Replacing draughty & rotten wooden box sash windows

Energy Efficient UPVC Sash Windows
Energy Efficient UPVC Box Sash Windows
Vertically sliding timber box sash windows have been a feature of the British housing scene for several centuries. They are however dreadfully inefficient and expensive to replace, but if you plan to stay in the property, it is well worth the investment.

In recent years, technological advances in the double glazing industry have led to ever more thermally efficient designs. Nowadays, many replacement UPVC sash windows not only slide up and down, but also both sashes inwardly tilt for ease of cleaning and ventilation.

The energy rated UPVC sash windows that we supply and install have beautiful sculptured UPVC frames, plus the design of the bead and Georgian bar fully integrates with our range of “A” rated UPVC energy saving windows – so property owners can mix and match replacement double glazing styles throughout their home. One thing to bear in mind when replacing wooden box sashes, is the extra cost of box sash removal over casement windows, as traditional replacement vertical sliding sash windows cost more to manufacture and install than side or top hung opening vents.

Hazlemere’s contemporary double glazed vertical sliding sash window range combines the very best in UPVC window technology, with the traditional look of a sash window. It provides the perfect solution for a period home renovation project or a simple replacement for a draughty, single frame sash. Not only are the windows highly energy efficient (with Low E double glazed glass sealed units) with help to keep the heat in, driving down energy bills, but also have strong UPVC frames which are reinforced with aluminium. In addition, each sliding sash itself is reinforced with galvanised steel for added durability, strength and security.

These contemporary replacement box sash windows have concealed gaskets, meaning there are no black lines visible between window and frame, giving a clean traditional look, plus are highly secure as all Hazlemere’s UPVC sash windows are internally beaded for added security, whilst adding a sophisticated sculptured appearance.

All the sealed units deliver excellent thermal performance and come with standard clear double glazing or choice of obscure glass, and the option of internal or external raised astragal Georgian bars. Integral Georgian bars, in my opinion offer, the best combination of traditional look, value for money with ease of cleaning, whilst raised Georgian bars are a more like for like replacement aesthetically with the old individual wooden framed panes, although do cost a lot more and are far far more difficult to clean, plus cut down the amount of light and views. Basically if one prefers the look of applied Georgian bars, money is no object and you don’t mind cleaning windows (or are happy to pay a window cleaner), then hey, who am I to argue, as if that is what customers want, double glazing companies will be more than happy to oblige!


Our showrooms are our shop windows and we have invested heavily to create extensive displays that best showcase our large range of windows, doors and living spaces. You will receive a warm welcome, plus a proper coffee, and the choice to browse at your leisure without interruption.


Want to speak with an Advisor? Give us a call on 08000 825 825

Our friendly team will be pleased to help with any questions you may have.

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