The photograph here shows some double glazed sashes I have been working on for a property in Brighton.
I have glazed them with 14mm low-e sealed units. Thermal efficiency in windows is calculated as a U-value, with single-glazed windows having as value of around 5.6. Many different types of glazing unit are available each with its own U-value. As these sashes are to be installed into the original Victorian frames at the property, slim units (14mm) are used in this case. This reduces the U-value to around 3.0, and along with the draught-proofing system, will make a marked improvement to the drafty victorian sashes and offer some degree of sound insulation.
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A couple of photos showing the parting-bead and staff-bead used to draft proof the windows.
For more information on sash window refurbishment etc. see here.
Also, this week I was asked to replace some broken window glass and fit mirror film to the windows. I had not worked with this material before and had been warned it was a tricky job to do, here’s a picture of the finished job:
Tags: Double glazing, Windows, draft-proofing, mirror-film