optimal elastomeric sealant performance |
Design Criteria and Installation
Joint Width and Diameter Selection
Expandafoam Closed Cell should always be installed into a joint under compression to ensure that applying the joint sealant will not displace the foam. This is achieved by compressing Expandafoam Closed Cell by 25% when installing into a joint or by using foam 1/3 larger than the joint size.
The following sizing chart provides guidance:
| Joint Width (mm) | Expandafoam Closed Cell Diameter (mm) |
|---|---|
| 5 to 8 | 10 |
| 9 to 11 | 13 |
| 12 to 13 | 15 |
| 14 to 17 | 20 |
| 18 to 20 | 25 |
| 21 to 27 | 30 |
| 28 to 35 | 40 |
| 36 to 45 | 50 |
Sealant Depth Requirements
The sealant depth must be a minimum of 6 mm at the thinnest section of the sealant bead (above the centre of the Expandafoam), with a minimum bonding depth at the joint face of 6 mm on smooth glass and metal surfaces, and 12 mm on porous or rough surfaces. For larger joints, the depth of the joint face should normally be half the joint width.
Installation Process
When used as a backing strip, Expandafoam Closed Cell is simply push fitted back into the joint. The cord diameter used should be 20 to 30% greater than the joint width. The circular section of Expandafoam Closed Cell provides a convex face to ensure that applied elastomeric sealants are given optimum shape for minimum strain as the joint moves.
Important: Do not use sharp objects when fitting Expandafoam Closed Cell, as any damage to joint backing may allow air voids to be formed in sealant. Correct fitting will result in an oval cross section, with depth of Expandafoam Closed Cell being greater than the nominal joint width, so care must be taken to ensure that correct sealant dimensions are maintained after fitting.
Limitations
- Not suitable for hot pour sealants - Expandafoam Closed Cell is not compatible with hot pour sealant applications
- Traffic-bearing applications - Applications where joint backing must provide continual support for the joint sealant, such as water retaining structures or floor joints subject to traffic, require Stiffjoint, a semi-rigid filler alternative
- UV exposure - Expandafoam Closed Cell is not resistant to long-term UV exposure
Supply and Availability
Expandafoam Closed Cell is available in the following sizes and roll lengths:
| Size | Material Code |
|---|---|
| 10 mm x 250 m roll | FC700973-UNIT |
| 13 mm x 100 m roll | FC700974-UNIT |
| 15 mm x 100 m roll | FC700975-UNIT |
| 20 mm x 60 m roll | FC700976-UNIT |
| 25 mm x 50 m roll | FC700977-UNIT |
| 30 mm x 50 m roll | FC700978-UNIT |
| 40 mm x 2 m strip | FC700979-UNIT |
| 50 mm x 2 m strip | FC700980-UNIT |
Other sizes may be available upon application. For applications where dimensions do not meet standard requirements, Fosroc provides technical consultation.
Functional Characteristics
Bond Breaker Function: Expandafoam Closed Cell serves as a protective material that prevents unwanted adhesion between surfaces. Its primary function is to inhibit sealant contact with the back of joints, which is critical for optimizing sealant performance and allowing proper movement accommodation within sealed assemblies.
Closed Cell Structure: The foam composition characteristic prevents water absorption and migratory chemical release, ensuring long-term durability and compatibility with sealant systems.
Compressibility: The foam's readily compressible nature allows it to accommodate varying joint sizes while maintaining structural support for the sealant during thermal and mechanical movement cycles.
References
- [1] Fosroc_Expandafoam_Closed_Cell_TDS.pdf
- [4] Fosroc_Flamex_One_TDS.pdf
- [6] Fosroc_Hydrocor_Corkjoint_Type_3_TDS.pdf
- [8] Fosroc_Expandafoam_TDS.pdf
- [12] Fosroc_Hydrocell_TDS.pdf