Bow Window Replacement Refreshes a 1940 Knoxville, IA Home

This Knoxville home, built in 1940, had aging windows that no longer matched the homeowners’ expectations for comfort or clarity. They wanted more natural light in their living spaces, better insulation against Iowa’s temperature swings and windows that were easier to use day-to-day. Working with Pella Central Iowa, they selected a tailored combination of Lifestyle Series bow, casement and picture windows to refresh two of the most lived-in rooms while preserving the home’s charm.

The new five-wide bow window immediately changed the feel of the living room. Its curved design brings in more daylight and expands the view toward the neighborhood, making the room feel larger and more open. 

Between-the-glass blinds—protected from dust and damage—allow the homeowners to control light and privacy without bulky cords or added cleaning. Dual-pane insulating glass adds a level of comfort the original window simply couldn’t provide, especially in winter.

From the exterior, the bow window softens the front façade and introduces a clean, modern profile that still suits the home’s 1940 architecture.

On the side of the home, new casement windows add airflow and ease of operation. The fold-away crank tucks neatly out of the way, preventing snagging and creating a pared-down look that fits well with the updated exterior. 

Casement windows are particularly effective in older homes that benefit from cross-ventilation. Here, they allow fresh air to move through the living spaces while the tight seal, when closed, supports energy efficiency and reduces drafts.

In the front bedroom, a new three-wide sash set creates a balanced look from the exterior while bringing in soft, even natural light throughout the day. The between-the-glass blinds make it easy to darken the room for better sleep and open it back up in the morning without dealing with dust or tangled cords. 

Energy-efficient insulated glass helps maintain a more stable temperature in a space where comfort matters most, reducing drafts in winter and heat gain in summer. Paired with nearby casement windows, the updated bedroom window layout offers both ventilation and egress while giving the homeowners control over airflow and privacy. 

Slimmer sightlines compared to the original wood windows also provide a clearer view of the tree-lined street, helping the room feel more open and connected to the outdoors without sacrificing comfort or functionality.

Together, the new bow, casement and picture windows create a bright, cohesive look that enhances the home from every angle. The updated glazing reduces heat transfer and helps stabilize indoor temperatures, an especially welcome improvement in a home built more than 80 years ago. 

Inside, smoother operation, cleaner lines and lower-maintenance features—like the between-the-glass blinds and fold-away casement cranks—create a more comfortable daily experience. Outdoors, the white window frames sharpen the home's curb appeal without altering its original personality.