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Pella® Impervia® Fiberglass Casement Window

Mulled

Pella Impervia mulled casement windows include two windows of the same size, joined together in the factory. The mulled units ship to you as a combined unit, making installation easier. Both fiberglass casement windows are hinged on the side and swing outward to open. The revolutionary Easy-Slide Operator hardware solution allows you to simply slide to open your windows without the effort of cranking.

  • Two fiberglass casement windows combined together side-by-side in the factory.
  • Made from our proprietary fiberglass, the strongest material for windows.32
  • Patented lock system engages multiple locks, with one easy-to-use lock-lever for lasting security.
  • Product #401003

Configuration: 2-wide

Talk to a Pella Rep for Pricing

Pella Impervia Casement Window Features

  • Strongest Material for Windows 9

  • Patented Easy-Slide Operator Hardware

  • Enhanced Energy Efficiency

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

                      Design, Performance & Size Tables

                      Specifications

                      2D Cross Section

                      2D Elevation

                      3D & BIM

                      Product Literature

                      • impervia casement window cob
                        • cross section of an impervia casement with the easy slide operator
                          • fixed sash and frame impervia window cross sections

                            Pella Impervia Casement Window Specs & Install Details

                            • Unmatched strength and lasting durability for proven performance and sleek style
                            • Tested and designed for the extremes
                            • Operable casement windows available in sizes up to 37-1/2” x 79-1/2”
                            • Fixed casement windows available in sizes up to 71-1/2” x 79-1/2”
                            • Performance class and grade LC40-LC50
                            Frame
                            • Overall frame depth is 3-1/4".
                            • Nominal wall thickness of Duracast® fiberglass composite members is .050" to .090" thick.
                            • Jambs contain factory-drilled installation screw holes on block frame.
                            Sash

                            Sash is Duracast fiberglass composite — five-layer pultruded fiberglass material, reinforced with a Pella patented interlocking mat.

                            Glazing System
                            • Quality float glass complying with ASTM C 1036.
                            • 11/16" dual-pane insulating glass sealed and bonded to sash.
                            • 1" Triple-pane insulating glass sealed and bonded to sash.
                            • High altitude glazing available.
                            Dual Weatherstripping
                            • Continuous, flexible ThermoPlastic Vulcanizate material in dual durometer design, compressed between frame and sash for positive seal on all four sides.
                            • Secondary ThermoPlastic Vulcanizate leaf-type weatherstrip between edge of sash and frame.
                            Easy Slide Operator
                            • Hardened, nickel-coated Steel worm and wheel gears.
                            • Harsh environment approved – ASTM B 117 salt chamber and debris cycling, 20,000 life cycle test approved.
                            • 5lb operational forces available on sizes when FW is ≤ 35" and FH is ≤ 72.5" or FW > 35" but ≤ 36" and FH ≤ 60".
                            Roto Operator Assembly
                            • Operator linkage, hinge slide, and hinge arms are 300 series stainless steel.
                            • Exposed fasteners are stainless steel.
                            • Hardware shall exceed 1,000 hours salt spray exposure per ASTM B 117.
                            • Unison Locking System—A single handle locking system operates positive-acting arms that reach out and pull the sash into a locked position

                            Frequently Asked Questions

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                            FAQs about Purchasing Online

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                            Awards and Certifications

                            • Best Window & Door Product: Easy-Slide Operator

                              International Builders' Show, 2021

                              Best in Window & Door category for product innovation, functionality, design and consumer friendliness.

                            • Best in Show: Easy-Slide Operator

                              International Builders' Show, 2021

                              Best product in the show, with over 200 entries in six categories.

                            • People's Choice winner: Easy-Slide Operator

                              Azure Magazine, 2021

                              Selected as a favorite by the public in the Architectural Products category.

                            contemporary dining room with black impervia windows

                              Pella Impervia

                              Get windows ready to handle virtually anything life throws at them. Pella Impervia products are made from our proprietary fiberglass, the strongest material for windows.9

                              Pella’s exclusive fiberglass will never rot or corrode and resists dents, bends and breaks — and the list goes on. With a tough-as-nails powder-coat finish, your windows will never need to be painted or refinished.

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