Base Cap Faqs – Install System Questions

Design & Selection – Vent Tape Not Required        Plastic H & U-Profiles Yellow        What not to do – Ouch!

Screws with Base & Cap       Screws in body of sheet       • Base & Cap cut (for your poly sizes) to fit in crate 

  • Seal between Cap and poly. panel doesn’t look weather tight.   No Gaskets Required – Cap provides proper seal, even on 5º pitch. Glass & acrylic are hard materials, requiring gasket type seals. Polycarbonate is resilient, when Cap snugly installed, pressure of legs of Cap causes the poly to give slightly, creating a watertight seal.
  • I do not see vent tape in your drawings? Vent tape is typically used in U-Profiles of plastic that, not only yellow, but also fit loosely. Our U-Profiles fit tight, Vent Tape Not Required – see Base & Cap, key is follow Install Details.
  • Where to use silicone? Details indicate use of silicone. The key is follow Install Details.
  • Quantity of silicone required? 1 tube silicone will produce 25 linear feet of 1/4″ x 1/4″ silicone bead.
  • Existing rafter framing is 4 ft. on-center, but the sheet is 4 ft. I would like to use your Base & Cap System?  Cut sheet to 47″ wide .
  • Where is Aluminum Tape used?  See Base & Cap Install Details. The key is follow Install Details.
  • Building a sunroom and would like polycarb and the Base & Cap System on the roof and glass on the vertical walls. Fill wall openings with windows and patio doors. Fill in above gable end windows or doors with poly.
  • Touch up paint? For bronze use Rust-Oleum, Bright Coat, Metallic Finish – Dark Bronze #7713.
  • Roof Access Notes for Base, Cap, screw & flashing sealant via step ladder positioned in empty roof bay to left or right of already installed poly. Install of 1st & last sheet done by ladder outside structure.   Work from upper step and reach over sheet.  4 ft wide sheets are easy to reach over to set screws and best for roofs.  Start at one end, work towards other end.  Do all steps as you go and it will not be necessary to gain access to the roof again.
    Access to the ridge to install and/or seal the flashing may also be achieved by placing 2ʼ x 3ʼ sheets of plywood, with Non-Slip Rug Padding glued to the back, over the installed poly. Use 3M #90 spray glue.  Advance planning to proceed as described in the previous paragraph may result in an easier install.  Your situation and skill level will dictate the best way to proceed.

Other Questions:      Main FAQ Page    Polycarbonate    General FAQs     Hardware & Tape FAQs

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