Blog / Mil Thickness Matters: Understanding Surface Protection for Construction

March 24, 2025

When it comes to protecting surfaces during construction or renovation projects, choosing the right type of paper can make all the difference. In this blog, we’ll explore the differences between red rosin paper, builders paper, X-Paper, X-Board, and FloorShell. We’ll highlight their mil thickness, range of applications, longevity, and why you might choose each one. This guide will help you make an informed decision for your next project.

WHAT IS MIL THICKNESS?

Mil thickness is a measurement used to describe the thickness of a material. One mil is equal to one-thousandth of an inch (0.001 inches). Understanding mil thickness is important when selecting paper and board products, as it may impact its durability and suitability for different applications.

BUILDERS PAPER VS. RED ROSIN PAPER

• Mil Thickness: Builders paper generally measures 7 mils, while red rosin paper can range from 7-8 mils.
• Applications: Both builders paper and red rosin paper are used for protecting surfaces during construction projects. Builders paper is ideal for covering large areas quickly and is often used in painting and staining projects. Red rosin paper, on the other hand, is commonly used as a protective barrier in flooring and roofing projects and as a separation layer to prevent dust.
• How to choose: We recommend utilizing either builder’s paper or red rosin paper for short-term construction projects. Both choices are cost-effective solutions for temporary surface protection, providing a small line of defense against damage. Red rosin paper is an excellent choice for temporary protection and as an underlayment in flooring and roofing projects.

HEAVY-DUTY SURFACE PROTECTION FOR CONSTRUCTION

Sometimes kraft paper just won’t cut it, and heavy-duty protection is needed on the job. Trimaco offers three different heavy-duty paper and board options that have a thicker mil thickness than traditional builder’s paper and red rosin paper:

X-PAPER

• Mil Thickness: 1.5X thicker than standard builders paper, typically around 12 mils.
• Applications: A step up from builder’s paper, X-Paper is designed for temporary floor protection. It’s breathable, tear resistant, and easy to work with on the job. X-Paper offers excellent durability for short to medium-term projects. The durable floor protection rolls offer excellent coverage for various surfaces, such as hardwood floors, stairs, cabinets, and countertops. X-Paper resists minor spills, allowing you to spend less time on application and reapplication.
• Why X-Paper: Love builder’s paper? We recommend giving X-Paper a shot. Choose X-Paper for its enhanced durability, breathability, and tear resistance. Spend less time reapplying builder’s paper, and more time on the job at hand.

X-BOARD

• Mil Thickness: 2.5X thicker than builder’s paper, roughly 20 mils.
• Applications: X-Board provides dependable surface protection for painting and remodeling jobs. It’s breathable and spill-resistant, making it ideal for protecting floors, hallways, and countertops from equipment and foot traffic. Because of its durability, it’s great for long-term use on the job.
• Why X-Board: Opt for X-Board when you need long-term, dependable protection for high-traffic areas and heavy-duty projects. Its thickness and durability make it a top choice for professional contractors and painters.

FLOORSHELL

• Mil Thickness: Around 40 mils.
• Applications: Got a tough job? FloorShell is designed for the most demanding projects. It provides superior protection for floors from heavy machinery and extensive foot traffic, that may need some impact resistance. FloorShell offers exceptional durability for long-term projects. It’s water-resistant and can handle even the toughest conditions.
• Why FloorShell: Choose FloorShell for your most demanding jobs. It’s the best option for large-scale projects where maximum surface protection is required.

Trimaco has you and your surfaces covered.

Choosing the right protective paper or board products is essential for achieving total jobsite protection. Whether you require the cost-effectiveness of builder’s paper, or the superior strength of FloorShell, understanding their unique qualities and mil thicknesses will help you select the best option for your project. Explore Trimaco’s full line of heavy-duty surface protectors, or use our surface protection selector for more assistance!