Saudi Conduit Coating Company (S3C): Valley Gutter Waterproofing in Dammam

Project photos

Tap any photo to enlarge. All photos were taken on site by the ETCE team.

The challenge

S3C's building is a multi-bay roof where long valley gutters carry the water from two slopes at once. When gutter seams and laps fail, water backs up under the sheets and drops straight into the plant. The roof edge along the street-side parapet was a second problem area.

What ETCE did

ETCE lined the valley gutters with wide, continuous EPDM that runs up under the roof sheets on both sides, closed the adjoining end laps, sealed the roof-to-parapet edge and flashed the turbine ventilators across the roof.

Failure points treated on this roof

• Eave, valley & box gutters

  Gutter beds lined with a jointless EPDM sheet dressed up under the roof sheets.

• Roof-to-wall flashings & parapets

  Junctions between roof, walls, parapets and platforms sealed and turned up.

• End laps (horizontal joints)

  Horizontal sheet overlaps cleaned and closed with a continuous EPDM strip.

• Turbine ventilators & fan units

  Ventilator bases flashed with EPDM shaped over the sheet ribs.

Materials & method

• EPDM membrane (1.2 mm) cut to width for each detail: UV-stable and flexible at Gulf roof temperatures.
• Promax Bonding Adhesive, rated for surface temperatures up to 120°C, for a permanent bond to the metal sheets.
• Preparation first: old coatings, failed sealant and loose rust removed so the membrane bonds to sound metal.
• Roof-side, zone-by-zone execution so the building below keeps operating with no shutdown.
• Working-at-height HSE: trained crews, full PPE and safety lifelines on every roof.

The result

The valley gutters, the highest-risk part of any multi-bay roof, are now lined without joints, so heavy rain drains away instead of backing up into the building.