Who we are

Cleartherm Glass Sealed Units was established in 1988. Back then, five employees manually produced 400 sealed units per week.

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Quality is important to Cleartherm Glass Sealed Units Ltd because we value our customers.

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At Cleartherm, we pride ourselves on quality – we won’t settle for any less than the best.

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Welcome to Cleartherm Glass Sealed Units Limited

During 25 years of making high quality glass sealed units Cleartherm Glass Sealed Units has established itself as one of the leading manufacturers in the Midlands. Now based in Leicester after moving from a small unit in Barwell, with a £ I million + investments in state of the art glass toughening and automated line facilities means we can manufacture the highest performance sealed units incorporating award winning Super Spacer® warm edge technology making it easy to achieve a high energy rating for your windows.

We promise customers consistently high quality insulated glass units delivered on time, including gas filling as required. We provide comprehensive marketing support to help our customers sell more windows.
Cleartherm Glass Sealed Units provide the most advanced, thermally efficient sealed units at no extra cost, compared to competitor’s standard units, still manufactured with highly conductive conventional aluminium spacer bar.

"Always satisfying customers' needs"

Cleartherm Partners