FILL IT
Bostik Fill It Expanda Foam is a multi-purpose, self-expanding foam filler. This one-component polyurethane foam cures to an airtight, moisture-resistant seal and can be used indoors or outdoors. The straw applicator helps apply foam into small or large gaps, including hard-to-reach areas. Once cured, the foam can be cut, sanded, plastered or painted for a neat finish.
White
Product overview
Bostik Fill It Expanda Foam is a one-component expanding polyurethane foam with an off-white finish. It expands after application, cures by moisture and forms an airtight, moisture-resistant seal. The 750ml aerosol can yields up to 50L, with a skin time of approximately 8–12 minutes at 20°C and 60% relative humidity.
Surface Compatibility
Suitable for use on concrete, brick, stone, plaster, wood, metal and many plastics, including EPS, XPS, rigid PU foam and uPVC. Surfaces should be clean, dry and free from dust, grease and loose material before application.
Features & benefits
Interior or exterior usage
Fills large or small gaps
Seals, fills, bonds, and insulates
Downloads & resources
Bostik DIY Australia Insulate - Fill It Technical Data Sheet (130.36 KB)
Bostik DIY Australia Insulate - Fill It Safety Data Sheet (97.4 KB)
How to Use
Preparation
- Ensure all surfaces are clean, dry and free from dustand grease. Remove all loose materials (including old filler) from the areas to be filled.
- Moisten surfaces with a water sprayer prior to application to optimise expansion and adhesion.
Application
- Shake aerosol can vigorously for at least 20 seconds.
- Screw straw applicator onto can.
- Fill holes and cavities to 65% as foam will expand.
- Shake can regularly during application.
- If you need to work in layers, moisten each layer before applying the next layer.
- Cures at a rate of 1 hour per 30mm bead at 20◦
Use as a foam filler, gap filler foam or sealing foam for filling cavities, sealing openings in roof construction, applying sound-absorbing layers, creating acoustic baffles and improving thermal insulation in cooling systems. It can also be used for foam filling in gaps where expansion is needed.
Limitations
Not suitable for PE, PP, PC, PMMA, PTFE, soft plastics, neoprene or bituminous substrates. Do not use where there will be permanent water load or in cavities with insufficient moisture. Bostik Fill It Expanda Foam is not UV stable, so exposed cured foam should be painted."
FAQs
How do I know how to stick two materials together?
Discover our new Bostik Glue Guide to discover what product to use.
How do you prepare surfaces before gluing?
Before applying adhesive, make sure both surfaces are clean, dry and free from dust, grease, oil, rust, loose material or other contaminants.
Removing residues and preparing the surfaces properly helps improve adhesion and gives the best chance of achieving a strong, durable bond.
How does viscosity affect adhesive performance?
Viscosity refers to how thick or fluid an adhesive is. Lower-viscosity adhesives flow more easily, while higher-viscosity adhesives are thicker and provide greater control during application.
The viscosity of an adhesive can influence how it spreads, fills gaps and performs on vertical surfaces, making it an important factor when selecting the right product for a project.
What is the shelf life of the adhesive I have bought and where can I store it?
The shelf life of adhesives varies from product to product, but typically ranges between one and two years from the date of manufacture when unopened and stored correctly in dry conditions - usually between +5°C and +25°C. Once opened, the life of the product will be more limited – this is dictated by variables including the type of adhesive, how it is stored, and how much adhesive is left unused. For more information, refer to the product’s Technical Data Sheet.
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