The Built Up Reflect Roof combines traditional built-up roofing (BUR) construction with reflective materials to improve energy efficiency and long-term durability. This approach uses multiple asphalt or coal tar layers topped with reflective granules or coatings to reduce heat absorption. It is well-suited for commercial and multi-family buildings in sunny climates. This article explains what a built up reflective roof is, how it differs from standard BUR, and how to choose, install, and maintain it for optimal performance.
What Is A Built Up Reflect Roof
A Built Up Reflect Roof is a traditional BUR system enhanced with reflective components. BUR typically consists of alternating plies of reinforcing fabric and hot-applied bitumen, finished with a protective cap sheet. In a reflective variant, the top layer uses reflective granules or a reflective coating to reflect solar heat back into the atmosphere. This combination preserves BUR’s durability while reducing heat gain, potentially lowering cooling loads and improving indoor comfort.
Materials And Design Considerations
Key materials include:
- Asphalt or Coal Tar Pitches: Serve as the binding layers in BUR. Asphalt is common in milder climates, while coal tar pitches may be chosen for certain waterproofing needs.
- Reinforcement: Asphalt-impregnated felts or fiberglass or polyester membranes provide strength and tear resistance.
- Reflective Cap Sheets: The outer layer uses light-colored mineral granules or reflective coatings to minimize heat absorption.
- Reflective Coatings And Membranes: In some designs, a separate reflective coating is applied to the cap sheet or a reflective membrane is installed as the top ply.
- Ventilation And Drains: Proper drainage, insulation, and ventilation are essential to prevent moisture buildup and ice damming.
Design considerations include climate zone, roof slope, structural load, and compatibility with existing temperatures and building energy goals. A reflective BUR assembly can help meet green building standards and tempering of interior temperatures, especially in hot climates.
Benefits Of A Reflective BUR System
Reflective BUR systems offer several advantages:
- Energy Savings: Reflective surfaces reduce cooling loads by reflecting solar radiation away from the building, which lowers air conditioning demand.
- Extended Roof Life: BUR’s multi-ply construction provides robust waterproofing, reducing membrane punctures and wear.
- UV and Weather Resistance: Cap sheets with mineral granules resist ultraviolet degradation and weathering.
- Low Maintenance: A BUR roof typically requires periodic inspection and minor repairs rather than frequent replacement.
- Compliance: Reflective BUR can help buildings meet energy codes and green building programs that incentivize cool roof performance.
Installation Process
The installation process for a built up reflective roof follows standard BUR methods with a focus on achieving a good reflective top surface. Steps include:
- Surface Preparation: Clean the substrate, repair deck inconsistencies, and ensure proper insulation and drainage.
- Primer And Felt Plies: Apply primers as needed, then install the reinforcing felts with hot bitumen or asphalt.
- Ply Application: Add multiple plies, ensuring proper alignment and no air pockets.
- Reflective Cap Layer: Install the reflective cap sheet or apply a reflective coating with even coverage.
- Quality Checks: Inspect seams, laps, and ballast details to prevent water infiltration.
Professional installation is crucial to prevent leaks and ensure the reflective layer remains effective over time.
Maintenance And Durability
Maintenance for a reflective BUR roof focuses on sealing seams and monitoring the reflective surface. Key practices include:
- Regular Inspections: Schedule biannual inspections to identify punctures, cracking, or granule loss.
- Clean Drainage Paths: Keep gutters and scuppers clear to avoid standing water that can degrade the assortment of plies.
- Top Surface Care: If a coating is used, reapply as recommended by the manufacturer to preserve reflectivity.
- Repair Punctures Promptly: Promptly repair any openings around penetrations or edges to maintain waterproofing integrity.
With proper care, reflective BUR roofs can last 20–30 years or more, depending on climate, maintenance, and installation quality.
Cost And Lifespan
Initial costs for a reflective BUR system are influenced by climate, roof size, and material choices. Compared with non-reflective BUR, reflective components can add modest upfront costs but yield energy savings over time. Typical lifespans range from 20 to 30 years for BUR with good maintenance. Mid-life repairs or partial re-covering are common when the roof reaches the end of its service window.
Environmental And Code Considerations
Reflective BUR roofs support sustainability goals by reducing peak electricity demand and improving indoor comfort with cooler roof temperatures. They may help a building earn credits in LEED, ENERGY STAR, or other green programs. Local building codes may require or encourage cool roof performance on commercial roofs, and some climates have guidance on reflectivity thresholds and long-term performance. It is essential to verify code requirements and environmental incentives with local authorities and utility programs.
Choosing A Contractor And Materials
Selecting the right contractor and materials supports long-term performance. Consider the following:
- Experience With BUR Systems: Look for contractors with proven BUR installations, including reflective top layers.
- Product Warranties: Review warranties for the cap sheet, plies, and reflectivity performance.
- Energy Performance Data: Ask for solar reflectance measurements and expected cooling savings for your climate.
- References And Prior Projects: Inspect completed projects and speak with building owners about maintenance needs and durability.
- Code Compliance: Ensure materials and installation meet local fire and building codes and industry standards.
Practical Considerations For Building Owners
For owners evaluating a built up reflect roof, weigh energy savings against maintenance needs, climate suitability, and long-term cost. A reflective BUR system can be a strong choice in hot, sunny regions where cooling dominates energy use. It blends established waterproofing methods with modern energy performance. Proper design, quality materials, and skilled installation are essential to realizing its full benefits and maximizing roof longevity.