Frequently Asked Insulation Questions

Fireproofing: Over Steel & For Spray Foam as a Thermal Barrier

What is fireproofing?

Monokote Z-3306 is a cementitious fire protective coating specifically formulated for application over rigid, urethane and polystyrene foam plastics. Monokote MK-6 is single component, spray applied, mill-mixed fire resistive plaster for steel structural members and fluted decking applications.

Do I have to use fireproofing?

Yes, if the foam is required to be protected (thermal barrier for foamed plastics) by provincial building codes (i.e. living space, or crawlspace with a plenum or heat source). ICF (insulated concrete forms) is a styrene foam plastic form that needs to be protected by a thermal barrier the same way as urethane foam needs to be protected.

Are there any alternative methods available?

Yes. The building code provides different options for achieving a 15 minute thermal break to keep ignition sources away from rigid, urethane and polystyrene foam plastics (plywood, gypsum board, etc). Be careful of thermal and intumescent paints which have not been tested or approved for use in Canada. There are no paints to date that meet the criteria for providing a 15 minute thermal barrier over rigid, urethane and polystyrene foam plastics as per the Ontario Building Code.

What fire rating is Monokote Z-3306?

The fire rating is between 10 to 15 minutes depending on application thickness according to CAN4-S124-M testing and classification.

What fire rating is Monokote MK6?

Depending on application thickness and design specifications a rating of up to four hours can be achieved.

Can I paint fireproofing?

Where desired, the natural sprayed texture of Z-3306 can be lightly trowelled to form a semi-smooth, paintable surface. A thin (nominal 1/16th inch) latex stucco overspray may be applied to form a hard eggshell finish, capable of withstanding significant physical contact and surface abrasion.