Professional Answers to Common Questions About Built Up Roofing Installation

Built up roofing (BUR) is a multi-layer flat roofing system made from alternating plies of roofing felt or fiberglass mats that are bonded together with hot bitumen, creating a seamless waterproof barrier that has protected commercial buildings for over a century.

LOA Roofing & Construction knows a thing or two about this type of roof because we install built up roofing systems throughout Greater Austin. For commercial property owners in Central Texas, built up roofing delivers exceptional durability under intense sun exposure, strong waterproofing capabilities and reliable resistance to ponding water when proper drainage is designed into the system. With Austin averaging over 2,300 sunshine hours annually and temperature swings from 20°F winters to 105°F summers, choosing the right roofing material matters.

This page answers the most common questions that the LOA team receives about built up roofing installation projects. If you need specific answers fast, call us or request a free roof inspection today.

General Questions About Built Up Roofing

What is a built up roofing (BUR) system?

A BUR system is a flat or low slope roofing solution constructed from multiple layers of reinforcing fabrics. Typically fiberglass mats or roofing felt are embedded in a matrix of hot asphalt or coal tar pitch bitumen. The finished roof surface receives a protective top layer of gravel ballast or a reflective coating for UV and weather protection.

This roofing system has been a commercial roofing staple since the 1880s because its layered design creates built-in redundancy. If one ply is compromised, the others continue protecting the building.

Where is built up roofing typically used in the Austin area?

Built up roofing is designed specifically for flat roofs and low slope roofs with pitches of 3:12 or less. Throughout Austin, Round Rock and surrounding cities, LOA primarily installs BUR on:

  • Office buildings
  • Warehouses
  • Industrial plants
  • Retail centers and shopping malls
  • Schools
  • Medical facilities
  • Multifamily properties with low slope structures

While BUR can work on certain residential flat roofs, LOA typically recommends it for commercial and industrial projects. The system’s weight (4-8 pounds per square foot depending on configuration) and installation complexity make it better suited for structures engineered to handle that load and for owners who can justify the initial investment through long-term performance.

BUR is particularly effective on roofs that see regular foot traffic from maintenance personnel, HVAC technicians and building staff.

Method selected depends on building design, wind exposure, budget, and local code requirements.

What are the main components of a BUR system?

A complete built up roofing system includes several integrated components:

Component Purpose
Roof deck Provides structural support (concrete, steel or wood)
Vapor retarder Prevents condensation in climate-controlled buildings
Rigid insulation Achieves code-required R-values (typically polyiso at R-6 per inch)
Cover board Protects insulation from thermal shock
Base sheet First reinforcing layer, mechanically fastened or adhered
Interply sheets 3-5 layers of felt or fiberglass saturated in bitumen
Surfacing Gravel ballast or reflective coating for UV/fire protection

LOA normally uses fiberglass reinforcement and asphalt-based bitumen meeting ASTM D312 standards for Austin’s climate. The final surfacing choice depends on building use, desired energy efficiency and roof maintenance considerations.

How do I know if BUR is the right choice for my building?

BUR suitability depends on several factors specific to your own roof:

  • Structural capacity: Deck must support 20+ PSF additional dead load
  • Roof slope: Best for flat or low slope applications under 2:12 pitch
  • Existing materials: Condition of current roof deck and any layers to be removed
  • Budget: Higher upfront cost offset by longer lifespan
  • Usage: Equipment placement, maintenance access, walkway requirements

Not every building needs a new roof with BUR. Some situations call for metal roofs, asphalt shingles on steep slopes or lighter single-ply systems.

How long does a built up roofing system last in Central Texas?

A properly installed and maintained BUR roof typically lasts 20-30 years in the Austin climate, with some systems reaching 40 years under optimal conditions. This roof’s longevity depends on several factors:

  • Drainage design: Positive slope (minimum 1/4 inch per foot) that prevents roof ponding problems
  • Installation quality: Proper ply adhesion, sealed flashing and correct bitumen application
  • Maintenance frequency: At least two professional inspections per year
  • Foot traffic levels: Heavy equipment access or constant maintenance activity accelerates wear

LOA’s workmanship warranty and available manufacturer warranties help protect that expected lifespan when owners follow recommended maintenance schedules.


Built Up Roof Installation Process FAQs

What does the BUR installation process look like?

At LOA we follow a systematic approach for every built up roofing installation:

  • 1. Inspection and assessment: We evaluate roof deck integrity, moisture levels and slope conditions
  • 2. Proposal and scope: Written documentation of work, materials, timeline and pricing
  • 3. Permitting: Coordination with Austin Build + Permit Office or county departments (Travis, Hays, Williamson)
  • 4. Tear-off or overlay decision: Based on existing roof condition and local building codes
  • 5. Deck repairs: Addressing any structural issues before installation begins
  • 6. Insulation and cover board: Installing code-compliant thermal protection
  • 7. Ply application: Multiple layers of felt or fiberglass embedded in hot asphalt
  • 8. Surfacing: Gravel embedment or reflective roof coating application
  • 9. Final inspection: Flood testing and punch-list completion

LOA coordinates with building owners and facility managers throughout the roofing project to minimize disruption. We schedule noisy work at appropriate times and maintain clear communication about daily progress so owners are always informed and can make adjustments as needed.

How long does a built up roofing installation take?

Timeline varies based on roof size and complexity:

Roof Size Typical Duration
5,000-10,000 sq ft 3-7 working days
10,000-20,000 sq ft 1-2 weeks
20,000+ sq ft 2-4 weeks (phased)

For larger facilities, LOA phases the work in sections to keep the building weather-tight at all times. Weather conditions such a rain, extreme heat advisories or high winds may affect the schedule. Rain over 1/4 inch halts hot asphalt work entirely.

LOA communicates delays and daily progress through client updates, so you’re never left wondering about the project status.

Can you install BUR over my existing roof, or do you have to tear it off?

Austin building codes typically allow re-cover installations under specific conditions:

  • Only one existing roof layer present
  • Roof deck in good structural condition
  • No trapped moisture detected
  • Adequate attachment for wind uplift requirements

LOA performs detailed inspections including core cuts and moisture scans to determine whether an overlay is safe and code-compliant. While overlays can save 20-30% upfront on roof removal costs, they risk trapping moisture and may shorten system life by 5-10 years.

LOA only recommends overlays when they won’t compromise the new roof’s performance. For approximately 70% of Austin commercial projects, full tear-off of the existing roof deck provides the best long-term value.


Cost, Value and Warranty FAQs

Does an EPDM roof add value to my property?

Built up roofing installation in the Austin area typically ranges from $8-15 per square foot installed. Several factors affect your specific cost:

  • Ply count: 4+ plies add $1-2 per square foot
  • Insulation requirements: R-30 insulation adds approximately $2 per square foot
  • Tear-off vs. overlay: Full roof replacement adds 20-30% to the project
  • Access and staging: Crane requirements can add $5,000-$10,000
  • Surfacing choice: Gravel versus reflective coating

Rather than relying on generic price ranges, commercial building owners and managers in the Austin area can contact LOA for a site-specific written estimate after a free inspection. Every commercial roofing project has unique conditions that affect the final pricing.

Is built up roofing a good value compared to other flat roofing systems?

While BUR may have higher upfront labor costs than single-ply alternatives like TPO roofing, its multi-layer construction delivers superior durability. Here’s how the numbers compare over time:

System Initial Cost Lifespan Annual Cost
BUR $8-15/sq ft 20-30 years $0.50-0.80/sq ft
TPO $5-8/sq ft 15-25 years $0.70-1.00/sq ft
Modified bitumen $6-10/sq ft 20-25 years $0.60-0.90/sq ft

In Austin’s hot, sunny climate, BUR’s thermal mass and surfacing options help with temperature control and long-term performance. The system also offers superior puncture resistance compared to single-ply alternatives, making it cost effective for high-traffic roofs.

LOA can provide side-by-side comparisons with TPO, modified bitumen, EPDM roofing and other roofing solutions during your consultation.

What warranties does LOA offer on built up roof installations?

LOA provides comprehensive warranty coverage on BUR systems:

  • Workmanship warranty: Up to 10 years of leak-free coverage when maintained according to guidelines
  • Manufacturer warranties: 20-30 year prorated material warranties available on systems from GAF, Johns Manville, and other major manufacturers

Warranty requirements typically include:

  • Annual or semi-annual professional inspections
  • Documented maintenance logs
  • Prompt repair of identified issues

LOA reviews all warranty options during the proposal phase so you know exactly what’s covered before work begins. Quality workmanship combined with quality materials from premium built up roofing manufacturers creates a resilient roof backed by solid protection.


Performance, Durability and Maintenance FAQs

How does a BUR system perform in Austin’s heat, UV and storms?

BUR systems excel under Central Texas conditions because of their multi-ply design and protective surfacing. The system handles:

  • UV exposure: Gravel or reflective coatings protect bitumen from direct UV rays, preventing premature aging.
  • Temperature extremes: Thermal mass buffers 100°F+ summer days and winter lows.
  • Wind events: Properly installed BUR achieves FM 1-90 or higher wind uplift ratings of 140-170 mph resistance.
  • Hail: Gravel ballast provides UL 2218 Class 4 hail impact resistance, handling impacts up to 2 inches in diameter.

When designed with proper drainage and correct slope, BUR handles Austin’s 35 inches of average annual rainfall and spring storm events effectively. However, severe weather or very large hail may still cause damage requiring prompt inspection.

LOA engineers drainage carefully with tapered insulation, crickets and diverters to prevent the ponding that causes 40% of BUR system failures.

What routine maintenance does a built up roof need?

Proper maintenance protects your initial investment and prevents minor issues from becoming costly roof repairs. LOA recommends:

Semi-annual inspections (spring post-storm season and fall pre-winter):

  • Clearing debris from roof surface, drains and scuppers
  • Checking for blisters, cracks or ridging
  • Verifying all drains clear within 48 hours after rain
  • Inspecting flashings and penetrations for alligatoring or separation
  • Assessing gravel coverage to maintain 90% minimum

After significant weather events:

  • Visual inspection following hail or high winds
  • Documenting any damage for insurance company claims if needed

Regular maintenance prevents 80% of escalating problems and protects warranty coverage. It's one investment you definitely want to make in your roof.

What are the most common problems with BUR roofs, and can they be repaired?

The most common BUR issues include:

Problem Cause Repair Approach
Blistering (20-30% incidence) Vapor drive from deck moisture Excision and new ply reinforcement
Ridging/splitting Thermal expansion Localized repair with compatible materials
Gravel loss Wind erosion over time Gravel replenishment (every 7-10 years)
Flashing failures UV degradation, building movement Silicone boot repairs, re-sealing

The good news is 70-90% of BUR problems are usually repairable through localized repairs rather than full roof replacement. LOA inspects existing BUR roofs throughout Austin and recommends the most cost effective option, whether that’s spot roof repairs, protective coatings or full replacement when the system has reached the end of its life.

Choose quality roofing for a lasting investment in your home.

Request an Inspection

Dedicated to excellence, our Austin roofing company ensures quality in every project. Contact our skilled Central Texas roofers for a same-day, hassle-free inspection. Call +1 (512) 375-3654 to book your free inspection.

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