Wonder walls: 13 choices for the building envelope

BD+C editors present a roundup of the latest technologies and applications in exterior wall systems, from a tapered metal wall installation in Oklahoma to a textured precast concrete solution in North Carolina. 

1. LOW-INCOME HOUSING REVITALIZED WITH WEATHER-RESISTANT FAÇADE

The senior citizens and disabled individuals who live in Paul F. Cullum Tower, owned by the North Bergen, N.J., Housing Authority, now have a more colorful and energy-efficient home. A recent exterior retrofit designed by architect Lothrop Associates included ~117,000 sf of Alucobond aluminum composite material in nine colors, including eight Spectra colors that change depending on the viewing angle. The material includes two sheets of aluminum thermobonded to a plastic core in a standard 4mm thickness.

Previously, the façade had consisted of blue and white aluminum curtain wall with exposed gray concrete columns, conveying a utilitarian feel. General contractor Arco Construction installed the Alucobond panels after cleaning the curtain wall, repairing the concrete, and adding a vapor-permeable air barrier membrane. Three colors of granite stone veneer panels were also installed in varied heights on the first through fourth floors, mimicking the low-rise homes surrounding the project. 3A Composites USA

2. ARMY SELECTS PRECAST PANELS FOR VIRGINIA COMMAND HEADQUARTERS

Slenderwall—which combines a precast exterior panel with an integrated perimeter stud-wall system—was selected as a composite solution by the U.S. Army Corps of Engineers for the Army Command Headquarters at Fort Belvoir, Va. A design-build team including Perkins+Will and BRCA (architects) and Suffolk Construction (GC) created the four-story legal office building and courtroom on a fast-track schedule, winning the Associated General Contractors’ first-ever Best Lean Construction award. The Slenderwall panels’ thin-set brick finish echoes the look of nearby buildings, and a spray-applied interior coat of R-21 closed-cell foam insulation provides a continuous thermal, air, and moisture barrier. The hybrid system facilitated a compact construction schedule and helped increase energy efficiency for the LEED Gold project. Smith-Midland

3. NONCOMBUSTIBLE INSULATED PANELS CAN BE ERECTED IN A SINGLE STEP

Designed for noncombustible wall construction, new ThermalSafe NC insulated metal panels consist of a three-inch structural mineral wool core with R-11 thermal resistance, bonded to steel facings. The panels can be erected in one step with one crew, and are suitable for both exterior and interior walls. One-, two-, and three-hour fire-resistance ratings are available, with the LockGuard interlocking side joint enhancing resistance through a tongue-and-groove engagement of the mineral wool core. If a vapor seal is not required, sealant in the side joint may be omitted for faster installation of interior walls. The system includes lengths from 8 to 40 feet, with a module width of 42 inches. Metl-Span

4. CLEAR LABELING SIMPLIFIES SELECTION OF ARCHITECTURAL EPS INSULATION

Foam-Control Plus+ architectural-grade EPS insulation now provides face labeling showing UL certification information, ASTM type, compressive strength, R-value, product name, and termite-resistance characteristics. A first in the insulation industry, the face labeling makes it easier to compare the EPS (expanded polystyrene) product with XPS (extruded polystyrene) products. Available in R-values ranging from 5 to 30, Foam-Control Plus+ comes pre-scored and contains no dyes. Compressive strengths of 15, 24, 40, and 60 psi are available, and the product carries a 50-year warranty for R-value. ACH Foam Technologies

5. HIGH-PERFORMANCE CLADDING COMBINES ENERY EFFICIENCY AND IMPACT RESISTANCE

Outsulation X is a high-performance cladding system that yields 39% greater energy efficiency and 36% better impact resistance than similar EPS-based systems with comparable-weight reinforcing mesh, according to the manufacturer. The system incorporates two inches of Dow XNERGY rigid insulation and meets current and proposed ASHRAE design standards and IgCC/IECC code requirements for the use of exterior continuous insulation. Outsulation X provides a continuous layer of insulation, eliminating thermal breaks and moderating the temperature of the wall cavity, which reduces the potential for condensation. The product was designed as a single-source solution combining an air- and water-resistive barrier, exterior continuous insulation, and finished exterior wall. Dryvit

6. NORTH CAROLINA CHURCH CHOOSES TEXTURED PRECAST CONCRETE SOLUTION

Members of Triad Christian Fellowship Church in Winston-Salem, N.C., were seeking a traditional look combined with durability and energy efficiency as they planned their new sanctuary building. The congregation worked with Superior Walls of North Carolina to select the precast concrete Above Grade (AG) Wall System with a traditional red brick textured finish. The embossed panels, comprising 880 lineal feet of wall systems, were installed in just 14 hours to provide an insulated structural shell, ready for the installation of a roof system and interior slab. Superior Walls

7. ELECTRIC CAR BATTERY PLANT FEATURES INSULATED METAL PANEL SYSTEM

LG Chem’s new 650,000-sf plant in Holland, Mich., manufactures advanced batteries for the Chevy Volt, a hybrid electric-gas vehicle. Architects from Rosetti visited the Kingspan facility near Toronto before choosing the Optimo Smooth line of insulated metal panels for the façade. The system has tested R-values as high as 30, low thermal bridging, and superior air tightness, according to the manufacturer. Using a single-component façade reduced installation time by as much as 50%, and plant operation was able to begin three months ahead of schedule. The light and dark gray panels were also used for interior walls in the warehouse area. Also on the Building Team: Ghafari Associates (engineer), Roncelli Inc. (design-build contractor), and Universal Walls (façade installer). Kingspan

8. FAÇADE RENOVATION FIXES LEAKS WHILE ENHANCING RESORT’S APPEAL

A recent renovation of Silver Creek Resort, Snowshoe, W. Va., included a new EIFS to replace the previous material, which had not held up well in the area’s extreme climate. The Building Team of Peter Fillat Architects, Pillar Construction (GC), Keast and Hood (SE), and Williamson & Associates (envelope consultants) selected StoTherm Lotusan NExT, which includes a fluid-applied waterproofing air barrier, a finish with self-cleaning properties, and five inches of continuous insulation (~R-19). The renovation of the nine-story building required 125,000 sf of the product, as well as 740 new high-efficiency window assemblies. The envelope consultant conducted post-installation static pressure testing using ASTM E1105, which verified the façade’s performance. Sto Corp.

9. POLYISOCYANURATE WALLBOARD PRODUCTS IMPROVED FOR CONTINUOUS INSULATION

Atlas’s new EnergyShield Pro and EnergyShield PRO2 wall products reflect the commercial building industry’s new focus on continuous insulation for exterior walls, with an eye to long-term thermal performance. EnergyShield PRO consists of a Class A fire-rated closed-cell polyiso foam core, laminated between Class A durable aluminum facers. It combines rigid insulation board, high R value, and water-resistive barrier attributes with an acrylic-coated front facer and a reflective back facer. EnergyShield PRO2 is a Class 2 product, adding a glass-reinforced polyiso foam core to the features of EnergyShield PRO. The products are suitable for most vertical, above-grade wall applications, including wood frame, steel frame, concrete, CMU, and brick walls, according to the manufacturer. Atlas Wall CI Board

10. COMMERCIAL INSULATED SHEATHING SUITS HIGH-PERFORMANCE ENVELOPES

Roxul Comfortboard CIS is a rigid, high-density, noncombustible stone wool insulation board designed for use as an exterior continuous insulation in commercial rainscreen wall systems. Thermally efficient and vapor permeable, the new product pairs well with lightweight metal and composite panel systems, according to the manufacturer. Stone wool is also water-repellent, providing a tertiary drainage plane for water that migrates into the wall cavity while allowing the breathability necessary for outward drying. Comfortboard CIS is available in five thicknesses ranging from one to three inches, with insulation values of R-4 through R-12. Roxul

11. FIBER CEMENT PANELS COMPLETE MIXED-USE PROJECT AT HARVARD

For 1075 Mass Avenue, a new mixed-use project at the heart of the Harvard University community in Cambridge, Mass., Peter Quinn Architects specified the Illumination Series of fiber cement panels to create an upscale exterior look. Nichiha’s Color Xpressions system allowed the designer to create three customized colors. The panels offer the benefit of a built-in rainscreen system and concealed fastener system. The lightweight, fire-resistant cladding materials also made a winter installation possible for the Building Team. Nichiha USA

12. JOINT FLASHING ADDS WEATHER-TIGHTNESS TO FIBER CEMENT LAP SIDING PRODUCT

Bear Skin joint flashing is designed to work with CertainTeed’s WeatherBoards fiber cement lap siding, preventing water and wind-driven rain from infiltrating the butt joints. The new product is available in seven colors custom-matched to WeatherBoards ColorMax shades, helping to make vertical joints imperceptible. Installers can peel the material from a precut sheet and align the repositionable adhesive strip with joint gaps, according to the manufacturer. The flashing carries a 20-year UV rating and can withstand temperatures from -40°F to 180°F. WeatherBoards have a Class A flame-spread rating and are impact-resistant, UV-resistant, and impervious to wood-boring insects, according to the manufacturer. CertainTeed

13. TAPERED METAL PANELS ADD CULTURAL DIMENSION TO CHICKASAW NATION HEALTH CLINIC

The new 53,000-sf Chickasaw Nation Health Clinic in Tishomingo, Okla., replaced an outdated facility that was only a quarter as large. James R. Childers Architect selected Dri-Design Tapered Series aluminum panels as part of the façade, choosing a textured pattern and dark color to create a surface inspired by the culturally important Chickasaw blackberry. Panels were installed by NOW Specialties, using a manufacturer-supplied panel grid that established the desired pattern. The panels mark the main entrance as well as prominent stair towers at both ends of the building. The recyclable panels are designed for resilience and pass AAMA 508-07 rainscreen and Miami–Dade County hurricane-resistance standards. Dri-Design