sliding and double-hung windows

Sliding windows design makes them more prone to air leaks than casement and awning and hopper windows.

Gliding windows Advantages

Gliding, that is, horizontal sliding windows are increasingly popular, largely because they are easy to open, close and clean. And also because they are less obstructive than other types of windows.

Pros of Sliding windows

Besides being easy to open, close and clean, horizontal sliding windows can be used in big sizes, without strength problems.

Disadvantages of horizontal sliding windows

Horizontal sliding windows are more air leaky (and consequently less energy-efficient) than casement windows, awning and hopper windows. They lack the compression seals, and their design makes them potentially more leaky.

Casement (and awning and hopper) windows are a better option if you are looking for the most energy-efficient design.

Double-hung windows

Double-hung windows have top and bottom sliding sections (sashes), and can be opened by pulling down the upper sash or by pulling up the lower sash. Double-hung windows are popular, largely due to their aesthetics.

Pros of double-hung windows

Double-hung windows are unobtrusive, easy to open, and to clean, and have a classical and attractive design.

Cons of double-hung windows

These windows have the same disadvantage of gliding windows: they are leaky than casement, awning and hopper windows, and less energy-efficient...