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What is a Built-Up Roof and How Should It Be Managed?

Posted on May 18, 2023

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What is a Built-Up Roof and How Should It Be Managed?

At North Star Roofing, our flat roofing experts often come across questions about built-up roofs and how they should be managed. Built-up roofs, also known as BURs, are one of the most common types of flat roofing systems used for commercial buildings.

A BUR consists of multiple layers of different roofing materials such as insulation, felt, fiberglass, asphalt, and gravel, among others. This type of roofing system is durable and can last for many years if properly maintained. However, like any other roofing system, it requires proper maintenance to last for a long time and prevent costly repairs during its lifespan.

At North Star Roofing, we aim to share our roofing knowledge with property owners and managers so that you can run your business more smoothly, safely, and economically. In this article, we will explore what built-up roofs are made of, the different variations, and provide tips on how to manage BURs effectively.

What is a Built-Up Roofing System & What’s it Made Of?

A BUR is a multi-ply roofing system that’s more durable than single-ply roofing membranes, like EPDM and TPO. You may also know this roofing system by other names, such as tar and gravel roofing or built-up asphalt roofing.

The installation process of a BUR involves laying down alternating layers of waterproof membranes and asphalt layers, followed by a layer of gravel on its surface. The first layer of the roof is a vapor barrier or waterproof membrane. This layer helps prevent moisture from penetrating a building’s interior space.

On top of this layer, several layers of hot-mopped or cold-applied bitumen are added to create a base for the final surface material, such as gravel or cap sheeting. Insulation materials are also placed between each layer to increase energy efficiency and reduce heating and cooling costs.

built up roof

The Benefits of a BUR

Our team of commercial roofing specialists vouches for the many benefits of built-up flat roofs for commercial and industrial buildings. Here is a detailed explanation of the benefits BURs provide as described by our flat roofing experts:

#1 Durability

Do you know how long a built-up roof lasts? Its lifespan is actually longer than many other flat roofing materials. The multiple layers provide reinforcements to this roofing system making it highly resilient to impacts and harsh weather conditions. On average, a built-up roof can last for around 30 to 40 years, depending on the level of maintenance and your local climate.

#2 Waterproofing

The overlapping layers of bitumen and fabric create a seamless and watertight membrane, reducing the risk of leaks. This composition makes a BUR highly resistant to water penetration, ensuring a dry and protected interior.

#3 Fire Resistance

The top layer of built-up tar and gravel roofing systems involves mineral granules that provide excellent fire resistance to the roof. It acts as a barrier against fire and helps prevent the spread of flames, which generally makes them a desirable choice when trying to meet local fire safety standards and regulations.

#4 Energy Efficiency

There are many types of reflective coatings available for the top layer of BURs to improve their energy efficiency. These coatings reduce heat absorption and the need for excessive cooling. The coatings also protect the roof from water and UV damage, aiding its longer lifespan. Thus, built-up roofs contribute to lower energy costs and promote sustainability.

#5 Sound Insulation

The multiple layers and dense construction of a BUR help reduce exterior noise, creating a quieter and more comfortable indoor environment. This sound insulation is especially beneficial for commercial buildings or office spaces in noisy urban areas.

Overall, BURs provide a cost-effective solution with exceptional durability and longevity that every property owner can add to their list of comparisons.

Common Issues With Built-Up Roofs

Concerns around BURs include algae, water leaks, and surface blisters caused by improper installation, lack of maintenance, and faulty drainage. But these issues can occur with any other roofing material, and the only way to prevent or mitigate them is by taking the right approach to installation. That’s why hiring a reputable commercial roofing contractor can save you a lot of money and hassle in the long run.

Let’s learn more about the potential concerns that may come with a built-up roofing system.

#1 Ponding Water

ponding water on built up roof

If the roof has improper drainage or insufficient slope, water can accumulate in certain areas, leading to ponding. Over time, this stagnant water can penetrate the roofing layers and cause leaks. Roofing contractors may correct this issue by improving the roof’s drainage system, adding tapered insulation to promote water flow, or installing drains and scuppers.

#2 Flashing Failures

Flashing is a crucial component that prevents water infiltration at vulnerable areas, such as the roof edge, penetrations such as vents and chimneys, or intersections where different sections of the roof meet. If flashing becomes damaged, loose, or was improperly installed, it can allow water to enter the building. Roofing contractors may repair flashing issues by replacing damaged sections, resealing joints, or installing new flashing materials.

#3 Blisters or Alligatoring

If you see blisters and bubbles on a built-up roof, it’s called alligatoring, as the surface looks similar to the skin of an alligator. This occurs when the layers of a BUR separate, causing cracked or raised areas on the surface. This happens due to trapped moisture, poor adhesion, or the aging of the roofing materials. Over time, these blisters can break open and expose the underlying layers to water infiltration.

Professionals may address blistering or alligatoring by first identifying the extent and cause of the problem. After that, they may remove the damaged sections along with debris and moisture and repair the underlying layers.

If a BUR was installed over 25 years ago, the contractor may recommend a replacement. This eliminates the risk of unexpected and dangerous roof failures and is a long-term, cost-effective solution for older roofs.

If you have a built-up roof or are considering installing one on your building, you should know all about its maintenance requirements and other related aspects.

Maintaining Your BUR: Best Practices

Maintaining a built-up roof or any type of roof on a commercial building is essential to extend its lifespan, prevent leaks, and ensure optimal performance. 

Here are some maintenance practices you can follow if your building has a flat roof, such as a BUR:

#1 Regular Inspections

Conduct routine inspections of the roof at least twice a year, preferably in spring and fall, and after severe weather events. Look for signs of damage, such as cracks, blisters, punctures, or loose flashing. Inspect the roof’s drainage system and ensure there are no clogged gutters or downspouts.

#2 Regular Roof Cleanings

Your cleaning staff should clear any debris, leaves, branches, or other materials on the roof, especially around the drains. Debris can trap moisture, leading to algae and accelerating the deterioration of the roofing materials.

#3 Have a Preventive Roof Maintenance Plan

Consider implementing a preventive maintenance plan in coordination with a reputed and reliable flat roofing contractor in your area. This plan may include regular roof cleanings, inspections, and minor repairs to address any potential issues before they become major problems.

#4 Use Roof Coatings

Roof Coatings

Roof coatings are another protective measure you can take against weathering elements such as heat, UV rays, rain, snow, and hail. Lastly, keeping up-to-date with weather forecasts allows you to prepare for storms ahead of time by securing loose flashing and filling any cracks or holes in the roof.

As a building owner or manager, it’s essential to work with a reputable and reliable commercial roofing contractor instead of hiring a handyman or the lowest-charging contractor. This is necessary to protect your investment by eliminating the need for multiple repairs in the future and extending the lifespan of your roof.

Professionals with good experience and values will use high-quality materials that won’t require constant upkeep. Remember, taking proper preventative measures saves you time and money down the road.

Choosing a Reputable Flat Roofing Contractor In Your Area

Choosing the right contractor can make all the difference in ensuring your BUR stays in good condition for years to come. Here are tips to make sure you are working with professionals that will help you get the best built-up roof for your building.

What To Look For in a Flat Roofing Contractor

Look for a flat roofing contractor with extensive expertise in commercial roofing, specifically built-up roofs. They should have a proven track record of successful installations and repairs, ensuring they possess the knowledge and skills to handle your project with precision. 

Research the contractor’s reputation by checking online reviews, testimonials, and referrals. They will have positive feedback from satisfied customers, demonstrating their commitment to delivering exceptional service and quality craftsmanship.

Discuss Transparency and Quality Throughout The Project

When selecting a contractor, it’s important to communicate your expectations. You want someone who will keep you informed every step of the way regarding project timelines and any budgeting concerns that may arise. Safety and quality assurance should always be a top priority when you are signing any contract. You’ll want to also discuss your requirements regarding materials, color, and finishing up front.

By taking these steps, you can feel confident that you have chosen the right professionals to manage your BUR properly. Remember that regular maintenance is key to keeping it in good condition. This includes checking for any signs of wear and tear or damage, as well as addressing any issues promptly. With timely, professional management, your BUR can last for many years without causing you much expense or hassle. 

If you are a property owner or manager in Pennsylvania, we are here to help you manage your built-up roof. At North Star Roofing, we are a part of the local community and want to help you take care of your property in the best way possible.

Get a Free Consultation and Estimate on a BUR

If you want to install or manage your built-up roof in Lansdale, or the surrounding areas in Pennsylvania, you can trust the team at North Star Roofing. Our experts have been working in the storm-prone areas of Pennsylvania and New Jersey for many years. We have upgraded and restored hundreds of roofs with high-quality materials and unparalleled workmanship. Our experts are known to go above and beyond to help the residents of our community by offering the most reliable services without having you overspend or cut down on safety or quality. If you are looking for commercial or flat roofing services in your area, call us at (484) 302-7663. We will be happy to offer you a free consultation, roof inspection, and an estimate on your roofing project.

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