A built-up roof, or BUR, can be expected to last up to 20 years with proper maintenance. The length of time a built-up roof will last will depend on the quality of materials used, the local climate and weather conditions, and the amount of maintenance performed.
High-quality BUR roofs are built up of several layers of felt paper and asphalt, which create a waterproof barrier. The number of layers and materials vary, with some BUR roofs having as many as five layers.
The more layers, the better the protection against UV rays, moisture and sudden temperature changes. Properly installed BUR roofs are resistant to hail, fire, high winds, and ponding water. Regular maintenance should include a visual inspection of the roof and surrounding area, sealant checks, and clearing of debris.
A qualified professional should be consulted in order to determine the life expectancy of a particular BUR roof. Taking proper care of a BUR roof will help to maximize its longevity and ensure it reaches its full life expectancy.
What are common problems with built up roofing?
Built up roofing is a classic and reliable system and one of the most popular roofing methods available, but like any system, it can have its problems. Common issues that can occur with built up roofing systems include poor drainage, resulting in ponded water, cracks or blisters due to thermal expansion/contraction, shrinkage, and excessive interply distortions due to thermal cycles.
Ponded water can cause damage to the roofing system, as well as to adjacent substrates such as walls, windows, and other building components, creating costly repair bills. Poor drainage can also create a breeding ground for fungus and algae, which can degrade the asphalt and the roof membrane, and lead to premature failure.
Thermal expansion and contraction can lead to cracks, blisters, and excessive interply distortions. This can in turn create areas where water can penetrate and cause long-term water damage. Shrinkage can occur within the roof layers and cause splitting and delamination of the roof layers.
It is important to inspect and maintain a built-up roofing system regularly both on the surface and below the surface in order to identify and address any potential problems quickly.
What does it mean when a roof is built up?
When a roof is built up, it means that it has been constructed in layers, with a base layer followed by protective layers and finishing layers. The base layer consists of the main substrate that supports the structure and its components, such as plywood, OSB, sheet metal, and asphalt or felt paper.
This layer is commonly placed directly on the rafters, if it is not used as a structural component. Protective layers consist of materials that help protect the underlying substrate from the weather, such as shingles, tiles, metal, or membrane.
Finishing layers are typically the last layer added, which often provide an aesthetic element and protection from the sun, such as paint or coating, which are usually applied to the uppermost protective layer.
The number of layers and types of materials used will depend on the style and type of roof being installed.
How thick is built up roofing?
Built up roofing traditionally consists of multiple layers of tar and gravel, and these layers vary in depth depending upon the quality, purpose and application of the roof. Generally, the layers of tar and gravel are separated by large sheets of felt and are usually no less than two layers, or two plies.
The plies can range in thickness depending on the application and desired characteristics, but usually the total thickness is between 18 and 30 millimeters (0.75 – 1.2 inches). To ensure that the roof lasts and can withstand the elements, it is essential to use enough tar and gravel and to make sure that the underlying roof deck is strong enough to support the roofing materials.
What is the difference between built up roofing and single-ply roofing?
Built up roofing (BUR) and single-ply roofing are two different systems used to build roofs. BUR consists of multiple layers of asphalt-impregnated felt that are alternately bonded with a hot asphalt, coal tar, or cold-process adhesive and then surfaced with aggregate or a coating.
Single-ply roofing, on the other hand, is a factory engineered membrane consisting of a single layer of synthetic material, such as thermoplastic or thermoplastic rubber, or a reinforced membrane.
The main differences between these two roofing systems are the installation process, durability, service life, and cost. BUR requires more steps during installation and must be applied by a skilled roofing contractor, which makes it more labor intensive and more expensive than single-ply roofing.
BUR is also more durable in terms of resistance to wind and hail damage, and can last up to 30 to 40 years with proper maintenance. Single-ply roofing is a simpler and faster process to install than BUR, and can last up to 25 to 30 years with proper maintenance.
It is often the more budget-friendly option when compared to BUR.
Is a built up roof a flat roof?
No, a built up roof (BUR) is not a flat roof. A BUR is a type of roofing system that is made up of multiple layers of bitumen and reinforcing fabrics that are rolled and hot-mopped or cold-applied to the roof deck.
This type of roof is ideal for areas that experience extreme weather conditions, as the multiple layers provide increased protection and waterproofing. A flat roof is much simpler, constructed of one layer of roof membrane that is stretched across the roof deck and held in place with adhesive and fasteners.
Compared to a built up roof, a flat roof is much less complex, making it more cost effective and providing fewer places for water to pool up.
What are the layers of built up roof called?
The built up roof (also known as a BUR) generally consists of several layers, each of which performs a specific purpose. The most common of these layers are the following:
1. Base Layer: The base layer consists of a layer of heavy gauge, asphalt saturated felts that provide the initial waterproofing membrane for the roof. In many cases, a base sheet may also contain one or more separate mineral surfaces.
2. Mopping Asphalt: The mopping asphalt is applied over the roof deck, and helps to provide a second waterproof layer while also helping to keep the roofing felts in place. Both organic and hot-applied asphalt can be used for this purpose.
3. Reinforcing Fabric: The reinforcing fabric is then laid on top of the mopping asphalt. It generally provides both a physical reinforcement of the roof deck along with the added assurance that the roof system is adhering to the roof specification.
There are several types of reinforcing fabric that can be used, such as fiberglass and polyester fabrics.
4. Built up Roof Membrane: The built up roof membrane is the uppermost layer of the BUR. It generally consists of alternating layers of asphalt saturated felt, or similar material, and asphalt, with the uppermost layer being topped with an emulsion coating or similar material.
This layer helps to protect the felt layers from UV degradation and enhance the overall waterproofing capabilities of the system.
The built up roof is composed of the four main layers listed above, which come together to create a strong, durable, waterproof membrane. In addition to these components, BURs may also include flashings, counter-flashings, and other protective covering.
What is built up bitumen roof?
A built-up bitumen roof is a type of flat roofing system that utilizes a combination of layers of bitumen, fabric and gravel to form a protective sealed surface. Bitumen is an extremely durable material, but it needs reinforcement to make it waterproof.
Fabric and gravel provide that reinforcement.
Built-up bitumen roofs can generally last up to 25 years with proper maintenance. The combination of layers used to create the roofing surface provides protection against rain, snow, high winds and more.
The material is also very resistant to corrosion and is able to withstand a wide range of temperatures without suffering any damage.
The installation process for a built-up bitumen roof involves applying a base layer of bitumen directly to the roof deck. Gravel is then used to provide a wear-resistant layer on the surface and it also helps to protect the bitumen from wear and tear.
Finally, a series of fabric layers are added before the final layer of bitumen is applied. for added durability and protection. Once complete, a sealant is usually applied to the edges to create a watertight seal.
What’s considered a flat roof?
A flat roof is a roof which has a horizontal or almost horizontal surface that is typically covered with roofing material, such as tar or gravel. Flat roofs are typically found in areas where extra space within the roof is desired, such as over an attic or other enclosed area.
While a flat roof offers more usable space than a sloped roof, it does have certain drawbacks. Flat roofs can have issues with drainage and often require periodic maintenance due to the location of the roof and the climate of the area.
Proper installation of a flat roof is critical for long-term performance and durability, and should be done properly for maximum protection against water intrusion. Some of the benefits of a flat roof include cost-effectiveness, improved insulation capabilities, and the absence of large slopes.
What types of flat roofs are there?
Depending on your needs and budget. The most common types of flat roofs are built-up roofs, membrane roofs, and modified bitumen roofs.
Built-up roofs are composed of several layers of roofing felt or asphalt paper laminated together with bitumen and covered with a protective layer of gravel. These roofs are the most economical of the flat roof options and the layers laminated together can accommodate a variety of weather conditions.
Membrane roofs, also known as single-ply roofs, are composed of a single reinforcing membrane made from PVC or EPDM rubber. These roofs are popular because they are lightweight, easy to install, and long-lasting.
Plus, they don’t require gravel like other flat roofs.
Modified bitumen roofs are built with a combination of organic and inorganic base mats, which are modified with a polymer, and then layered with bitumen. These roofs are durable and have a long lifespan, but they also have a higher upfront cost due to the labor required for customization.
What is a flat roof for insurance purposes?
A flat roof for insurance purposes is an insurance policy for a building with a flat roof as opposed to a pitched roof, as is more common. The insurance policy covers risks associated with the flat roof design such as water damage, wind damage and insufficiency in roof structure.
The policy also offers protection from the financial loss or physical damage of any property contained in the building. Flat roof insurance is important for those who own or are responsible for a flat roof, as it can offer peace of mind and financial protection in the event of an accident or natural disaster.
The insurance policy is tailored to the specific needs of the individual so it’s important to shop around and get the best deal.
How thick is the average flat roof?
The thickness of the average flat roof depends on the type of roofing material used and the climate in which it is located. Generally, flat roofs will be between 1-2 inches thick when using asphalt-soaked felt or built-up roofing materials.
If a more durable material is used, such as EPDM rubber, the thickness may increase to up to 10-15mm thick. Additionally, when flat roofs are located in colder climates, extra insulation layers may need to be added, increasing the overall thickness of the roof.
Moreover, the decking used beneath the roofing material can also affect the roof’s thickness; wood decking can add up to an additional 1.5-2 inches. Taking all of this into consideration, the average thickness of a flat roof may vary between 1-4 inches.
Can you put shingles on a flat roof?
Yes, it is possible to put shingles on a flat roof. The main factor to consider is making sure the shingles are installed properly for proper waterproofing. It is typically not recommended because shingles are designed for pitched, sloped roofs and are not as effective on flat roofs since they are designed to shed water.
On a flat roof, the shingles will need to be installed very tightly together with no gaps, but there is still more risk of water pooling. Additionally, while regular shingles are relatively lightweight, they can add too much weight to a flat roof, potentially overloading it and causing a structural issue.
If you are looking to put shingles on your flat roof, it is best to consult a professional who can help determine the best and most secure installation procedure and the most suitable types of shingles.
At what point in degrees would a roof no longer be regarded as a flat roof?
A flat roof is typically defined as any roof that has a slope of 15 degrees or less. As such, any roof with a slope greater than 15 degrees would no longer be considered a flat roof and would instead be classified as a pitched or sloping roof.
While the exact angle at which a roof loses its “flatness” is subjective and dependent on the individual or builder, a good rule of thumb is that any slope greater than 15 degrees would not be classified as a flat roof.
What is the life expectancy of a built up roof?
The life expectancy of a built-up roof, or BUR, depends on several factors. Factors that affect the longevity of a BUR include the quality of the materials used, climate and environmental conditions, the installation process, and the maintenance of the roof.
Generally, a BUR will have a life expectancy of 15-50 years, with the higher end of that range being for roofs that are well-made with quality materials, appropriately installed, and well maintained.
The quality of the materials used to construct the BUR is the foundation of a long-lasting roof. Make sure that you are using materials that are suited for the climate and altitude of where it will be installed.
Appropriate fasteners and coatings should also be used to ensure that the BUR is built to withstand the environment it will be in throughout its lifetime.
The installation process also plays an important role in the life expectancy of a BUR. It is important that the roof is installed correctly, with good technique and the right specifications. This helps ensure the roof stays intact and free from water intrusion and other issues that may cause premature failure.
Finally, the maintenance of the BUR is key. It is important to inspect the roof regularly and make needed repairs promptly. Regular maintenance will help to ensure the longevity of the roof and reduce the chances of major damage that may require extensive replacement or rebuilding.
What are the most common roofing problems?
The most common roofing problems include missing, cracked, or broken shingles, cracked flashing, roof leaks, roof algae, roof sagging, and roof ventilation problems. Missing, cracked, or broken shingles can be caused by extreme weather, improper installation, or damage from animals, and this can lead to major roof leaks.
Cracked flashing occurs when the flashing that seals the perimeter of the roof is not installed properly or it has become worn or deteriorated over time. Roof leaks are the most common source of roof damage and occur when water penetrates through the roofing material, usually due to shingle damage or cracked flashing.
Roof algae are streaked black, gray, or green stains that form on asphalt shingle roofs due to extreme moisture and high humidity. Roof sagging can indicate serious structural problems and usually occurs when the attic is poorly ventilated.
Roof ventilation problems occur when high winds create excessive pressure within the attic that can easily cause damage.
