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Pella® Impervia® Fiberglass Double-Hung Window

Mulled

Two Pella Impervia mulled double-hung windows are joined together in the factory and shipped as one unit. This creates a dramatic window opening in the home, doubling the size of a single window. Each window features two sashes that raise and lower independently for ventilation. These fiberglass windows are resistant to water, wind and outside noises — while delivering energy efficiency, security and ease of operation. The durable powder-coat finish resists chalking, fading and scratching.

  • Two fiberglass double-hung windows combined side-by-side in the factory.
  • Commercial grade strength and performance.15
  • Sashes tilt in so you can clean both the interior and exterior of the glass from inside your home.
  • Product #401001

Configuration: 2-wide

Online Only Price
From $2,104.41

Pella Impervia Double-Hung Window Features

Design Options

Solid-Color Frames

    • black fiberglass frame

      Black

      • brown fiberglass frame

        Brown

        • white fiberglass frame

          White

          • morning sky gray fiberglass frame

            Morning Sky Gray

            • tan fiberglass frame

              Tan

            Downloads & Specifications

            Pella Impervia Double-Hung Window Specs & Install Details

            • Timeless style and proven performance with unmatched strength and lasting durability
            • Handles the most extreme heat and cold9
            • Interlocking checkrail creates a barrier for air and water infiltration
            • Double-hung windows available in sizes up to 47-1/2” x 79-1/2”
            • Performance class and grade LC30-LC50

            Frame
            • Nominal wall thickness of Duracast fiberglass composite members is .050" to .080" thick.
            • Frame corners are mitered, joined and bonded with corner locks and mechanically fastened with injected polyurethane adhesive.
            • Frame has 10° slope sill.
            Sash

            All sash members have mitered corners bonded with corner locks and sealed with injected polyurethane adhesive.

            Weatherstripping
            • Fin-type pile on jambs, top rail and stile of upper sash
            • Vinyl-wrapped foam at sill on frame and bottom rail of lower sash.
            Glazing System
            • Quality float glass complying with ASTM C 1036.
            • 11/16" insulating glass sealed and bonded to sash.
            • High altitude glazing available.
            Hardware
            • Galvanized block-and-tackle balances connected to sash with polyester cord and concealed within the frame. 
            • Two locks are installed on units 37" wide or greater.
            • Locks are zinc die-cast, self-aligning cam action factory-installed on the interlocker to match finish. 
            Additional Hardware options
            • Optional limited opening device available for field installation on vent units in foamed PVC to match interior of unit; nominal 3-3/4" opening.
            • Device allows window to open less than 4” with normal operation, with a release mechanism that allows the sash to open completely. Complies with ASTM F2090-10.

            Frequently Asked Questions

            FAQs about My Product

            FAQs about Purchasing Online

            contemporary dining room with black impervia windows

            Pella Impervia

            When it comes to performance, Pella Impervia is an overachiever. Windows with dual-pane glass offer energy-efficient options that will meet or exceed ENERGY STAR® guidelines in all 50 states.1 Further increase your energy efficiency with optional foam insulation.

            With outstanding resistance to water, wind and outside noises while increasing energy-efficiency, security and ease of operation, Pella Impervia windows are an excellent choice for your home.

            Fiberglass Window Tips & Advice

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