Introduction
Wall pack lights are ubiquitous in the landscape of commercial and industrial architecture. Mounted on the exterior walls of buildings, these fixtures provide essential security, safety, and aesthetic illumination for perimeters, loading docks, and walkways. As the lighting industry transitions from traditional High-Intensity Discharge (HID) lamps to Light Emitting Diodes (LEDs), the fundamental design of these fixtures has evolved. A primary distinction in the specification of modern LED wall packs is the housing design: gasketed versus non-gasketed (often referred to as ventilated).
Choosing the correct housing type is not merely a matter of preference; it is a technical decision that impacts the fixture's Ingress Protection (IP) rating, thermal management, and longevity. This article details the operational differences, advantages, and ideal applications for both gasketed and non-gasketed wall pack lights, assisting specifiers in navigating the complexities of outdoor area lighting.
Understanding Wall Pack Lighting
Wall pack lights are designed to replace older metal halide or high-pressure sodium fixtures. They are typically characterized by a rugged housing, a polycarbonate or glass lens, and high-lumen output. In the context of US energy regulations, such as the Energy Policy Act (EPAct), these fixtures are often scrutinized for their efficacy (lumens per watt) to ensure commercial energy conservation.
The primary function of a wall pack is to cast light over a specific area adjacent to a building. However, the internal environment of the fixture—how it handles heat, moisture, and particulate matter—is determined by its sealing method.
Gasketed Wall Pack Lights
Gasketed fixtures are designed with a sealed enclosure. A rubber or silicone gasket is placed between the housing and the lens (or between the housing and the heat sink in die-cast models) to create an airtight or watertight barrier.
Design and Construction
The defining feature of a gasketed wall pack is its reliance on physical barriers to exclude external elements. The housing is typically die-cast aluminum, and the lens is sealed tightly against it.
- Sealing Mechanism: The gasket prevents the entry of dust, water, and insects.
- Thermal Management: Because the unit is sealed, heat generated by the LEDs cannot escape via convection (airflow). Therefore, gasketed fixtures often rely on the external housing acting as a large heat sink to dissipate heat through conduction and radiation.
Ingress Protection (IP) Ratings
Gasketed fixtures generally achieve high IP ratings, such as IP65 or IP66.
- IP65: Dust tight and protected against water jets.
- IP66: Dust tight and protected against powerful water jets (heavy seas or strong fire hoses).
This makes them highly suitable for environments where the fixture might be subjected to high-pressure washing or heavy driving rain.
Ideal Applications for Gasketed Fixtures
Due to their sealed nature, gasketed wall packs are the superior choice for "dirty" or corrosive environments:
- Food and Beverage Processing: Facilities requiring frequent wash-downs with high-pressure hoses to meet sanitation standards.
- Coastal Areas: The seal prevents salt spray from entering the housing and corroding the internal LED drivers and circuitry.
- Dusty Environments: Grain silos or woodworking shops where fine particulate matter could clog internal components.
Non-Gasketed (Ventilated) Wall Pack Lights
Non-gasketed fixtures, often called "ventilated" wall packs, utilize a different approach. While they are weather-resistant, they are not airtight. They feature vents or gaps that allow air to flow through the housing.
Design and Construction
These fixtures typically feature a "breathable" design. They often use a polycarbonate lens that is not hermetically sealed to the housing, or they have specific ventilation slots.
- Airflow: The primary advantage is natural convection. Cool air enters from the bottom, absorbs heat from the LEDs and driver, and exits from the top.
- Condensation Management: By allowing air exchange, these fixtures prevent the buildup of condensation inside the lens, which can occur when there is a temperature differential between the inside and outside of a sealed unit.
Ingress Protection (IP) Ratings
Non-gasketed fixtures usually carry lower IP ratings, such as IP54 or IP55.
- IP54: Protected against splashing water from any direction.
- IP55: Protected against low-pressure water jets.
While they are fully capable of withstanding rain and snow, they are not suitable for high-pressure wash-downs, as water could be forced into the internal electronics.
Ideal Applications for Non-Gasketed Fixtures
These fixtures are excellent for general outdoor applications where extreme environmental sealing is not required:
- General Building Perimeters: Standard office buildings, warehouses, and retail centers.
- Parking Lots and Walkways: Areas where the primary concern is visibility and security rather than chemical or water resistance.
- Temperate Climates: Regions without extreme humidity or driving storms.
Comparative Analysis: Gasketed vs. Non-Gasketed
To assist in the selection process, the following table contrasts the key performance indicators of both fixture types.
| Feature | Gasketed Wall Pack | Non-Gasketed (Ventilated) Wall Pack |
|---|---|---|
| Primary Protection | Sealed enclosure (Barrier) | Ventilated enclosure (Airflow) |
| Typical IP Rating | IP65 - IP66 | IP54 - IP55 |
| Thermal Management | Conduction (Heat sink housing) | Convection (Natural airflow) |
| Moisture Risk | Low (unless seal fails) | Low (self-venting) |
| Condensation | Possible on lens interior | Minimized via ventilation |
| Maintenance | Higher (gaskets can degrade) | Lower (fewer failure points) |
| Cost | Generally Higher | Generally Lower |
Technical Considerations
Thermal Management and LED Lifespan
The lifespan of an LED is directly related to its junction temperature (
Tj ). Excessive heat accelerates lumen depreciation and can lead to premature failure.
- Gasketed: Must be engineered with high-quality thermal interface materials and substantial aluminum heatsinks. If the thermal path is compromised, the LEDs can overheat.
- Non-Gasketed: Relies on the chimney effect. As long as the vents are not blocked by debris (e.g., spider webs or leaves), these fixtures often run cooler in high ambient temperatures.
Condensation and Fogging
A common complaint with sealed outdoor fixtures is internal fogging. This occurs when moisture trapped inside the fixture condenses on the cooler lens surface at night.
- Gasketed Risk: If the fixture is sealed in a humid environment, that moisture is trapped. High-quality gasketed fixtures often include a pressure-equalizing valve (breather valve) to mitigate this.
- Non-Gasketed Advantage: The open design allows moisture to evaporate naturally, keeping the lens clear and maintaining light output efficiency.
Maintenance and Durability
Gaskets are subject to environmental degradation. Over time, UV radiation and temperature cycling can cause rubber gaskets to dry out, crack, or compress, leading to seal failure. Non-gasketed fixtures eliminate this failure point, potentially offering lower long-term maintenance costs in standard environments.
Energy Efficiency and Compliance
Regardless of the housing type, commercial wall pack lights in the US market must adhere to safety and energy standards.
UL Listing
Underwriters Laboratories (UL) standards, such as UL 1598 (Luminaires), dictate the safety requirements for electrical components. Both gasketed and non-gasketed fixtures must be UL listed for "Wet Locations" to be used outdoors.
Energy Policy Act (EPAct)
The Energy Policy Act of 2005 and subsequent updates (like EISA 2007) established energy efficiency standards for commercial lighting. Modern LED wall packs, whether gasketed or not, typically exceed these requirements, offering significant energy savings over the HID fixtures they replace. Specifiers should look for the DLC (DesignLights Consortium) qualification, which ensures the fixture meets strict efficacy and quality benchmarks required for utility rebates.
Conclusion
The choice between gasketed and non-gasketed wall pack lights depends largely on the specific environmental conditions of the installation site.
- Select Gasketed Fixtures if the installation site involves high humidity, salt spray (coastal), dust, or requires high-pressure cleaning (food service). The superior IP rating offers peace of mind against element intrusion.
- Select Non-Gasketed Fixtures for standard commercial applications, such as office parks and loading docks in temperate zones. These offer excellent thermal performance through ventilation and reduce the risk of lens fogging, often at a more accessible price point.
By aligning the fixture specification with the environmental demands, facility managers can ensure optimal illumination, reduced maintenance, and extended product life.
References
- Energy Policy Act (EPAct) and Commercial Lighting Standards
https://www.energy.gov - Ingress Protection (IP) Ratings and Thermal Management in LED Luminaires
https://www.energy.gov/eere/ssl/ingress-protection-ip-ratings - UL 1598 Standard for Luminaires
https://www.ul.com/resources/ul-1598-standard-luminaires