Lathing Construction in USA: Comprehensive Guide to Traditional and Modern Methods

Understanding Lathing in American Construction

Lathing is a foundational component of both historical and modern construction methods in the United States. As professionals committed to excellence, we recognize that lathing construction is critical in creating a stable substrate for plaster, stucco, veneers, and even concrete bonding applications. This guide explores the different types of lath systems, their applications, installation methods, and how they contribute to residential, commercial, and restoration construction projects across the country.

Types of Lath Materials in the U.S. Construction Industry

1. Wood Lath

Wood lath is a traditional lathing material composed of thin wooden slats, usually ¼ inch thick, spaced approximately ⅜ inch apart. Common in buildings erected before 1940, it forms the basis for three-coat plaster applications.

Key characteristics:

• Typically pine, fir, or poplar
• Installed horizontally over studs
• Serves as a grip point for plaster “keys” that harden behind the lath

This method is still utilized today in historic renovations and custom heritage restorations where architectural authenticity is paramount.

2. Metal Lath

Metal lath has largely replaced wood in modern lathing due to its durability, fire resistance, and resilience to moisture. It is used in both interior and exterior applications, particularly as a base for stucco, veneer plaster, and EIFS (Exterior Insulation and Finish Systems).

Variants include:

• Expanded metal lath: A sheet of steel cut and stretched into a mesh
• Woven wire lath: Interlaced wire, ideal for lightweight assemblies
• Self-furring lath: Built-in dimples for space between sheathing and lath, eliminating the need for wood strips

Lath Accessories and Fastening Systems

Furring Strips

Furring strips provide the necessary space between the substrate and the lath to ensure proper plaster key formation and air circulation. In older homes, these strips were made of wood, but modern applications favor galvanized metal channels or plastic spacers.

Fasteners

Correct fastener selection is critical. We use:

• Galvanized nails or stainless-steel screws to secure lath to wood or metal framing
• Staples for attaching lath to plywood or oriented strand board (OSB)
• Tie wires in suspended ceilings or over masonry

Proper spacing—typically 6 inches on center along studs and every 7 inches along furring strips—ensures structural soundness and uniform adhesion of plaster or stucco.

Applications of Lathing in Various Construction Segments

Residential Construction

In U.S. homes, lathing is often employed for:

• Interior plaster walls
• Stucco exteriors
• Arched ceilings and curved surfaces

Traditional wood lath is now more common in restorative construction, while metal lath dominates new builds. Blueboard with veneer plaster is an effective modern alternative, offering the aesthetic of plaster with simplified installation.

Commercial Construction

Lathing plays a vital role in:

• Fire-rated assemblies
• Acoustic wall systems
• Architectural stucco facades

High-traffic commercial spaces demand durable and code-compliant systems, making galvanized metal lath the industry standard. Additionally, we implement corner beads, control joints, and plaster stops for sharp detailing and crack control.

Historic Restoration

For structures on the National Register of Historic Places, authenticity is crucial. We meticulously recreate original lathing systems, often sourcing reclaimed wood lath or replicating traditional techniques with modern safety improvements.

Three-Coat Plaster System Over Lath

When plastering over lath, the three-coat system remains the gold standard in traditional construction:

Scratch Coat

• First coat, ⅜-inch thick
• Applied directly to lath
• Scored to provide grip for the next coat

Brown Coat

• Provides mass and strength
• Levels and trues the wall surface
• Usually ¼ to ⅜-inch thick

Finish Coat

• Final layer, typically ⅛ inch
• Composed of lime, gauging plaster, or veneer
• Smoothed or textured depending on design specifications

This system yields a hard, durable surface that resists impact, fire, and sound transmission far better than conventional drywall.

Modern Innovations in Lathing Systems

Pre-Fabricated Lath Panels

Pre-welded lath panels have emerged as a time-saving innovation. These modular lath sheets improve speed, reduce waste, and ensure uniformity across large surfaces.

Synthetic Lath (Plastic Lath)

Plastic lath systems, typically made from high-density polyethylene (HDPE), are corrosion-proof and ideal for salt-air climates, such as coastal Florida or California. These systems meet ASTM and ICC requirements and are gaining traction in moisture-sensitive applications.

Moisture Barriers and Sheathing Compatibility

Behind any exterior lath, a proper moisture barrier is essential. We typically install:

• Grade D building paper
• House wrap (e.g., Tyvek StuccoWrap)
• Liquid-applied membranes

Additionally, compatible sheathing materials such as plywood, OSB, or gypsum board must be used, with an emphasis on ventilation, water shedding, and load distribution.

Fire Resistance and Code Compliance

Lath and plaster assemblies offer natural fire resistance due to their non-combustible ingredients. In commercial construction, these assemblies contribute to UL-rated wall systems meeting ASTM E119 fire testing standards. Fire-rated plaster assemblies include:

• Metal lath secured over type X gypsum board
• Plaster applied in layers totaling ⅞ inch
• Approved edge reinforcement systems

Acoustic and Thermal Performance

A properly constructed lath and plaster wall achieves excellent sound transmission class (STC) ratings, often exceeding STC 55, making it ideal for:

• Music studios
• Theaters
• Luxury condominiums

Additionally, these walls retain thermal mass, improving temperature regulation and contributing to energy-efficient designs.

Common Tools in Lathing Construction

Executing quality lathing demands specific tools, including:

• Plaster hawks
• Margin and pool trowels
• Scratch rakes
• Tin snips for cutting metal lath
• Leveling screeds
• Power drills and staplers

Craftsmanship is as critical as tools. Our trained plasterers ensure flat, durable surfaces capable of standing for generations.

Inspection and Quality Assurance

Lathing construction is subject to strict building code inspection protocols. Key checkpoints include:

• Lath fastening spacing
• Moisture barrier integrity
• Overlap of joints and seams
• Control joint placement
• Proper embedment of accessories

We work closely with local inspectors and engineers to guarantee code compliance, structural integrity, and project longevity.

Conclusion

Lathing construction in the USA remains a cornerstone of both legacy and modern building systems. From classic wood lath in historic homes to engineered metal lath systems in commercial towers, the discipline has evolved while preserving its core principles. Every nail, joint, and trowel pass contributes to the durability, beauty, and fire-resistant quality of the final structure.

As experts in lathing construction, we continue to deliver projects that honor time-tested practices while incorporating today’s best innovations.