Cut Edge Corrosion
Metal cladding sheets finished with coatings such as Plastisol, a plasticized resin or Kynar 500® PVDF resin-based coatings, are perfectly adapted to our weather conditions and normally have a lifespan of between 15 and 25 years.
These sheets are then cut to size in the factory prior to shipping to the construction companies.
This practise causes the problem because the cut edge leaves a thin line of uncoated metal which is usually not treated at the manufacturing plant prior to fitting by the cladding contractor.
Obviously, the cut edge of the metal sheet is now unprotected and exposed to the elements making it vulnerable to corrosion, and invariably this section of the sheet will rust and peel back.
That’s where we come in by suppling and installing a Cut Edge Corrosion repair system.
We recommend two different Cut Edge Corrosion treatments – Liquasil and Giromax
This is how we treat cut edge corrosion
We do a full and thorough inspection of the cladding and identify all areas of corrosion before submitting our quotation for the works.
1.We prepare the affected area with steam cleaning followed by mechanical hand grinding to bring the affected areas back to a smooth, flat edge.
2.Our approved installers will then apply the recommended system to the manufactures specification.
“Liquasil’s cut edge corrosion treatment has been developed by our Chartered Building Surveying practice to overcome the common problem of cut edge corrosion in metal profile roofs on commercial property.
We appreciate that other systems are available and that there is a long-established procedure to treating cut edge corrosion.
However, our surveyors noticed after inspecting many different metal profile roofs, that the generally accepted methods can actually cause corrosion, rather than solve it.
By actually lifting roof sheets and examining the undersides, it became apparent that roof sheets tend not to rust from underneath and in most cases, the rust is confined to the top of the uppermost sheet.
Consequently, our building surveyors embarked on a study of older roofs that had previously received cut edge corrosion treatment on overlapping sheets, where the gaps between them had been sealed with a mastic or sealant.
On this previously treated and sealed roof, moisture became trapped, resulting in the extensive rusting of both top and bottom sheets. Still think gap sealing is a good idea?
In most cases, it became apparent that rather than solving the problem of cut edge corrosion, the sealing of the overlapping joints can actually create as many issues as it solves.
The reason is simply that by walking on the roofs, the seal between the roof sheets is often broken, though this break can rarely be seen by the human eye, unless pressure is placed on the roof sheets to identify the break.
Even installers of these systems agree with our analysis and often report that they hear a characteristic “popping sound” of the seal breaking as they walk across the roof during their installations.
The result is that during rainfall, water enters the broken seal through capillary action and becomes trapped between the upper and lower roof sheet and rust begins to form from underneath. Eventually rust breaks through the original treatment.
Closer examination of these surface rust spots often identifies a much larger rust problem than originally existed with the cut edge corrosion.
Our own tests on previously sealed edges have consistently shown that water becomes trapped and rust develops from the underside of the roof panels, rusting both top and bottom sheets in the process.
We therefore question the logic of sealing overlapping roof sheets and our discussions with metallurgists and roofers back up our assumptions.
Consequently, the Liquasil cut edge corrosion treatment system has been designed to treat only the top sheets and not to seal overlapping roof sheets.
This results in a far easier application method, significant material and labour savings and an altogether more robust solution to cut edge corrosion problems.
We do, however, offer an optional gap sealer (lapsil), to satisfy building surveyors who prefer to specify sealing the overlapping roof sheets.
Because Liquasil Ltd is owned by building surveyors, our liquid roofing solutions are designed to actually solve the problems associated with commercial roofs.
The Liquasil Cut Edge Corrosion System is so good, that from November 2016, all installations with a contract value exceeding £10,000 will come with a 12 year latent defects warranty as standard, when installed by a Liquasil Approved Installer.
Giromax Seamsil® Silicone Seamsil 100 System
Edge Sealing and Protection
SEAMSIL® is a unique flexible silicone remedial system developed by Delvemade Limited in conjunction with GE Silicones, part of the General Electric Company of America.
The system, initially developed to solve the problem of cut edge corrosion on steel roofing has now become recognised as the most versatile and effective protection treatment in any situation where exposed metal is subjected to aggressive moisture conditions. For this reason, manufacturers across a variety of industries are specifying SEAMSIL® in the production of fabrications where resistance to corrosion damage is a requirement.
- Exceptional adhesion to cleaned and prepared surfaces and cure to provide a tough elastic seal, effectively encapsulating the damaged area to restrict further deterioration.
- Proven long life, being unaffected by UV or extremes of weather and temperature.
- Excellent elastic and flexibility properties to withstand normal surface movements.
The SEAMSIL® system has been developed against a background of decades of experience of roof refurbishment and repair and is designed to be “user friendly” in application. A three-stage system, comprising a gun applied sealant, a brush applied Basecoat and a brushable Topcoat,
The Seamsil 100 System carries a 10 year manufacturer’s warranty.
Why not contact us today and speak to the Industrial Painting Project Management experts.
With 40 years of experience you can trust us to get the job done right. Call us now on 0330 124 2616.