What is steel framing (LGS)? Complete guide

Light Gauge Steel (LGS), also called "steel framing," is a construction system based on cold-formed steel profiles (no welding) at 0.85–2.5 mm (0.033–0.098 in) thickness, typically used for low- and mid-rise structures: multifamily residential, educational buildings, clinics, shopping centers, and lightweight industrial structures. Unlike PEB (Pre-Engineered Buildings) systems that use welded beam-column profiles at 5+ mm (0.2+ in) thickness with 50+ metric ton load capacity, LGS is more economical, modular, and suited for distributed medium-range loads (typically 10–30 metric tons per frame). Within the PEB Corp Group, NewCon Steel® manufactures the LGS members and PEB Corp provides the engineering, to AISI S100 (American Iron and Steel Institute) and ASTM C955 (steel stud wall systems).

Material specifications—0.85–2.5 mm thicknesses, Zn-Al-Mg 275 g/m² coating (ZM275), and ±0.5 mm tolerance—are published by the group's manufacturer on the NewCon Steel® LGS/CFS profiles page. Codes and reference prices for this market are on our Panama page.

What is steel framing? Key differences from heavy PEB

Steel framing is cold-formed steel: C, G (Sigma), Z, and Omega profiles at 0.85–2.5 mm (0.033–0.098 in) thickness, fastened with self-drilling screws or structural rivets. Load capacity is achieved by member integration with lateral bracing panels, concrete floor slabs, or steel deck. Applications: mid-rise multifamily residential in land-scarce urban areas where density is critical; hospitals/clinics where floor-by-floor occupancy during construction accelerates revenue; schools where load predictability and $/m² economy are central.

Critical difference versus PEB (industrial warehouses): PEB uses welded H/I profiles (10+ mm / 0.4+ in), supports enormous concentrated loads (cranes, 50+ metric ton lifts), designed for 20–50+ meter (65–164+ ft) clear spans without intermediate supports. LGS uses slender C/G profiles, designed for 5–12 meter (16–39 ft) beams with close column spacing (3–5 m / 10–16 ft), and distributed loads typically 300–500 kg/m² (60–100 psf). The cost of each system is quoted per project: in LGS, profiles are smaller and joined with screws.

Zn-Al-Mg 275 g/m² coating and corrosion protection

NewCon Steel fabricates LGS profiles with Zn-Al-Mg 275 g/m² coating (275 g/m² / 0.9 oz/ft² zinc-aluminum-magnesium alloy). This coating offers higher corrosion resistance than conventional galvanizing in tropical environments. Advantage in Panama/Colombia: no paint required if project is in non-saline zones (interior). In coastal or extreme-humidity zones, an epoxy primer and polyurethane finish are added, at extra cost. The coating mass is not a service-life guarantee; warranty terms are defined in each project contract.

Coating comparison: unprotected steel = visible rust in 6 months tropical climate; conventional galvanizing = consumed faster on the coast; Zn-Al-Mg 275 g/m² = greater durability with minimal maintenance. Cost differential: Zn-Al-Mg 275 g/m² costs somewhat more than conventional galvanizing, which is justified by its durability in a tropical context.

Design standards: AISI S100 and ASTM C955

AISI S100-16 (R2020) (North American Specification for the Design of Cold-Formed Steel Structural Members) is the de facto standard in Panama, Colombia, and the Caribbean for LGS. Defines calculation procedures for compression, flexure, shear, and connections in cold-formed steel. ASTM C955-20 specifies material and fabrication requirements for steel stud wall systems, including alignment tolerances and minimum thickness by application (e.g., 89 mm × 42 mm × 1.2 mm / 3.5×1.65×0.05 in studs for non-load-bearing walls).

PEB Corp designs LGS members to AISI S100-16 (R2020), with the load combinations of the local code. Seismic compliance: REP-2021 (Panama), NSR-10 (Colombia). Requires explicit design of bracing systems (diagonals, shear panels) for site spectral acceleration, typically 0.25–0.35g in the region.

Residential applications: mid-rise multifamily

LGS is standard solution in cities with mid-density housing demand: San Miguelito, Panama Viejo, Coronado (Panama); Bogotá north, Medellín, Cali (Colombia); Barbados, Trinidad (Caribbean). Typology: 5-story building, 60 m² (645 ft²) per unit, 12 units/floor = 3,600 m² (38,750 ft²) total. LGS structure: C150×65×2.0 mm columns (150 mm / 5.9 in height, 65 mm / 2.6 in flange, 2.0 mm / 0.08 in thickness) spaced 3 m (10 ft), G300×2.0 mm beams (300 mm / 11.8 in height) at 1.2 m (4 ft) spacing, 100 mm (4 in) reinforced concrete floor slab on beams. Structure cost: quoted per project. Schedule: 18–24 weeks total, shorter than masonry/concrete. Operational advantage: partial occupancy year 1 (3 floors operational) generates rental income while remaining floors under construction.

LGS advantages for residential: modularity allows plan changes without compromising capacity (non-load-bearing walls easily relocated); MEP installation precision (electrical, water lines pre-routed); elimination of damp-out periods typical of concrete curing (faster drying); 100% recyclability if project abandoned or redesigned (steel sold to scrap dealer).

Commercial applications: clinics, schools, and shopping centers

2,500 m² (26,910 ft²) clinic × 3 floors in Panama: LGS structure enables open layouts (12 m / 39 ft clear span) without interior columns interrupting clinic floorplan. Structure cost: quoted per project. Schedule: 20 weeks, shorter than reinforced concrete. Critical advantage: floor-by-floor occupancy. Ground floor (emergency + lab) operational in week 12; upper floors continue construction. Hospital captures early-stage revenues without waiting for project completion, improving ROI.

3,000 m² (32,292 ft²) school × 1 story in rural zone (classrooms, cafeteria, administration): LGS provides prefabricated modular classroom units (4m×6m / 13×20 ft per classroom, each a structural entity transportable). Advantage: parallel manufacturing (multiple classrooms fabricated simultaneously in plant, transported to site sequentially). Total time: 16 weeks, shorter than traditional construction. Cost: quoted per project. Durability: Zn-Al-Mg 275 g/m² offers higher corrosion resistance than conventional galvanizing, with reduced maintenance.

LGS versus timber framing: resistance, durability, and economics

Wood framing (3×8, 2×6 / 75×200 mm, 50×150 mm lumber) in coastal/tropical regions suffers: termite colonization (Reticulitermes, Coptotermes) without chemical protection (with costly replacements); humidity-induced rot (moisture levels post-occupancy accelerate decay); UV degradation in exterior exposure. A typical timber frame in Panama requires annual inspection and periodic chemical treatment, with a significant cumulative maintenance cost.

LGS: zero termite susceptibility (non-organic), zero rot risk (non-hygroscopic) and reduced maintenance in typical tropical climate when Zn-Al-Mg 275 g/m² is used. In a total cost of ownership analysis, LGS is competitive with timber once timber's accumulated maintenance is included; compare quotations with the same scope.

LGS versus concrete block: comparative economics

Concrete block (200×200×400 mm / 8×8×16 in, standard mortar) remains popular in low-income residential. Advantages: low material cost, local labor access, high thermal mass. Disadvantages: extended schedules (unit-by-unit laying), variable quality (poor joints allow infiltration), seismic vulnerability (REP-2021 requires additional reinforcement, which raises cost once proper horizontal/vertical reinforcement is included).

LGS versus block: both are quoted per project. LGS wins on time and tends to compete on net cost once the block's seismic reinforcement is included. LGS flexibility: post-occupancy reconfiguration by relocating studs (no demolition); block changes require full demolition, at additional cost.

Design-to-fabrication process: from BIM to screw assembly

PEB Corp Group workflow for LGS: (1) Client provides architectural drawings (AutoCAD/Revit), floor dimensions, operational loads. (2) Engineering calculates members per AISI S100, generates structural plans with full dimensions, component list (C studs, G beams, connections, fasteners, bracing). (3) CNC fabrication cuts profiles to tolerance (±0.5 mm / ±0.02 in), generates floor kits (floors 1, 2, 3 packaged separately with labels and assembly guide). (4) Transport and assembly: carried out by SmartBrix Construction or the contractor defined in the contract, with a crew of 8–12. (5) Commissioning: inspection, alignment, torque verification of fasteners.

Cost breakdown per m² for a typical project

Residential building 2,500 m² (26,910 ft²) × 4 floors (structure only):
Block + seismic reinforcement: quoted per project
Reinforced concrete: quoted per project
Steel framing LGS: quoted per project
LGS savings versus reinforced block or concrete: confirmed by comparing quotations with the same scope

Durability in a tropical environment: Zn-Al-Mg 275 g/m² versus standard galvanizing

Salt-spray testing (ASTM B117) compares coatings but does not predict service life linearly. In the field, Zn-Al-Mg 275 g/m² offers higher corrosion resistance than conventional galvanizing, especially in coastal zones. In non-saline interior locations the difference is smaller, but Zn-Al-Mg 275 g/m² provides an extra margin if the building ends up exposed to more humidity after construction (common in Panama when commercial tenants change use).

ISO certifications and code compliance

The ISO 9001:2015 certification belongs to the PEB Corp Group; NewCon Steel® is the group's manufacturing company, not a division of PEB Corp. Group structures are designed to REP-2021 (Panama), NSR-10 (Colombia), and IBC (Caribbean). Deliverables: sealed structural calculations by professional engineer, fabrication drawings, material certifications (steel composition, thickness). Warranty terms are defined in each project contract.