Built-Up Roof Installation Process: Step-by-Step Guide

If you’re exploring roofing solutions for a flat or low-slope property, understanding the built-up roof installation process is essential. Built-up roofing (BUR) systems have been trusted for decades due to their durability, weather resistance, and multi-layer protection.

In this guide, we’ll walk you through each step of the BUR installation process, explain its key components, and highlight what to expect from a qualified contractor.

Whether you’re a homeowner facing storm damage or a commercial property manager evaluating long-term roofing options, this article will give you the clarity you need to make a confident, informed decision.

What you’ll learn: 

• What Is a Built-Up Roof (BUR)?
• Benefits of Built-Up Roofing Systems
• Built-Up Roof Installation Process (Step-by-Step)
• Key Considerations Before Installing a BUR Roof
• Why Trust RayPro with Your BUR Roof Installation?
• Get a Free Consultation for Your Roofing Project
• Frequently Asked Questions (FAQs)

What Is a Built-Up Roof (BUR)?

A built-up roof (BUR) is a time-tested roofing system commonly used on flat or low-slope structures. Known for its layered durability, a BUR system is constructed by alternating multiple layers of roofing felt (or plies) with hot-applied bitumen, typically asphalt or coal tar. This method creates a thick, waterproof membrane that’s then topped with a protective surface layer like gravel or a mineral cap sheet.

BUR systems have been a staple in both residential and commercial roofing for over a century, largely because of their proven performance in demanding conditions. Whether you’re managing a shopping center in need of a resilient roof or a Florida homeowner concerned about storm damage, the built-up roofing system installation offers a dependable, long-lasting solution.

For more context on built-up roofing materials, variations, and system types, check out our in-depth article on built-up roof systems.

Key Components of a BUR System

To understand how a BUR functions, it helps to know what goes into its construction:

• Plies (Roofing Felts or Fabrics): These are layers of reinforcing fabric—usually made of fiberglass or organic materials—that form the foundation of the membrane. BUR systems typically use three to five plies, each bonded together with bitumen to add strength and flexibility.
  
• Bitumen (Asphalt or Coal Tar): Bitumen acts as the adhesive and waterproofing agent between each ply. It’s heated and applied hot to create a watertight bond that fuses the layers into a solid system. Asphalt fumes are regulated due to worker exposure concerns, and OSHA provides safety guidance on handling them during installation.
  
• Surfacing Materials: The top layer protects the roof from UV rays, foot traffic, and environmental wear. This can be loose gravel (commonly seen in tar and gravel roof installation), a mineral-coated cap sheet, or a reflective coating for improved energy efficiency.
  

These components work together to form a robust roofing membrane that resists water, fire, and mechanical damage—making it a go-to choice for properties where reliability and longevity are essential.

Where Are BUR Systems Commonly Used?

BUR systems are best suited for flat or low-slope roofs, where water drainage is a concern and a continuous waterproof barrier is critical. They’re frequently found on:

• Commercial properties like warehouses, retail centers, office buildings, and apartment complexes
  
• Residential buildings with low-slope designs, especially in areas vulnerable to storms or intense heat
  

In regions like Florida, where high humidity, heavy rains, and hurricane conditions are common, the built-up roof layering process provides critical protection. Its multi-ply composition delivers better resistance to water infiltration and wind uplift compared to single-layer alternatives.

Key takeaway: Built-up roofing systems are highly durable, weather-resistant, and well-suited for properties that demand performance and longevity—especially in storm-prone areas like Florida. Understanding their structure lays the groundwork for grasping the full built-up roof installation process, which we’ll break down in the next section.

Benefits of Built-Up Roofing Systems

Choosing the right roofing system is a critical decision—especially when dealing with flat or low-slope roofs that face intense weather exposure. A built-up roof (BUR) stands out for its layered strength, resilience, and long-term value. Below are some of the most compelling reasons property owners continue to trust BUR systems.

Durability and Weather Resistance

One of the top advantages of a BUR system is its ability to withstand harsh environmental conditions. By installing a multi-ply roofing system, multiple layers of felt and bitumen create a thick, reinforced membrane that resists water penetration, high winds, and physical impact.

This durability is particularly important in states like Florida, where roofs must endure tropical storms, wind-driven rain, and extreme humidity. The overlapping layers in a BUR act as redundant barriers—if one layer is compromised, the others continue to provide protection.

Fire and UV Resistance

BUR systems offer excellent protection against external hazards such as fire and ultraviolet (UV) exposure. The top surfacing—whether gravel or a reflective coating—not only shields the underlying membrane from the sun’s degrading effects but also enhances fire resistance. Many BUR assemblies meet Class A fire ratings, as defined in this fire rating classification guide, making them a smart choice for both safety-conscious homeowners and commercial building owners.

This fire and UV resistance also contributes to the system’s long-term performance, reducing the frequency of repairs and the likelihood of premature failure.

Longevity and Energy Efficiency

With proper installation and maintenance, BUR roofs can last 20 to 30 years or more, depending on the number of plies and environmental conditions. This lifespan often surpasses that of single-ply roofing options, especially in demanding climates.

In terms of energy efficiency, BUR systems provide excellent insulation when paired with roof insulation beneath the membrane. Reflective coatings are especially effective at improving energy performance and sustainability in commercial structures.

The reflective top coatings or gravel surfacing also help minimize heat absorption, keeping indoor spaces cooler and reducing HVAC loads—an added benefit for properties in sun-intense regions.

Cost Considerations and ROI

While the flat roof BUR installation process may involve higher upfront labor and material costs compared to single-ply systems, the return on investment is strong. The long service life, minimal maintenance needs, and superior performance in adverse weather translate into lower total cost of ownership over time.

Additionally, BUR systems are often easier to repair and recoat than newer or more complex systems, which can help property owners avoid full replacements when issues arise.

Key takeaway: BUR systems provide a well-rounded blend of durability, safety, energy efficiency, and long-term value—making them a top contender for anyone seeking a proven, cost-effective roofing solution for flat or low-slope properties.

Built-Up Roof Installation Process (Step-by-Step)

Understanding the built-up roof installation process can help you evaluate contractor quality, plan your budget, and know what to expect during the project. Below is a clear, six-step breakdown of how a BUR system is installed—designed to ensure durability, weather protection, and compliance with local building codes.

Note: This process should always be carried out by trained professionals due to the use of hot materials and precise layering techniques.

Step 1 – Roof Deck Preparation

Before installation begins, the existing roof or substrate must be thoroughly prepared. This includes:

• Removing debris, old materials, or moisture-damaged sections
  
• Checking the deck for structural integrity and slope
  
• Ensuring proper drainage and surface readiness
  

A clean, dry, and solid deck is critical for the success of the entire system. Skipping this step can compromise adhesion and reduce the lifespan of the roof. For best results, a thorough roof inspection should be completed before beginning the project.

Step 2 – Base Sheet Installation

Next, a base sheet is applied over the deck. This acts as the initial barrier layer and helps secure the BUR system in place. The base sheet can be attached using:

• Mechanical fasteners (screws or nails with plates)
  
• Cold adhesive
  
• Hot asphalt bonding
  

The attachment method depends on the building type, substrate, and regional regulations. In Florida, for example, wind uplift resistance is a major factor influencing attachment techniques.

Step 3 – Bitumen Application

With the base sheet in place, contractors apply bitumen—either asphalt or coal tar—in hot liquid form across the surface.

• This is known as hot asphalt roofing installation, and it requires careful temperature control and professional safety practices.
  
• The hot bitumen is mopped or sprayed to create a waterproof layer that binds to the plies.
  

Properly applied bitumen forms the essential seal that gives BUR systems their waterproofing capabilities.

Step 4 – Ply Layer Installation

Once the bitumen is applied, layers of roofing felt or fiberglass-reinforced fabric are installed. These are:

• Rolled out one at a time, fully embedded into the bitumen
  
• Overlapped and offset to prevent weak points or gaps
  
• Followed by another layer of hot bitumen to bond the plies
  

This alternating process is repeated for three to five plies, depending on design requirements. This is the heart of the BUR roof construction steps, forming a multi-ply membrane that’s both strong and flexible.

Step 5 – Surfacing the Roof

The top layer—or surfacing—protects the built-up membrane from UV rays, foot traffic, and weather exposure. Common options include:

• Gravel ballast (classic tar and gravel roof installation)
  
• Mineral cap sheet
  
• Reflective or elastomeric coatings
  

In hotter regions like Florida, reflective coatings can improve energy efficiency by reducing heat absorption.

Step 6 – Final Inspection and Clean-Up

A professional contractor like RayPro will always finish with a full quality inspection, ensuring:

• All seams and transitions are properly sealed
  
• Flashings and edges are watertight
  
• Drainage is unobstructed
  

Once the inspection is complete, the crew performs a full cleanup—leaving the site free of debris, excess materials, or hazards.

Key takeaway: The built-up roof installation method is a detailed, multi-step process that requires precision and experience. From deck prep to the final surface layer, each step is crucial for ensuring the long-term success of your flat roofing system. Partnering with an experienced contractor like RayPro ensures that the job is done right—from start to finish.

Key Considerations Before Installing a BUR Roof

Before moving forward with a BUR roofing application process, it’s essential to evaluate a few critical factors that influence project success. Whether you’re a homeowner in Florida or a commercial property manager overseeing multiple buildings, these considerations will help ensure that your investment in a built-up roof is well-informed and properly executed.

Roof Suitability and Assessment

Not all structures are ideal candidates for built-up roofing. Before installation, a professional assessment should determine whether a BUR system is appropriate based on:

• Roof pitch and drainage – BUR is best suited for flat or low-slope roofs with effective water runoff systems
  
• Structural capacity – The added weight of multiple plies and surfacing materials may require load calculations to ensure support
  
• Existing roofing conditions – A full roof inspection helps identify damage or incompatibilities
  

RayPro offers comprehensive roof evaluations to confirm system compatibility and provide tailored recommendations.

Permits, Local Codes, and Insurance

Building code compliance is a non-negotiable aspect of any roofing project. For clients in Florida and other regulated states, it’s especially important to:

• Adhere to local and state roofing codes, including the Florida Building Code (FBC), which outlines wind uplift resistance, fire ratings, and drainage requirements for flat roof systems.
  
• Obtain the necessary permits, which are often required before beginning work on commercial or multi-family structures.
  
• Verify contractor insurance to ensure liability coverage for property damage or worker injury during the project.
  

RayPro is fully licensed, insured, and experienced in navigating code requirements across 17 states. Our team handles permitting and compliance to minimize risk and ensure peace of mind.

Choosing the Right Contractor

The quality and longevity of a BUR roof depend heavily on the expertise of the contractor. Before selecting a roofing partner, ask:

• Are they certified in BUR installations?
  
• Do they provide warranties?
  
• Can they manage the process from inspection to cleanup?
  

At RayPro, we pride ourselves on meeting all of these criteria. With over 17 years of experience, full-service project management, and financing options up to $200,000, we make it easier for both homeowners and commercial clients to move forward with confidence.

Key takeaway: A successful BUR installation starts long before the first layer is applied. Assessing roof suitability, complying with local codes, and choosing a trusted contractor like RayPro are essential steps to ensure a seamless, high-performance result.

Why Trust RayPro with Your BUR Roof Installation?

When it comes to something as important as your roofing system, choosing the right contractor makes all the difference. At RayPro Roofing & General Contracting, we bring unmatched experience, full-service capabilities, and a commitment to quality that sets us apart in the built-up roofing industry.

Proven Experience Across 17 States

With over 17 years of experience and thousands of successful projects completed, RayPro has built a reputation for reliability and craftsmanship across a wide range of environments—from hurricane-prone coastal regions to complex commercial properties. Our team is trained to handle the specific challenges of flat roof BUR installation, especially in high-demand markets like Florida.

Certified, Insured, and Highly Rated

RayPro is fully licensed, certified, and insured to protect your property throughout the entire project. We follow industry best practices and adhere to all state and local building codes. Our clients consistently rate us highly on platforms like Google, BBB, and Houzz, citing our transparency, professionalism, and attention to detail.

Full-Service Project Management and Financing

We handle every phase of your BUR roof installation—from initial assessment and permitting to final inspection and cleanup. Our project managers ensure everything runs smoothly, stays on schedule, and aligns with your budget. Plus, we offer flexible financing options of up to $200,000, making high-quality roofing more accessible for homeowners and commercial property owners alike.

Long-Term Support and Warranty Protection

We stand behind our work with warranties on both materials and labor. After installation, we remain available for ongoing maintenance, inspections, and emergency repairs. Our goal isn’t just to complete a job—it’s to become your long-term partner in protecting your property.

Get a Free Consultation for Your Roofing Project

Whether you’re replacing an aging flat roof, recovering from storm damage, or exploring energy-efficient upgrades, RayPro is here to help. Our experienced team will guide you through the built-up roof installation process with clarity, professionalism, and full-service support every step of the way.

We offer free consultations and site evaluations to assess your roofing needs, answer your questions, and provide a transparent quote—no obligation, no pressure. With expert recommendations, flexible financing options, and trusted project management, you’re in capable hands from start to finish.

Ready to get started?
Contact us today to schedule your consultation and take the first step toward a stronger, more reliable roofing solution.

Frequently Asked Questions (FAQs)