Comparing Butler MR-24 and Butlerib II Roof Systems - Performance, Specs, and Applications

Choosing the right roof system for a metal building is a important decision that considers durability, energy efficiency, maintenance, and long-term costs. Butler Manufacturing's two most popular roof systems, the MR-24 and the Butlerib II, are both iconic but are indeed designed to meet different needs. By understanding the insulation capabilities, performance characteristics, and ideal use cases for these systems, you can make an informed choice that ensures the success of your project.

Understanding the MR-24 Roof System

The MR-24 roof system stands out as the industry’s leading standing-seam metal roof system. Introduced in 1969, it has set the benchmark for durability, energy efficiency, and performance with over 2 billion square feet installed globally.

Key Benefits:

Superior Insulation: The MR-24 supports rigid board insulation (CMR-24) with R-values up to R-40. This makes it an excellent choice for buildings requiring enhanced thermal efficiency, such as climate-controlled warehouses, manufacturing facilities, and office buildings.
Performance Under Pressure: The system features a Pittsburgh double-lock seam, ensuring a watertight seal that prevents leaks even under heavy rainfall or snow. The seam is mechanically field-formed to create a monolithic surface, enhancing resistance to wind uplift and external forces.
Thermal Expansion Capability: Its unique floating clip system allows the roof to expand and contract with daily and seasonal temperature fluctuations. This prevents structural stress, reducing the likelihood of damage over time.
Sustainability: The MR-24 is made from recyclable materials and comes with optional "cool roof" finishes that reduce heat absorption. These features align with energy efficiency goals and can contribute to LEED® certification.

Ideal Use Cases:

The MR-24 is best suited for buildings where long-term performance and minimal maintenance are essential. It excels in environments with extreme weather conditions or temperature variations, such as:

Manufacturing plants
Distribution centers
Large retail stores
Airports and transportation hubs

These buildings benefit from the system’s high wind resistance, leak-proof design, and ability to maintain interior climate control efficiently.

Understanding the Butlerib II Roof System

The Butlerib II system is a through-fastened roof system known for its affordability and dependable performance. Designed to balance cost-efficiency with durability, it is widely used in projects with tighter budgets.

Key Benefits:

Economical Insulation: The Butlerib II accommodates blanket insulation, which is cost-effective and provides adequate thermal protection for buildings in less extreme climates. While it doesn’t achieve the same R-values as the MR-24, it remains a practical choice for many applications.
Durable Design: This system features 1.5-inch corrugations and factory-punched panels for accurate alignment during installation. These attributes make the roof durable enough to withstand regular foot traffic and routine maintenance.
Affordability: The Butlerib II system offers lower initial costs, making it an attractive option for budget-conscious projects. Despite its lower price point, it provides excellent weather resistance and reliability.
Warranty Protection: Backed by a 10-year weather-tightness warranty, the system gives building owners peace of mind at a fraction of the cost of higher-end options.

Ideal Use Cases:

The Butlerib II is an excellent choice for buildings where budget constraints are a primary concern, and extreme weather resistance or high thermal efficiency is not critical. Examples include:

Community centers
Storage facilities
Agricultural buildings
Churches and schools

These applications benefit from the system’s affordability and ease of installation without compromising on essential protection.

Comparing the MR-24 and Butlerib II Roof Systems

Feature	MR-24 Roof System	Butlerib II Roof System
Seam Type	Standing-seam, Pittsburgh double-lock	Through-fastened, corrugated
Insulation Options	Blanket or Rigid board, up to R-40	Blanket insulation, lower R-values
Thermal Expansion	Floating clip system for free movement	Factory-slotted holes for limited movement
Durability	Twice the lifespan of conventional roofs	10-year warranty, dependable for basic use
Cost	Higher initial cost, lower lifecycle cost	Lower initial cost, higher lifecycle costs

How to Choose the Right Roof System

When deciding between the MR-24 and Butlerib II, consider your building’s function, budget, and long-term goals.

Choose the MR-24 if:
- Energy efficiency is a priority.
- Your building will experience significant thermal expansion and contraction.
- You need a roof that withstands harsh weather conditions and provides decades of reliability.
Choose the Butlerib II if:
- You’re working within a tight budget.
- Your building doesn’t require advanced thermal protection.
- Simplicity and speed of installation are important.

Wrapping Up

Both the MR-24 and Butlerib II systems are excellent roofing solutions tailored to different needs. The MR-24 shines in performance, durability, and energy efficiency, while the Butlerib II offers affordability and reliability for less demanding applications. By carefully evaluating your project requirements, you can select the roofing system that delivers the best value for your investment.

For expert advice and access to high-quality Butler Manufacturing parts, reach out to us at Butler MFG Parts.