As the construction industry increasingly turns to green building, roofing is transitioning towards more light-transmittable materials. What better way to conserve energy but to allow natural light to fill the room through skylights? Various technological advancements have made it possible to design roofs that allow natural daylight to seep in while keeping the glare out. These also help in the conservation of energy.
While skylights brighten up a room, they also often spring leaks. Unfortunately, by the time these are diagnosed, they have already caused severe damage to the ceiling, causing water to flood into the room. Typical causes of a leaking glass or polycarbonate roof are inadequate flashings, loose capping or perished seals. Sealants can fix seals temporarily, but are never the answer. Another major cause of leakage, especially in the metal roofs, is fastener movement. Thermal shocks cause fastener to loosen and back out.
In a bid to help leakage problems, 3M launched a brand new roof-sealing application—a unique and dependable product called 3M’s Extreme Sealing Tape, 4412 N. This product is a singlecoated, pressure-sensitive adhesive tape, designed for difficult sealing applications. The backing on this tape is an ionomer film, which is very tough, flexible and abrasion resistant. The soft and thick acrylic adhesive has excellent sealing properties, and outstanding outdoor durability. This single-coated tape is designed to seal over an existing joint, seam or penetration. The adhesive is designed to adhere well over the ionomer film, enabling overlapping of the tape, and thus providing a tight seam to itself and the joint or seam to be sealed.
The long-term high temperature tolerance (days and weeks) of this tape is 93 degrees C, while the short-term high temperature tolerance (minutes and hours) of the film is 149 degrees C. The immersion resistance, temperature resistance, high humidity resistance and temperature cycling resistance of this tape vary with respect to external factors. It has been subjected to accelerated aging tests, conducted at 3M Weathering Resource Centre at St. Pauls, Minnesota. Over 2,000 hrs of accelerated aging exposure indicated no cracking or chalking of 3M Extreme Sealing Tape 4412 N. The tape still had 10 lbs per inch width of peel adhesion strength.
Taking about this product, Kaushik Nag – Business Development Manager (Construction Market Industrial Adhesives and Tapes Division), 3M explains, “The biggest challenge is to quantify the effectiveness of sealing joints, and its cost-to-benefit ratio when considering the lifecycle cost of the product.”
Compared to traditional sealants used on metal roofs or skylights, 3M Extreme Sealing Tape 4412 N is designed for difficult sealing applications. The tough, yet flexible and abrasion-resistant tape exhibits excellent UV resistance, and easily conforms over contours, edges, rivets and screw heads, resulting in an extremely fast, clean and easy way to seal.
Typical application areas are not only limited to skylights and pre-engineered roofs; it is also an excellent choice for the roofs of buses, trailers or vans. It also assists in the sealing of old storage joints. With time, the advantages become even more obvious.”
The simple application of Extreme Sealing Tape makes it a proactive solution. However, in most cases, the product is summoned after the damage has been done. The first step is to remove the existing sealant in the gap that was leaking, as there may be entrapped water inside. The surface has to be cleaned using a combination of isopropyl alcohol and water (50:50). 3M Adhesion Promoter 111 can be applied on the cleaned surface where the tape will be applied.
The tape will then be applied over the joint with the non-stretch liner in place, from corner to corner. With the non-stretch liner still in place, the tape is to be pushed into the seam joint using a hard squeeze. It will then be rolled down with a roller. The non-stretch liner is to be removed by peeling from a corner. Once the liner is removed, the tape will appear flat in finish. If the liner remains, the finish will be glossy. The final roll down will be performed using a soft roller again, using firm pressure. The entire operation can be completed in a day. From rain gutters to flashing and vents, Extreme Sealing Tape is a sure winner over sealants. With no sticky residue, fast installation and proper aesthetics, this tape can help to seal any ceiling problem.
For further details, please log on to www.3M.com/VHB