These are 3 different contracts for which WeDB has drawn up a series of projects involving extraordinary maintenance works on the roofs of various existing buildings at Sigonella, distributed in the different bases of NAS I, NAS II, Marinai and Niscemi. The objective is to eliminate the causes of water infiltration, and bird intrusion into the spaces below the roofs including the replacement or repair of downspouts, gutters and flashings. In almost all of the buildings under review, the project also included repairs to damaged interior areas.
A hydrological precipitation study was conducted to calculate and verify the rainwater harvesting system, which was modified and/or replaced in almost all buildings; new gutters and downspouts suitable for rainwater disposal were designed.

In accordance with current standards, calculations were carried out to verify the tear strength of the anchoring systems of the panels and bituminous membranes to the roofing slabs, using significant wind thrust values, as required by the contract specifications.

Individual interventions by building are analyzed below.
B175 – Midtown – NAS I
B314 – Child Development Center – NAS I
B318 – Community Center – NAS I
The roof consists of an exterior tile cladding, an interior cladding of rigid polyurethane insulation panels, and a steel support structure.
The intervention the filling of holes on the roof insulation panels caused by birds, with foam interposed to the wire mesh; the whole was sealed with adhesive tape placed on both sides.
B459 – Engine Maintenance Shop – NAS II

The roof system consists of a flat roof made of multilayer panels (sheet metal and insulation) interspersed with 8 large skylights.

The repair involved applying sealant along the edges of the skylights and vents present; rivets were also applied where missing, on the joints between panels.

B471 – Community Bank – NAS II_400sq.m.
B2569 – Youth Center – MARINAI_110sqm.
The typical roofing system is a barrel roof consisting of domed roof panels and bituminous membrane with a mineral finish. The intervention included removal of the existing mineral layer and installation of an elastomeric polyurethane liquid waterproofing membrane, interposed with fiber-reinforced mesh.

B459 – Engine Maintenance Shop – NAS II
B546 – Aircraft Ground Support Equipment (GSE) Shop – NAS II.
The intervention included the installation of epoxy primer, and layers of nonwoven fabric and polyurethane membrane; the latter further reinforced at walkways around the external air handling units.