Metal Roof Waterproofing

Metal Roof Waterproofing

This facility is a general aviation operation belonging to the city of Tacoma and situated at the south end of Puget Sound near Gig Harbor, Washington.

The project consisted of a pre-engineered building with a standard “R” panel roof system of approximately 200 squares. The building houses rental aircraft hangar space. Fasteners are through panel hex head screws. They appeared to be stainless and were in very good condition with no visible rust. There was a small area of approximately 2,500 feet previously coated with what appeared to be an elastomeric latex. Weathering and UV degradation had abraded this to a point of non-issue. There was no flaking or peeling and appeared to be tightly adhered. There were small areas of asphaltic plastic cement used as a stop gap patch. The ridge cap had a narrow band of fabric embedded in a product that retained some flexibility but had cracked at critical stress areas, although the adhesion was good.

Inland Coatings specification IM490B5 was the guideline for the application. The roof was power washed with particular attention paid to previously coated areas, asphalt patches and previously repaired ridge cap. A small number of screws were replaced and additional fasteners were required to bring some of the gable trim flashing to an acceptable level. All the fasteners were encapsulated using a refillable caulking gun modified with a bell fitting to fit over the fastener head and deposit a daub similar to a candy kiss. All vertical seams were sprayed and back brushed with Inland’s RC-2250. All of the horizontal seams and penetrations were addressed with RC-2200 Rubber Roof Coating and RPM 400 polyester mesh.

An initial RC-2000 field coat was applied and allowed to set overnight. The following day a final white RC-2000 finish coat was applied. Within several weeks of the completion of this project the Seattle area set a one day record for recorded rainfall. Mr. Rich Mueller, Tacoma Narrows airport manager, commented that while the large “Inland” building had “nary a drop”, other buildings on the field had “interior lakes”. He said it was his intention to address those buildings not protected with Inland Rubber Coating products in the spring.