The choice between MGO SIP Panels (Magnesium Oxide Structural Insulated Panels) and OSB SIP Panels (Oriented Strand Board Structural Insulated Panels) hinges primarily on performance requirements, particularly regarding fire and moisture. Both are high-performance building systems, but MGO offers superior non-combustibility and water resistance
Comparison Summary
MGO SIPs use Magnesium Oxide board as the exterior sheathing, which is a naturally non-combustible, mineral-based material. OSB SIPs use Oriented Strand Board (a wood composite) which is combustible.
This fundamental difference in sheathing material leads to the core advantages of MGO panels in fire safety, moisture resistance, and indoor air quality. OSB SIPs remain a strong and widely used alternative, typically favored for their lower cost and long-standing availability.
Detailed Comparison Table
| Feature | MGO SIP Panel | OSB SIP Panel |
| Sheathing Material | Magnesium Oxide (MGO) Board | Oriented Strand Board (OSB) |
| Fire Resistance | Superior: Class A1/A Non-Combustible (Zero flame spread, resists fire up to $4$ hours). Does not emit toxic fumes when exposed to fire. | Combustible: Wood-based. Requires chemical treatment for fire rating; emits smoke and fumes when burned. |
| Moisture Resistance | Excellent: Highly resistant to water, mold, and mildew. Does not warp, swell, or delaminate in high humidity. | Low: Prone to swelling, warping, and deterioration from water exposure; susceptible to mold. |
| Structural Strength | Very high. Maintains strength and dimensional stability even when wet. | High when dry, but strength can be compromised by moisture absorption. |
| Toxicity / VOCs | Zero VOCs, Formaldehyde-Free. Considered a “green building material.” | Can potentially off-gas formaldehyde from the adhesives used. |
| Pest Resistance | Highly resistant to insects and termites (mineral-based). | Susceptible to termites and pests (wood-based). |
| Material Cost | Higher (Premium material). | Lower (More common and affordable). |
| Availability | Growing in popularity, but less common than OSB. | Widely available and industry-standard. |
| Weight | Typically heavier than OSB. | Typically lighter than MGO. |
DEC
2025