Close
3M™ Hollow Glass Microspheres – Grade S28HS are high-strength, thick-walled hollow glass microspheres engineered for applications where mechanical durability and long-term performance are critical. In roofing systems, S28HS offers an optimal balance between weight reduction, thermal insulation, and compressive strength, making it especially suitable for high-traffic roofs, industrial rooftops, and heavy-duty protective coatings.
Unlike ultra-low-density grades, S28HS is designed to withstand higher mechanical stresses, allowing its use in reinforced heat-reflective roof coatings, waterproofing layers, and lightweight cementitious roof grouts without compromising strength or service life.
Zeolite Silver Antimicrobial Powder/ Ag-Zeolite Powder
1318-02-1
215-283-8
3824.99.00
not classified as dangerous goods
2.1–2.3 g/cm³
4–5
0.1%
S28HS is well suited for cool roof and thermal barrier coatings where durability is essential.
Functional role:
Creates stable air voids to reduce heat transfer
Allows thicker coating build without sagging or cracking
Maintains coating integrity under thermal expansion and contraction
Typical systems:
Epoxy and PU roof top coats
Elastomeric waterproofing membranes
Industrial heat-reflective coatings for metal and concrete roofs
In cementitious and polymer-modified systems, S28HS provides lightweight reinforcement with strength retention.
Functional role:
Reduces dead load while maintaining compressive performance
Improves workability and placement of roof mortars
Lowers shrinkage stress in thick roof sections
Typical systems:
Structural roof screeds
Repair mortars for industrial roofs
Lightweight concrete toppings on RCC slabs
Roof protection layers under solar panel installations
Traffic-resistant roof decks
Protective overlays exposed to mechanical wear
| Property | Typical Value |
|---|---|
| Composition | Soda-lime borosilicate glass |
| Particle morphology | Hollow spheres (thick-walled) |
| True density | ~0.28 g/cc |
| Bulk density | ~0.16 g/cc |
| Crush strength (90% survival) | ~3,000 psi |
| Average particle size | ~30 microns |
| Thermal conductivity | Low |
| Combustibility | Non-combustible |
| Color | White |
Enables lightweight roofing systems without sacrificing durability.
Air-filled microspheres disrupt heat flow, reducing roof heat gain.
Thick-walled structure withstands higher loads, abrasion, and impact.
Lightweight fillers reduce internal stresses from thermal cycling.
Spherical particles improve flow, pumpability, and leveling.
Inorganic glass structure resists UV degradation, moisture ingress, and weathering.
Optimize dosage based on mechanical and thermal performance requirements.
1 – 5% by volume of total formulation
Suitable for high-build, durable roof coating systems
1– 3% replacement of conventional fillers (by volume)
Balances weight reduction with strength retention.
Refer to SDS for complete safety information.