Fiberlock TBC Encasement Coating for Exterior Transite

Fiberlock TBC: the coating that encapsulates exterior asbestos cement

FIBERLOCK manufacturer code: 6497-White

TBC (Transite Barrier Compound) is an encasement coating designed for asbestos-containing fibre cement panels (transite) outdoors: siding, roofing and cladding. Instead of removing the panels, they are covered with a thick, hard and flexible film that resists UV and mildew. The high solids water-based formula is ready to use and must not be diluted. TBC goes on transite primed with a Fiberlock surface conditioner, and the treated surface must be inspected regularly.

If the transite is aged and friable, first apply Fiberlock Grip-Tack (SAH64085) lockdown adhesive to stabilize the surface before TBC.

Characteristics of TBC coating for asbestos cement

• High solids water-based thermoplastic elastomeric copolymer (59% by weight, 45% by volume)
• Hard, flexible finish that resists UV and mildew
• White, flat finish
• Meets ASTM E-1795, certified for use in all 50 states, compliant with federal and state VOC requirements (88 g/L)
• 5 gal US (18.9 L) pail

TBC coating applications on exterior transite

Ready to use: Do not dilute, thin or mix with any other product. For encapsulating transite outdoors. Coverage: 50 to 100 sq ft/gal depending on the porosity of the transite and the target thickness.

How to apply TBC on asbestos cement

1. Check the regulations (work practices, personal protection) before surface preparation.
2. Inspect surfaces: clean, dry, free of dust, rust, grease, oil, mildew and peeling paint.
3. Prime all transite with a Fiberlock surface conditioner before TBC; if the transite is aged and friable, first apply a surface adhesive such as Grip-Tack.
4. Mix well: the clear liquid found on opening is part of the product and must be fully blended in.
5. Apply generously and evenly when air and surface are above 50 °F (10 °C), with no rain expected within 3 h of the last coat.
6. Apply several coats as needed for the desired dry thickness, letting each coat dry. EPA guidance: for a bridging encapsulant, no more than 100 sq ft/gal, a continuous film much thicker than paint.
7. Topcoat with paint if needed, for colour or appearance.
8. Clean tools and drips with warm soapy water before drying and dispose of waste according to regulations.
9. Inspect treated surfaces regularly; repair and reapply immediately if damaged.

TBC spray tools and settings

Brush, roller or airless sprayer set at 2500 to 3000 psi, with a .019 to .021 in tip and a minimum output of 0.50 gal/min.

Dry to the touch in 1 to 2 h, recoatable in 8 to 16 h and fully cured in 12 to 24 days at 70 to 77 °F and 50% relative humidity.

TBC storage, care and inspection

Store in a dry place between 40 °F (4.5 °C) and 90 °F (32 °C), container tightly closed. In its sealed original container, TBC keeps for at least 24 months. Periodic inspection of treated surfaces is mandatory: repair and reapply promptly if damaged.

Safety and protection during asbestos cement encapsulation

The safety data sheet carries the signal word WARNING and classifies the product as a category 2 carcinogen (IARC group 2B, by inhalation). While spraying, wear a NIOSH respirator with an R, P, N or HE filter and protective clothing. Follow the regulations in force for asbestos work.

Fiberlock TBC coating FAQ

Can TBC be diluted?

No. TBC is ready to use: do not dilute, thin or mix it with any other product.

Is a primer needed?

Yes. All transite is primed with a Fiberlock surface conditioner before TBC. If the transite is aged and friable, a surface adhesive such as Grip-Tack goes on first.

How much area does one gallon cover?

50 to 100 sq ft/gal depending on the porosity of the transite and the target thickness. For a bridging encapsulant, EPA guidance recommends no more than 100 sq ft/gal.

What weather conditions are needed?

Air and surface must be above 50 °F (10 °C), with no rain expected within 3 h of the last coat.

Can TBC be painted over?

Yes, TBC can be topcoated with paint for colour or appearance.

Complementary suggestions for asbestos cement encapsulation

For the roofer or contractor treating exterior asbestos cement siding: a 3M 6000 series full face mask (R6800), 3M 7093 P100 filters (R7093), a white type 5 hooded disposable coverall (V51), 13 in nitrile gloves (GL9315), 3M OX safety eyewear (YA12166) and Tyvek all-purpose boot covers (VC1453).

To prepare the surface and run the site: an 8 L pump sprayer (SACC2) to wet the transite, a 6 mil white polyethylene roll (SACCT4) to protect the ground, white tape (SATW), a HazVac industrial vacuum (SAD5) for cleanup and the statutory asbestos site sign (EAMIANTE).

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