Built-Up Roofing arrangements are popular in the United States and Canada for more than a century now.
Sheets of heavy paper coated in pine tar and dusted with sand were common in early compositions or built-up roofing (BUR). The use of asphalt for roofing, rather than coal tar, dates back to the 1870s. However, as petroleum refining technology advanced in the early twentieth century, its use became more widespread. Asphalt was picked over coal tar because it was easier to work with and had a broader temperature range.
In the last two decades of the twentieth century, other forms of low-slope roofing systems started to compete with conventional built-up roofs (BURs). Modified bitumen, single-plies, splashed polyurethane foam, metal panels, and fortified liquid-applied roof membranes quickly became popular amongst the newer techniques. Section 1507.15 of the International Building Code, 2012 Edition (IBC 2012) now includes liquid-applied roofing. The NRCA has a segment and specifications for this type of roofing in their Roofing Manual: Membrane Roof Systems.
Built-Up roofing systems are often known as “tar and gravel” or “BUR” roofs. They are made up by alternating layering of asphalt or tar and supporting textiles that are applied directly to the roof. You have the option of selecting the number of layers (or plies) to be installed. A flood coating of asphalt with stone or gravel embedded is the last layer of a built-up roofing system.
While modified bitumen arrangements are similar to BUR, other low-slope options are vastly different. Plastic foam roof insulations appeared in the 1970s, along with new membranes. A vast array of materials and applications to pick from has resulted in a complicated and usually difficult subject matter to deal with.
Built-up roofing has an average lifespan of 15 to 30 years, depending on the region and the materials used, but some structures can stay upright up to 40 years. In general, built-up roofing performs better in sunny climates than it does in colder climes. Built-up roofing has a similar lifespan to composition (asphalt) shingles, which can last anywhere from 15 to 30 years, depending on quality.
Alternating tiers of augmenting plies of roofing felt joined with asphalt or bitumen are implemented to create a roofing system to the desired level. Following the traditional technique, gravel or other surface material is incorporated into the asphalt’s top layer. The insulation and ballast protect the membrane in an inverted arrangement. In order to help reduce Ultraviolet damage and cut the building’s energy expenses, a surface coating can be placed on the roof’s exterior.
Built-up roofs are known for their outstanding waterproofing and UV protection characteristics. They’re low-maintenance, which means they’ll last a long time. They are also more resistant to inclement weather.
However, there are certain challenge areas as well. Installation takes longer, and with the exception of cold built-up, there may be hazardous gases and vapours present. Overall, the expenses of installation are higher, but then the structures last longer as well.
They are highly durable, but like any other roofing, Built-up roofs can deteriorate over time, and proper maintenance is the key to restore these areas.
Regardless of the roofing system you pick, appropriate structuring and aftercare (including frequent inspections) are essential. Several recurring issues can be solved with relatively easy fixes.
Broken/open joints: To repair parted joints or seams, place some cement under the open gap and press it down so that it may adhere to the substrate. If it doesn’t work, cut a huge piece of felt and cover the cracked joint with it. Nails are used to securing it, and then roofing cement is used to hide the nailing. Finally, cover the cement with gravel and let it cure.
Blisters: Smaller blisters can be easily treated by cutting them out with a knife. Allow as much time as possible for the area to dry. Continue cutting down until you hit a dry layer. Remove the felts (plies) and replace them with new felt. Coat the asphalt with chippings once it has been applied. If chippings aren’t available, liquid-applied coatings can be used on top of the restored section.
Waves or undulations: To flatten and level off built-up roofing undulations, consider adding layers on top of the region. Before doing any repairs, make sure the substrate is in good shape, though.
When looking for a roofing contractors Belfast, be sure the firm you choose has the necessary experience and training to install and maintain a Built-Up roof. Using services of a trained roof expert can speed up the process and help you avoid unnecessary complications.