FIRM-FILL® Frequently Asked Questions

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Choosing the Right FIRM-FILL® Product: A comprehensive list designed to help decide which FIRM FILL® product is right for the job.

FIRM-FILL® Gypsum Concrete underlayment: Premier underlayment designed for use in multi-family housing for sound and fire ratings.

FIRM-FILL® 2010 Underlayment: This underlayment provides the additional surface hardness and higher compressive strength needed for custom homes and condominiums.

FIRM-FILL® 3310 Underlayment: Use this underlayment when an exceptionally smooth, rock-solid surface is required in multi-family, single family or commercial construction.

FIRM-FILL® High Strength Underlayment: Our specially formulated underlayment for topping or resurfacing concrete floors and planks.

FIRM-FILL® 4010 Underlayment: An underlayment offering superior bonding capabilities for thin capping of concrete floors.

GYP-SPAN® Radiant Underlayment: This underlayment is designed for use over heating cables or hydronic systems; enhanced thermal mass and heat transfer.

Hacker TopCoat™ SP (Surface Prep): An acrylic based, film-forming surface preparation agent designed to meet ASTM F2419-05 compliance requirements for use on Thick Poured Gypsum Concrete Underlayments.

TRUE-SCREED® Cementitious Leveling Underlayment: Portland cement-based underlayment specifically designed for projects with deep-fill requirements that need to stay on budget.

DYNA-SCREED® SLU: This newest and most innovative Self Leveling Underlayment is the perfect solution for thin-capping concrete on fast-track renovation projects with demanding schedules.

The Following Documents Require the Adobe Acrobat Reader:

Gypsum Concrete Spec Sheet

Guidelines for Finishing Floors

Drying Conditions