Roofing project
Built-up roofing system installation on a commercial building in Austin, Texas

Built-Up Roofing Systems

The original flat roofing system with over a century of proven performance. Multi-ply waterproofing engineered for Central Texas commercial buildings that demand maximum durability.

What Is Built-Up Roofing?

Built-up roofing (BUR) is the original flat roofing system and has been protecting commercial buildings for more than 100 years. Also commonly known as "tar and gravel" roofing, BUR consists of alternating layers of asphalt and reinforcing fabrics called plies, topped with an aggregate surfacing of gravel or a mineral cap sheet.

This multi-layer construction creates an exceptionally durable, waterproof membrane that has stood the test of time across every climate zone in the United States. For Central Texas building owners looking for proven, reliable flat roof protection, BUR remains one of the most trusted options available.

At Stanley Built Roofing, we install, repair, and maintain built-up roofing systems for commercial properties from Austin to San Antonio to Waco. Whether you are re-roofing an existing BUR system or evaluating your options for a new construction project, our team provides honest assessments and expert workmanship backed by our commitment to quality.

How BUR Works

A built-up roof is constructed in layers, with each layer adding waterproofing redundancy. The typical installation sequence is:

Base sheet — mechanically fastened or adhered to the roof deck as the foundation layer
Asphalt layer — hot-mopped or cold-applied asphalt bonding the plies together
Felt ply — reinforcing fabric (fiberglass or organic) embedded in asphalt
Repeat asphalt + felt ply — typically 3 to 5 total plies for maximum protection
Aggregate surfacing — gravel, slag, or mineral cap sheet for UV and weather protection
Expected Lifespan
20 – 30+ Years With Proper Maintenance

Advantages of Built-Up Roofing

Built-up roofing has earned its reputation through more than a century of reliable performance. While newer single-ply membrane systems have gained market share, BUR continues to be the right choice for many commercial applications — particularly those demanding maximum durability and redundancy.

Proven 100+ year track record — the most time-tested flat roofing system in existence
Multi-layer redundancy — if one ply is compromised, the layers beneath continue protecting
Fire resistant — gravel surfacing provides excellent fire resistance ratings
Durable foot traffic surface — handles heavy equipment loads and maintenance crews
Low maintenance — requires minimal upkeep when properly installed
UV protection — gravel aggregate reflects solar radiation in Central Texas heat

Best Uses for BUR

Built-up roofing is not the right choice for every building, but it excels in specific applications where its strengths make a real difference. BUR is ideal for:

Older commercial buildings where the roof structure can support the additional weight
Industrial facilities with heavy rooftop equipment and frequent foot traffic
Properties that need maximum durability and can accommodate the heavier system weight
Buildings where fire resistance is a priority concern

For buildings where weight is a concern or faster installation is preferred, TPO or EPDM single-ply systems may be a better fit. We evaluate each building individually and recommend the system that best matches your needs and budget.

Types of Built-Up Roofing

The surfacing layer is the most visible component of a BUR system and has the biggest impact on performance, weight, and appearance.

Smooth-Surfaced

A lighter-weight option without aggregate. Requires a protective coating (typically aluminum or elastomeric) for UV protection. Easier to inspect and maintain. Good choice when structural weight is a concern.

Mineral Cap Sheet

A middle-ground option using a factory-applied mineral granule cap sheet as the top layer. Moderate weight with good UV resistance. Available in limited colors for improved aesthetics.

BUR in Central Texas Heat

Built-up roofing performs well in the Central Texas climate, but there are practical considerations specific to our region that every building owner should understand.

The gravel aggregate surfacing on a traditional BUR system reflects a significant amount of solar radiation, which helps reduce cooling loads during our long, hot summers. This thermal mass also moderates temperature swings between day and night, reducing the expansion and contraction stress that degrades many roofing systems over time.

One important factor to plan for: hot-applied BUR installation produces noticeable asphalt odors. If your building is occupied by tenants or customers, we schedule installation to minimize disruption — typically working on weekends or during low-occupancy periods. Cold-applied BUR alternatives are also available when odor is a primary concern.

For buildings where energy efficiency is a top priority, a reflective roof coating can be applied over an aging BUR system to improve solar reflectance without requiring a full tear-off.

BUR Repair & Maintenance

One of the advantages of built-up roofing is that it can be repaired and maintained cost-effectively when issues are caught early. Common BUR repairs include:

Patching — localized repairs for punctures, blisters, or splits in the membrane
Re-coating — applying protective coatings to extend the life of smooth-surfaced BUR
Flood coating — a rejuvenating asphalt coat for aging BUR systems nearing end-of-life
Flashing repair — addressing failures at walls, curbs, and penetrations
Drain clearing — preventing ponding water from accelerating membrane deterioration

When a BUR system has reached the end of its useful life, a silicone roof coating can often be applied directly over the existing membrane — extending roof life by 10 to 20 years without the cost and disruption of a full tear-off. For roofs with widespread damage, a complete flat roof repair or re-roofing may be the more cost-effective path forward.

BUR vs Modern Single-Ply Systems

Building owners often ask whether a built-up roof still makes sense compared to modern single-ply systems like TPO and EPDM. The honest answer is: it depends on your building.

BUR is heavier and more labor-intensive to install than single-ply membranes, which means higher upfront costs and longer installation timelines. However, the multi-layer construction provides redundancy that single-ply systems cannot match — if one layer is damaged, the layers beneath continue to protect the building. This makes BUR particularly well-suited for industrial environments where the roof takes regular abuse from foot traffic, equipment, and maintenance crews.

Single-ply systems like TPO are lighter, faster to install, and often more cost-effective for commercial buildings that do not need heavy-duty performance. They also offer superior energy efficiency with factory-applied reflective surfaces.

For modified bitumen roofing — a system closely related to BUR that uses polymer-modified asphalt sheets — the installation process is faster and produces less odor while still delivering multi-layer performance.

We do not push one system over another. After inspecting your building, we will recommend the roofing system that provides the best value for your specific situation. Schedule a free inspection and we will give you an honest assessment.

Built-Up Roofing Questions

Common questions about BUR systems for Central Texas commercial buildings.

Built-up roofing is the original flat roofing system, consisting of alternating layers of asphalt and reinforcing fabrics called plies, topped with gravel or a mineral cap sheet. Also known as "tar and gravel" roofing, BUR has been protecting commercial buildings for over 100 years and remains one of the most reliable waterproofing solutions available.

A properly installed and maintained built-up roof typically lasts 20 to 30 or more years. Regular maintenance including annual inspections, drain clearing, and timely repairs can push the lifespan toward the higher end of that range.

Each system has its strengths. BUR offers superior multi-layer redundancy and handles heavy foot traffic well, making it ideal for industrial applications. TPO and EPDM are lighter, faster to install, and more cost-effective for many commercial buildings. The best choice depends on your building's specific needs, usage patterns, and budget.

Yes. BUR roofs can be repaired through patching, re-coating, or flood coating. Isolated damage from punctures, blisters, or splits can be addressed without replacing the entire roof. If damage is widespread or the membrane has reached end-of-life, a coating system or re-roof may be more cost-effective.

Hot-applied BUR systems produce noticeable asphalt odors during installation. We schedule installations to minimize disruption to tenants and business operations. Cold-applied BUR alternatives are also available and produce significantly less odor.

Most commercial BUR systems use 3 to 5 plies of reinforcing fabric alternated with asphalt layers. More plies provide greater waterproofing redundancy and durability. We typically recommend 4-ply systems for Central Texas commercial buildings to balance performance, weight, and cost.

Need a BUR Assessment?

Whether you are evaluating a new built-up roof or need repairs on an existing one, our free inspection will give you honest answers and clear options.