Mesa-Lok

Mesa-Lok is the lined-profile PAC-CLAD insulated metal panel for commercial and industrial buildings. The face carries a shallow Mesa rib, and the lines in the profile add strength, aid foam adhesion and reduce the visibility of natural imperfections in the steel faces.

It differs from Mesa-Lok HSE in its formed face and joint, since the HSE variation adds a heavy stucco embossment.

Mesa-Lok is listed for four uses: exterior wall, partition wall, liner wall and ceiling. Of the wall panels in its group it has the widest list of uses and the widest range of exterior finishes.

• Coverage width: 42 inches.
• Available thicknesses: 2, 2.5, 3, 4, 5 and 6 inches.
• Lengths of 8 feet 0 inches up to 53 feet 0 inches are made.
• Exterior gauge: 26, 24 or 22. Interior gauge: 26.
• Nominal R-value: R-8 per inch of thickness.

The exterior substrate can be Galvalume, G90 galvanized steel or stainless steel, and the interior substrate has the same three options.

Exterior finishes are polyester, siliconized polyester, low-gloss PVDF and plastisol (PVC). Interior finishes are polyester, siliconized polyester and plastisol (PVC). Both faces come embossed or smooth.

An offset double tongue-and-groove joint, trade-named Green-Lock, joins the panels. The shallow Mesa rib and the side joint are designed for a vapor seal. The core is polyisocyanurate foam poured in place continuously.

The core shows 16 psi shear strength (ASTM C273), 18 psi compressive strength (ASTM D1621), a density of 2.25 pcf (ASTM D1622) and 21 psi tensile strength (ASTM D1623). At least 90% of the cells are closed (ASTM D6226).

The K-factor under ASTM C518 is 0.139 Btu-in/hr-ft2-F at a 75 F mean temperature and 0.129 at a 35 F mean temperature. Air leakage is 0.0011 cfm/sf at 20 psf (ASTM E283), and no water penetrates at 20 psf (ASTM E331).

Flame spread is under 25 and smoke developed under 450 in ASTM E84. NFPA 285 is recorded as passed, FM 4880 as Class 1 fire rated and FM 4881 as a Class 1 approved exterior wall system.

Impact follows TAS 201 with Miami Dade County NOA No. 20-1202.02. Florida Product Approval 16327.1 R3 and Texas Department of Insurance Evaluation ID EC-103 are also named. FM 4881 very severe hail resistance is part of the guide specification.

Positive and negative load resistance comes from ASTM E1592 or ASTM E72 tests, and loads are calculated to ASCE 7-16. Deflection is limited to L/180 or the code limit, whichever is greater, and the panel factor of safety is 2.0. The delivered steel thickness must be within 95% of the design thickness.

Panels arrive in shrink-wrapped, weather-resistant packaging. Bundles are stored level with one end raised for runoff and are stacked no more than two high. Strippable film is removed during or just after installation and kept out of direct sunlight for no more than 24 hours.

Mesa-Lok is the most widely used and accepted panel in the range. Its exterior and interior substrates can each be Galvalume, stainless steel or G90 galvanized steel, and both faces come in an embossed or smooth texture.

• Publishes a wall uniform load table and clip load tables for BAC-08 and BAC-12.
• A partition span table is published for Mesa-Lok.
• FM approvals: 4880, 4881, 4881 BAC-08, 4881 Back Fastened.
• Bulletins: infiltration, flame spread, K-factor, NFPA 285, weights, R-values.

Mesa-Lok drawings span horizontal and vertical open framing, with door header, door jamb, corner, side joint, sill and window details. The vertical set also holds a stack joint detail.

Mesa-Lok shares its name with the heavy stucco Mesa-Lok HSE, one of seven profiles in the range. Carlisle Construction Materials, part of Carlisle Corporation, owns the brand.