What Is Expanded Metal Lath? (Simple Definition)

What is expanded metal lath? Expanded metal lath is a lightweight, rigid, diamond-patterned metal sheet made by slitting and stretching solid metal (usually galvanized steel or stainless steel) into an open mesh structure. It is a specialized construction reinforcement material designed to support plaster, stucco, mortar, and concrete coatings.

Unlike welded wire mesh or fiberglass mesh, expanded metal lath is made from a single piece of metal – no welds, joints, or breaks. This monolithic structure gives it exceptional strength, bonding ability, and durability for interior and exterior construction applications.

Also known as metal lath, stucco lath, or plaster lath, this product is the industry standard for reinforcing wall and ceiling finishes. Our expanded galvanized metal lath is the most widely used type in residential, commercial, and industrial construction globally.

How Is Expanded Metal Lath Made? (Manufacturing Process)

Understanding **what is expanded metal lath** requires knowing how it’s manufactured. The expanded metal lath production process is precise, efficient, and creates a strong, consistent product without waste.

1. Raw Material Preparation: High-quality galvanized steel or stainless steel coils are loaded into automated expanding machines
2. Slitting & Stretching: A specialized die cuts and stretches the metal sheet simultaneously, creating uniform diamond openings
3. Forming: The expanded metal is flattened or self-furred (dimpled) for specific construction uses
4. Cutting & Shearing: The expanded metal is cut into standard sheet or roll sizes
5. Surface Treatment: Additional galvanizing or passivation ensures corrosion resistance
6. Packaging: Finished lath is bundled and packaged for shipping worldwide

The entire process uses 100% of the raw metal – no scrap is generated, making expanded metal lath an eco-friendly construction material. Our advanced metal mesh manufacturing lines produce lath with consistent diamond size, thickness, and strength for reliable performance on every job.

What Materials Is Expanded Metal Lath Made Of?

Expanded metal lath is manufactured from high-performance metals selected for strength, corrosion resistance, and workability. The material directly impacts its durability, application, and lifespan.

Galvanized steel is the most popular choice due to its unbeatable balance of cost and performance. Stainless steel lath is used in demanding environments where rust prevention is critical. We never use low-quality or recycled metals that compromise strength or durability.

Main Types of Expanded Metal Lath

Now that you know **what is expanded metal lath**, it’s important to understand the different types available. Each type is engineered for specific installation conditions and performance needs.

1. Standard Flat Expanded Metal Lath

The most common type, with a flat, smooth surface and uniform diamond openings. Used for standard plaster and stucco applications on wood, metal studs, and flat surfaces. Easy to cut, bend, and install for general construction projects.

2. Self-Furred Expanded Metal Lath

Features small raised dimples across the surface that create a 1/8-inch gap between the lath and the wall. This gap allows plaster or mortar to fully encapsulate the lath, creating a mechanical bond that prevents delamination. Ideal for masonry, concrete, and uneven surfaces.

3. Corner Lath & Angle Bead

Pre-formed V-shaped lath designed to reinforce external wall corners, doorways, and window openings. Creates sharp, straight, durable corners that resist chipping, cracking, and impact damage. Essential for professional-quality finishes.

4. Ribbed Lath (HY-Rib)

A heavy-duty reinforced lath with longitudinal ribs for extra strength. Used for high-stress applications, large wall surfaces, and concrete slab reinforcement. Our HY-Rib expanded metal sheet is the premium choice for structural reinforcement.

Key Specifications & Dimensions

Expanded metal lath follows strict international standards for size, thickness, and diamond pattern. These specifications ensure compatibility with construction codes and installation practices worldwide.

• Standard Sheet Size: 27” x 96” (2.25ft x 8ft) – the most common size
• Roll Size: 27” width x 50’ length – for large surface areas
• Standard Thickness: 0.018” to 0.039” (28ga to 18ga)
• Diamond Opening Size: 3/8” x 1” (standard stucco/plaster pattern)
• Weight: 2.5 lbs to 3.5 lbs per sheet (galvanized)
• Surface Treatment: Hot-dip galvanized (ASTM A653)

All our expanded metal lath products comply with ASTM C847 – the international standard for metal lath used in plaster and stucco construction. This certification ensures your project meets building codes and inspection requirements.

What Is Expanded Metal Lath Used For?

Expanded metal lath is a versatile construction material with a wide range of essential uses. Its primary purpose is reinforcement, but it supports many different finishes and applications.

• Reinforcement base for exterior stucco and EIFS systems
• Interior plaster, gypsum veneer, and decorative wall finishes
• Concrete and masonry repair and overlay reinforcement
• Fireproofing coating support for structural steel members
• Tile backer support in bathrooms, kitchens, and wet areas
• Stone veneer and thin brick installation base
• Curved wall, arch, and column plaster reinforcement
• Historic building restoration and plaster conservation

No other construction mesh offers the same combination of strength, bonding, flexibility, and durability as expanded metal lath. It is irreplaceable for professional plaster and stucco installations.

Top Benefits of Expanded Metal Lath

The unique design and construction of expanded metal lath provide unmatched advantages over alternative materials like paper lath, fiberglass mesh, or welded wire mesh.

• Superior Bonding: Diamond pattern mechanically locks in plaster and stucco
• Crack Prevention: Distributes stress to eliminate finish cracking
• Monolithic Strength: No welds = no weak points or breakage
• Fire Resistance: Non-combustible metal enhances building safety
• Corrosion Resistance: Galvanized/stainless steel resists rust and decay
• Flexibility: Conforms to flat, curved, and irregular surfaces
• Long Lifespan: Lasts 50+ years with minimal maintenance
• Cost Effective: Reduces repair and replacement costs over time

These benefits explain why expanded metal lath has been the construction industry standard for over a century and remains the top choice for professional contractors and architects today.

Installation Basics for Expanded Metal Lath

While professional installation is recommended, understanding the basics helps you appreciate **what is expanded metal lath** and how it performs in real-world construction.

• Attach lath to studs or masonry with corrosion-resistant fasteners
• Overlap sheets by 1–2 inches to create a continuous surface
• Install horizontally with diamond openings facing upward
• Use corner lath for all external 90-degree angles
• Apply a scratch coat of mortar immediately after installation
• Ensure lath is tight and secure with no loose areas

Proper installation ensures the lath performs its critical reinforcing function, delivering a smooth, durable, and long-lasting finish for walls and ceilings.

Why Choose Our Expanded Metal Lath?

As a leading metal mesh manufacturing expert with 20 years of experience, ANPING METAL MESH produces the highest quality expanded metal lath on the global market. Our products are trusted by professionals in 50+ countries for their consistency, strength, and compliance with international standards.

• 20 years of specialized expanded metal lath production experience
• 100% premium raw materials – no low-grade or inferior metals
• ASTM C847 certified for global construction code compliance
• Complete product line: flat, self-furred, corner, ribbed, and stainless lath
• Automated production for consistent quality and dimensions
• Custom sizes and specifications available for unique projects
• Factory-direct pricing with fast, reliable worldwide shipping
• ISO 9001 quality management system certified

When you choose our expanded metal lath, you choose a product engineered for professional results. Our custom expanded metal service also allows us to create tailored lath solutions for your specific project requirements.