Skip to Content

Pella® Impervia® Fiberglass Single-Hung Window


Pella Impervia single-hung windows, made from our proprietary fiberglass material, are designed and tested for a lifetime of everyday use. Featuring a stationary top sash and a bottom sash that opens and closes for ventilation, they are a great option for rooms that require access to fresh air. Versatile design features and options help deliver a timeless style to any home. Equal sightlines provide a clean, consistent aesthetic.

Impervia Single-Hung Window Features

Why Fiberglass?

  • Superior strength with our proprietary fiberglass material61
  • Rot- and corrosion-free
  • Tested for the extremes and suitable for all climates
  • Heavy-duty powder-coat finish, including Black


  • Provides outstanding resistance to water, wind and outside noises while delivering energy efficiency, security and ease of operation
  • Interlocking check rail creates a barrier for air and water infiltration
  • Improved security and performance with an exclusive cam-action lock design that pulls one sash into the other
  • Exceptional mulling capabilities for larger, unique window combinations

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.61

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.

Browse Other Impervia Windows

Inside Pella Fiberglass

Pella Impervia windows are created from our exclusive fiberglass formula. A structural mat places rovings in a specific, intricate order to meet our high strength standards. Additional layers of strategically placed rovings are added, then the materials are pulled through a machine, injected with polymer resin and heated. It creates an entirely new, thermoset material which won't break down when exposed to the elements or lose its shape in extreme heat — unlike other materials.

Learn About Performance
cutaway of impervia products

The Pella Difference

We do more than just create windows and doors. We test beyond industry requirements and innovate continuously to make beautifully designed products that you can be proud to own.

For the Pros

Pella Impervia Single-Hung Window Specs & Install Details

  • Made from our proprietary fiberglass material, the strongest material for windows, engineered for lasting durability61
  • Can handle the most extreme heat and cold16
  • Strong, zinc die-cast locking mechanism for enhanced durability and water resistance
  • Single-hung windows available in sizes up to 47-1/2” x 79-1/2”
  • Performance class and grade LC40-LC50


Request a Project Quote

Product Downloads

Options for Pella Impervia Single-Hung Windows

Choosing Your Window


Make a design statement with window combinations. Additional combinations are available. See your Pella sales representative for the complete offering.

For Pros

Combination Design Considerations
  • The superior strength of Pella’s fiberglass allows you to combine standard and special-sized windows. together to create larger, unique combinations, made just for your remodel or new construction project.
  • Available mulls include integral mullion, tight mullion, 1/2” structural mullion or 1” structural mullion with additional steel reinforcements.
  • Solutions that meet design pressure requirements up to DP50.

Interior Finishes

Pella Impervia fiberglass products have a long-lasting factory powder-coat finish in your choice of three colors. Learn more about interior finishes.


For Pros

  • Pella Impervia products are made from our proprietary fiberglass material, the strongest material for windows, engineered for lasting durability.61
  • Our long-lasting powder-coat finish meets AAMA 624, which is a highly-rated fiberglass coating.
  • Exclusive thermoset material won't expand, warp or sag in summer heat, or shrink and turn brittle in harsh winter conditions.

Styling Your Window


Pella's cam-action locks are available in today's most popular finishes.


Grille Patterns

Grilles give the appearance of individual window panes. Pella offers many grille patterns to help enhance your home's architectural style.


Grille Profiles

Grilles-between-the-glass create the classic look of individual windowpanes. Learn more about grille profiles.

3/4" Grilles-Between-the-Glass

Window Enhancements


Flat Screens

Conventional fiberglass screens come standard.

Pella InView™ screens let in 14% more light and are 8% more open for improved airflow compared to conventional fiberglass screens.5

Compare Single-Hung Windows

Explore Other Window Product Lines


Pella products are backed by some of the strongest warranties in the business.

Learn more about Pella warranties