Casement vs Double Hung Windows: Which is Better? (2026 Guide)

What Are Casement and Double Hung Windows?

First, let us look at what these windows are.

Karmfönster

A Karmfönster is a window that opens like a door.
It is fixed on one side of the window frame with hinges. Most casement windows open outward.

Casement windows operate with a crank mechanism. You turn the crank, and the window sash swings open.
When it closes, a latch pulls the sash tightly into the frame.

Because of this design, casement windows work very well for sealing air.

Dubbelhängda fönster

Dubbelhängda fönster are very common in traditional houses.
They have two sashes inside one window frame.

• Den upper sash can slide down
• Den lower sash can slide up

This means air can come in from the top or bottom.
A single hung window looks similar, but only the lower sash moves.

Double hung windows slide vertically. They do not swing in or out.

The Key Difference: How They Open and Seal

The most important difference in casement windows vs double hung is how they open and seal.

• Karmfönster swing
• Dubbelhängda fönster glida

This small difference changes many things: air, energy efficiency, views, and maintenance.

Air-Tight Seal

A casement window closes by pressing the sash against the frame on four sides.
This creates a tighter seal.

A double-hung window must leave small gaps so the sashes can slide.
Over time, air can pass through these gaps.

Because of this, casement windows usually have a better air tight seal.

Cost Analysis Casement and Double-Hung Windows

US Market Retail Pricing

Historically, casement windows are more expensive than double-hung windows in the US retail market.

• Double-Hung: Typically 800 – 1400 per window installed. The mechanism is simpler, and competition among vinyl manufacturers keeps prices low.
• Casement: Typically 600 – 1,200+ per window installed. The complex crank hardware and heavy-duty hinges drive up the cost.

The Factory Direct Advantage (Boswindor Strategy)

For builders and developers, sourcing directly from manufacturers can invert this cost dynamic.

• Direct Sourcing: By purchasing directly from high-end Chinese manufacturers (Factory Direct), the cost gap narrows significantly. At Boswindor, our factory-direct pricing for premium Thermal Break Aluminum Casement windows is highly competitive, starting at less than $200 per square meter (supply only). This allows you to procure high-performance aluminum windows for a price comparable to standard domestic vinyl double-hung options. Karmfönster for a price comparable to domestic vinyl double-hung windows.
• Value Engineering: Considering the 40+ year lifespan of aluminum vs. the 15-20 year lifespan of vinyl, the lifecycle cost of aluminum casements is often lower.
• Professional US Installation: Unlike many overseas suppliers, Boswindor provides end-to-end support. We maintain our own dedicated installation team based in the United States, ensuring that your high-performance windows are fitted with precision, backed by local service and expertise.

Energy Efficiency and Energy Savings

Many homeowners care about Energieffektivitet, especially with higher energy costs.

From my experience, casement windows are more energy efficient than double hung windows.

Why?

• When wind blows, it pushes the casement sash tighter into the frame
• This reduces cold air coming in and warm air going out

Double hung windows rely on brushes and sliding seals. These seals can wear out.
Warm air can leak from the middle where the two sashes meet.

If energy savings are important to you, casement windows are often the better choice.

Ventilation and Airflow

Windows are not only for light. They are also for Ventilation.

Karmfönster

When casement windows open, the whole sash moves out.
This allows large airflow.

Also, the open sash can catch wind and guide air into the room.
This is helpful in hot weather.

Dubbelhängda fönster

Double hung windows allow air from the top or bottom.
Some people like opening the top sash to let hot air escape.

However, only half of the window opens at one time.
So airflow is more limited.

If airflow is important, many homeowners prefer casement windows.

Natural Light and Clear Views

Light and views matter a lot in a house.

Casement windows have no bar in the middle.
This gives an fri sikt and helps offer clear views outside.

Double hung windows have a rail in the middle where the two sashes meet.
This blocks part of the view.

If you want more naturligt ljus and clear views, casement windows usually look cleaner.

Window Style: Classic vs Contemporary

Style is another big factor.

Double Hung Style

Double hung windows fit a classic style och traditionell houses.
They are common in older homes and historic areas.

If your house has a traditional exterior, double hung windows may match better.

Casement Style

Casement windows have rena linjer and slim frames.
They fit a contemporary style and modern houses.

In many new projects, casement windows create better curb appeal.

Where Each Window Works Best

From my experience, different rooms need different windows.

Kitchen Sink Area

Above a kitchen sink, casement windows are very practical.
You can turn the crank easily, even if the sink is in front.

With double hung windows, reaching the sash can be hard.

Sovrum

Casement windows open wide and give good access.
This can help with safety and fresh air.

Double hung windows are also common in bedrooms, especially in traditional homes.

Walkways and Exterior Space

Casement windows swing outward.
If there is a walkway, door, or narrow space outside, this can be a problem.

In these cases, double hung windows or sliders may work better.

Underhåll och hållbarhet

Karmfönster

Casement windows have hinges, a crank, and a latch.
These parts should be strong and well-made.

Good casement windows are lågt underhåll, but the hardware needs basic care.

Dubbelhängda fönster

Double hung windows use balance systems to hold the sashes.
These parts can fail over time.

When they fail, the window sash may not stay up.

In long-term use, casement windows often feel more solid.

Security and Safety

Security is important for every homeowner.

Casement windows lock at multiple points around the frame.
This makes them hard to push open from outside.

Double hung windows usually lock at one point in the middle.

Both can be safe, but casement windows often feel more secure.

Replacement Windows and Home Renovation

When people think about byta fönster, they often replace what they already have.

But replacement time is also a chance to improve comfort.

In many home renovation projects, people move from double hung to casement windows
because they want better energy efficiency and airflow.

Others keep double hung windows to match the house style.

Both choices can be right.

Casement vs Double Hung: A Simple Summary

Here is how I see the difference:

• Välja Karmfönster if you want
  • better energy efficiency
  • strong air tight seal
  • more airflow
  • modern style and clear views
• Välja double hung windows if you want
  • classic style
  • windows that do not swing outward
  • easy cleaning from inside
  • a traditional look

There is no perfect window type for every house.

Slutsats

The choice between Casement and Double-Hung windows is no longer just about style—it is about performance engineering.

• Välja Dubbelhängda fönster if you are restoring a traditional home, need to use window A/C units, or have exterior space limitations.
• Välja Karmfönster if your priority is energy efficiency (airtightness), maximizing natural light (slim frames), ventilation, or achieving a modern “glass wall” aesthetic.

For developers and homeowners seeking the highest performance, Thermal Break Aluminum Casement Windows utilizing 6063-T66 alloy och CMECH hardware offer a superior return on investment compared to standard vinyl options. They provide the durability to last 40+ years, the strength to hold massive glass panes, and the modern aesthetic that defines 2025 architectural trends.

Ready to upgrade your project? Explore Boswindor’s range of factory-direct, high-performance window solutions tailored for global projects.