Mock sash windows vs sash windows: what are the differences?

5 min read Windows

Mock sash windows and sash windows are perfect for introducing some historical charm to a property. But if you’ve been thinking of buying either option, you might be wondering what the differences between them are and which is best for you. So, as we install both here at Sheerwater Glass, we thought we’d create this detailed comparison guide.

What are sash windows?

Also known as vertical sliders, sash windows consist of 2 window sashes that sit on top of one another and slide vertically to open and close. Their frame, bead, sash and sill have an ovolo shape, which helps create their classic look.

What are mock sash windows?

Mock sash windows are built from either casement or flush casement windows but are designed in a way that recreates authentic sash windows. However, instead of 2 vertically-sliding window sashes, they have a fixed pane and a movable panel. They also open outward like a traditional casement window.

What materials are mock sash and sash windows available in?

Here at Sheerwater Glass, we offer sash windows in uPVC, timber, timber-effect and aluminium. Mock sash windows are available in uPVC, timber and timber-effect. We’ve taken a closer look at each material to help you determine which best suits your needs.

uPVC sash and mock sash windows

upvc sashes

uPVC is a low maintenance but highly durable material, built to withstand extensive weather exposure. It’s also naturally insulating plus uPVC windows are equipped with multiple heat-trapping chambers, which gives them outstanding energy ratings. Generally, uPVC is the most cost-effective window material, and it has a lifespan of around 35 years, although it can last longer with the right care.

Timber sash and mock sash windows

As timber is the traditional sash window material, opting for it will add a sense of authentic charm to your windows. Timber does require retreating every 6 or 7 years but with proper treatment, it can last for a lifetime. Aside from this, it will only require the occasional clean to keep it looking its best. Wood is another excellent natural insulator that keeps homes warm during the colder times of the year.

Timber-effect sash windows

Timber effect windows are built from uPVC but they are finished in a textured woodgrain finish, which gives them the tone and texture of various types of wood. The result is timber-like aesthetics combined with the practical benefits of uPVC.

Aluminium sash windows

One of the benefits of aluminium window frames is that they are incredibly strong, which means they are slenderer than the other materials. It’s also low maintenance and incredibly durable, offering a lifespan of around 50 years when used for windows. Thanks to the use of polyamide thermal breaks in aluminium frames, plenty of heat is trapped in the home too.

Do sash windows or mock sash windows cost more?

Grey upvc windows

Mock sash windows are a more affordable alternative to authentic sash windows. Therefore, if you are operating on a budget, chances are they will be better suited to your home.

Tilt-in sashes vs outward opening

Our sash windows come with a unique tilt-in function. This allows both window sashes to be tilted inwards, allowing them to be conveniently cleaned from inside the home. This is especially convenient as it means windows on the second-storey or above can be cleaned without a ladder.

Mock sash windows open outwards, so they will need to be cleaned externally. For second-storey windows, this means a ladder will be required to clean them. Anyone who wishes to clean them this way should be very careful, although you could always hire a window cleaner to do this for you.

Sash window vs mock sash window security

Sash and mock sash windows are both designed to keep homes secure, although the hardware they use to do this is very different.

Mock sash windows are equipped with multipoint locks, egress hinges, impact-resistant profiles and toughened glass. Sash windows are equipped with sash window locks as standard, but they can be customised to meet the highest security standards. Sash window restrictors, which limit the amount they can open, can also be fitted.

Which windows are better suited to my home?

Sash 2Aesthetically, some will argue that there is no substitute for the real thing despite mock sash windows being specifically designed to recreate genuine sash window designs. They can each be fitted with Georgian bars, sash horns and various decorative glass options. There is a wealth of colour finishes available for both of them too.

However, sash windows are only suitable for installing to walls that are of a certain depth. Mock sash windows are much slimmer, so properties with slimmer walls can still enjoy sash window aesthetics.

Are you thinking of replacing existing sash windows?

If you already have sash windows that are in need of replacement, we would advise against swapping them out for the mock sash equivalent. Although mock sash windows tend to be cheaper, genuine sash windows can be a big selling point with potential buyers, especially those searching for an authentic period property. In some cases, swapping out authentic vertical sliders for mock sash windows could even damage property value.

Are you interested in a set of authentic sash or mock sash windows for your home? Get in touch with Sheerwater Glass today. We are available to call on 01932 344 415 or you can contact us online.

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