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As a specialist (yes we only make sash windows) we are constantly improving our products. Every day we find new solutions or invent a better component. Many of these improvements go unnoticed, like our balance retaining clips or cill pads to prevent unwanted water seeping under through the frame joints. Simple improvements producing better preforming windows.

Every now and then we really do come up with novel, different ideas that change the way we do things, ideas that we decide to patent. Things like the snap in infill strips, designed to eliminate unsightly brush piles, or Georgi clips a clever invention to mechanically attach Georgian bars so that they are not reliant just upon tape like every other solution.

With a dozen or so patents, it is not unusual for us to find companies who “copy” our ideas (they infringe the patent) Many do so in genuine error, they simply didn’t check if a patent existed or if they were in breach, others however blatantly copy the idea, cashing in on a better looking products and skipping out any of the development cost!

Obviously we seek to protect our inventions for our clients, and prevent other sash window manufacturers from using our specialist knowledge, that’s why you won’t find any other company making butt jointed sash windows, our way*

 Years ago, we worked out that most homeowners who wanted really pretty looking windows for their home, didn’t want shiny plastic, mitre welded products. Some were familiar with wood foil, however the vertical joint lines proved far more important. Welded butt joints were the answer, however there was a problem. As the sections are hollow, most butt joints are open ended, allowing rain water to flood into the room.

What was needed was a new method of construction, one that meant the edges could be sealed yet the appearance would still show the traditional butt joint that customers love about wooden window frames.

Since 2005 we have quietly been making windows with this unique method, we’ve led the sash window field with this authentic, vertical butt jointing method, what’s more, we took out a UK patent for it (GB0516352.2). Today there are many imitators and pretenders who offer pseudo joints but none can match our design or be welded like ours.

It has taken 10 years for door and casement manufacturers to catch up with the idea. Many now have a license from masterframe to offer doors and windows’ using our clever idea, helping homeowners like you find matching products, but nobody is licensed to make sash windows this way, only masterframe.

Fabuolous looking Vintage Windows

Here’s how the windows look from Outside

Here’s how the windows look from Inside

*Others may screw joints together or use corner brackets.