High-Performance Window Upgrade for Historic Northamptonshire Windmill

A really unique and interesting building: surrounding roughly half of a beautifully maintained windmill, this semi-circular structure has had a major upgrade in the form of class 4 airtight Danish aluminium-clad timber windows. Our Danish Window Manufacturing Quality goes into detail about quality assurance in Danish manufacturing.

The installation method for a performance window is very important. If the frame is just sealed via silicone (like a typical UK plastic install), the seal will fail way before the window, and all the money spent on the window would be wasted. We follow a German installation detail: a flexible expanding tape is the primary weather seal – you can just about see this black shadow line surrounding the windows. And, behind that, expanding foam forms the primary airtight seal. Both of these components allow the building and the window to expand, contract and move naturally, without seals splitting and ruining the insulation.

A lot of the ground floor windows were originally sliding sashes – inherently poor at insulating and very draughty. The straight forward solution here is to make a outward opening casement look as though it were a slider… These faux-sash configuration (with a topguided unit above a fixed pane) is certainly not going to fool anyone who knows what they’re looking for. But they’re perfect to maintain the character of a building without compromising on interior comfort. Every other 1st floor window was given a similar configuration, but with an off-centre horizontal split to provide a larger opening area.

There’s a lot of choice when asking for a double door. In this case, we have handles and locks both inside and out. And the doors can hold themselves open at any point up to 90 degrees. Simply putting the handle down the position you’d like it to stay, and it’ll stay there!

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