CoatingsPro Magazine Supplements


CoatingsPro offers an in-depth look at coatings based on case studies, successful business operation, new products, industry news, and the safe and profitable use of coatings and equipment.

Issue link:

Contents of this Issue


Page 28 of 39

COATINGSPRO SURFACEPREP 2015 29 Roof Surface Prep roofs a re not too d if ferent; t hese sur faces shou ld be pressure washed t horough ly. I recommend using a t urbo t ip to remove t he ox id at ion. If some ma intena nce person has used " bu l l," aspha lt-based roof ing products, on repa irs, t his w i l l need to be removed w it h scrapers a nd or w ire br ushes. Factory painted or previously coated metal roof systems need to be primed after pressure washing. Areas of rust need to be primed. If the panel has been previously painted and has rust, check with the system manufacturer for their recom- mendation. Typically, one prime coat will take care of both situations. Here are some additional guidelines to take into account with metal roofs: • Any metal found to have pinholes needs to be replaced, or if the area is isolated, a metal patch needs to be installed over the area. • Fa steners c a n be one of t he big gest sou rces of problems when restor ing a met a l roof. Missing fa sten- ers need to be repl aced , a nd loose fa steners need to be t ig htened or repl aced w it h a l a rger sc rew. If a ny pa nels f ish-mout h at t he hor i zont a ls, you w i l l need to inst a l l some e x t ra fa steners. T h is is ea sy a nd ine x pensive insu ra nce to keep t he pa nels f rom open ing up in t he f ut u re. T h is sa me met hod c a n be used on ver t ic a ls if t hey a re not snug g ly fa stened dow n to t he u nderly ing pa nel or pu rl in. • Vertical seams need to be addressed with flashing-grade materials, three-coursed with fabric and coating or fabric- backed butyl tape. • If the project is a standing seam metal roof, the verticals need to be crimped back to factory specifications. • If there are horizontals, they need to be addressed the same way as verticals whether the roof is a standing seam or S e a m s a n d p o n d i n g a r e as a l s o n e e d attention. Seams need an extra 60 mils (1,524 microns) average thickness of coating. For ponding water, consider a solvent-borne system that offers strength, durability, and ultraviolet (UV)-stability. For metal roofs, consider pinholes, fasteners, vertical seams, standing seams, horizontals, skylights, penetrations, and other detail work. Spray polyurethane foam (SPF) roofs have their own set of considerations, including UV-related ones, you should address.

Articles in this issue

Archives of this issue

view archives of CoatingsPro Magazine Supplements - SURFACE 2015