A built up roof (BUR) is a traditional roofing system that consists of several layers of reinforcing fabric such as tar paper and felt that are adhered together with tar- or asphalt-based roof cement.
This method of roof construction reduces the amount of heat transfer from the roof and increases its overall fire resistance compared to other roofing materials. The fabric and asphalt layers are usually built up in two to four layers, depending on the required level of durability and weather resistance.
The top layer is typically composed of gravel or crushed stone, which helps protect the underlying layers from weather and ultraviolet radiation. The longevity of the system depends on the quality of the materials used and the maintenance of the roof.
With periodic maintenance and proper installation, a built up roof can last up to 50 years.
Is a built up roof the same as modified bitumen?
No, a built-up roof (BUR) is not the same as modified bitumen. A BUR is a roofing system constructed by applying multiple layers of asphalt felt (tar paper) and asphalt or another waterproofing material that is then reinforced with a layer of fabric (generally polyester or fiberglass).
It is then covered with gravel, which provides additional protection. Modified bitumen is a type of asphalt-based material used in flat roofs in place of traditional hot tar and gravel. Modified bitumen is typically easier and faster to install than BUR systems, and often has a longer lifespan.
What are bitumen roofs?
Bitumen roofs are flat roofs that are created using bitumen, a petroleum-based product. This is usually combined with a reinforcing fabric, such as fiberglass, to create a waterproof and protective barrier.
Bitumen roofs are typically used on commercial and industrial buildings, such as office buildings, warehouses, shopping centers, and factories. Bitumen is an economical option, as it is durable and long-lasting, making bitumen roofs a popular choice for many structures.
In addition to being a cost-efficient option, bitumen roofs are also fire-resistant, low-maintenance, and resistant to mildew, fungus, and degradation from ultraviolet rays. Lastly, bitumen roofs are also environmentally friendly, as they require no asbestos or hazardous materials.
How long will a built up roof last?
A built up roof typically has an average lifespan of about 15-20 years, with proper maintenance, although some manufacturers and contractors may offer warranties up to 25 years. Built up roofs can last longer with regular inspections and maintenance.
Inspections should be conducted annually as well as after any severe weather events. During inspections, the roofer should look for evidence of damage, such as tears and cracks, worn out coatings, and other signs of wear and tear.
An experienced roofer can provide recommendations for repairs or maintenance that may help extend the roof’s life. It’s also important to make sure the roof is maintained clear of debris, such as leaves and branches which can add unnecessary weight and speed up the wear on the roof.
Regular seal coating, patching, and resurfacing of the roof can add many years to the expected life of a built up roof.
Are built up roofs good?
Built up roofs are an excellent choice for many commercial and industrial buildings. They are durable, relatively inexpensive, and energy efficient. Built up roofs are created by coating multiple layers of material, such as asphalt, felt, and gravel, to form a durable, waterproof covering.
The added layers and moisture-resistant material make the roof resistant to damage from weather. Additionally, built up roofs can also come with a reflective coating to help reduce energy costs. The lifespan of a built-up roof is also longer than many other options, as it can last for up to 20 years with proper maintenance.
All in all, built up roofs are a great choice for commercial and industrial buildings due to their cost-effective, energy-saving, and durable design.
What is the difference between built up roofing and single ply roofing?
Built up roofing (BUR) is a method of roof construction that is created by overlapping multiple layers of waterproofing materials such as asphalt, topped with gravel or small stones and tar. Known for its durability and longevity, the building process typically involves the installation of multiple layers of tar-saturated felt and asphalt before the final layer of gravel is added for UV protection.
Building up layers of felt and tar help create a solid and waterproof barrier that does a great job at preventing water from seeping inside the building. The main advantages of built up roofing include its durability, fire resistance, and strong waterproofing capability.
Single ply roofing, on the other hand, is a method of roof construction that utilizes a single layer of material such as EPDM rubber, TPO, PVC, or Thermoplastic Polyolefin (TPO) to waterproof roofs. While BUR creates multiple layers, single ply roofing creates a single layer that functions to protect the roof from the elements.
Often considered easier to install than BUR, single ply roofing is often applied as a liquid membrane that quickly dries and create a rubber-like barrier that effectively keeps water out of the building.
The main advantages of single ply roofing include its relatively easy installation and its superior UV protection compared to BUR.
How do you install built up roofing?
Installing built up roofing involves several steps, including preparing the roofing area, laying the base sheet, applying asphalt, and placing the cap sheet. First, you need to prepare the area by clearing away debris, then laying down felt paper or roofing underlayment.
Depending on the roof’s shape, you may need to cut the felt to fit so that it will provide an even base for the roofing materials. You also need to ensure flashing and vents are properly installed.
Next, you will lay down a base sheet of asphalt. The base sheet should be placed on the felt with the gravel side facing up, and then secured to the substrate with asphalt cement. For best results, the seat material should overlap one another at least one inch.
Once the base sheet is in place, it’s time to apply the asphalt. Asphalt can be applied with a roofing mop, a circular brush, or a roller. When applying, the asphalt should be spread evenly and the work should begin at the eave and come up to the peak of the roof.
Generally, it’s a good idea to have a helper on the roof working in the same direction as you.
Finally, once the asphalt has been applied, the cap sheet should be laid across the roof in the same way as the base sheet and then secured with asphalt cement. Once installed, the roof should be inspected for any imperfections or potential weak spots.
After ensuring no repairs are needed, the job is complete and the built up roof is ready for use.
What is another name for modified bitumen roof?
Another name for a modified bitumen roof is an elastomeric roof. Elastomeric roofs are a viable, durable and cost-effective roofing option that combine a variety of different components to form a single membrane.
Modified bitumen roofing membranes are made of a highly-complex blend of bitumen, polymers and reinforcing fabrics that are heated and rolled together to form a single homogenous roof membrane. This roofing system is often a preferred choice as it has a range of different benefits such as improved flexibility, making the roof resistant to cracking, splitting and heat aging, as well as offering superior resistance against the damaging effects of ultraviolet rays, water and wind.
It is also low maintenance and easy to install, making it popular among many businesses.
How many layers does a built-up roof have?
A built-up roof typically consists of three layers, known as plies. The first ply is a base sheet which is a layer of asphalt-saturated felt, fibreboard, or insulation material. The second ply is a waterproofing ply which is a core layer of asphalt-saturated felt, fibreboard or other related materials.
Finally, the third layer is the cap sheet which is a layer of asphalt or coal tar that is pre-fabricated and which has a mineral granule coating to protect the sheet from sun, wind and rain. The three layers together provide a weatherproof, waterproof and durable roof system.
What materials are typically used for a bituminous roof?
Bituminous roofs are typically made from asphalt and reinforced with a variety of materials, depending on the specific application and required performance. The main materials used are felt paper, fiberglass, polyester, metal, and plastic.
Felt paper acts as a base for the asphalt and provides waterproofing, which is important for keeping the elements from getting into the building. Fiberglass and polyester provide tensile strength and tear resistance and serve as reinforcing materials.
Metal, typically aluminum, is used to provide extra strength and durability. Plastic is also used for waterproofing, and it can also provide additional insulation. Bitumen-based adhesives are typically used to attach the different materials together to form a unified roofing system.
What lasts longer EPDM or bitumen?
Both EPDM and bitumen are materials with very high durability and longevity. However, when it comes to comparing the two materials in terms of how long they last, EPDM has the edge. EPDM roofs can last for 50 years or more when properly installed and maintained.
Bitumen roofs can last for up to 20 years with proper maintenance, but due to the nature of the material, they tend to require roof repairs more often than EPDM roofs. Furthermore, bitumen roofs are more vulnerable to UV damage caused by sunlight, which can cause them to break down and crack more quickly than EPDM roofs.
Therefore, EPDM is generally accepted as being the more durable and long-lasting material of the two.
When should I replace modified bitumen roof?
When it comes to determining when to replace a modified bitumen roof, there are several factors to consider. First, examine the age of the roof. Modified bitumen roofs generally last between 15 and 30 years, depending on the type of membranes and layers used.
Therefore, if your roof is older than the average lifespan, it may be time to replace it.
Second, look for signs of wear and tear. If you notice a sizeable number of cracks, tears, or other damage to the roof’s surface, then you should replace it as soon as possible. Similarly, if the roof seams look separated or raised, then you should replace your roof.
Finally, check for any water damage inside your home. If you notice any stains on the ceiling or walls, or if you detect an odor of mildew or mold, then your roof may be leaking. If this is the case, you should call a roofing professional to assess the damage and recommend an appropriate replacement.
In summary, the best time to replace your modified bitumen roof is when it exceeds the average lifespan of 15 to 30 years, suffers from significant visible damage, or reveals signs of water damage inside the home.
Can modified bitumen roofing be repaired?
Yes, modified bitumen roofing can be repaired. Depending on the extent of damage, there are a few different approaches that can be used to repair modified bitumen roofing. If a small area of the roof is damaged, patches can be made with a patching membrane that is suitable for the exact type of modified bitumen roofing material used.
For larger repairs, an overlay of the entire affected area can be done. This process involves removing the existing material and then installing a new layer of the modified bitumen material. There may be other specialized repair processes that can be done depending on the situation and the type of material used.
It is always best to have a professional inspect the roof and determine the best repair approach for the situation.