If your rooms feel chilly near the windows even with the heating on, the glass may be the problem rather than the frames themselves. Many homes in Cambridgeshire still have double glazing from the 1990s or early 2000s, made with plain clear glass and just air in the gap. Today’s Low-E glass units perform far better, and you can often get that performance without buying new windows.
What does “low-E” mean?
Low-E stands for low emissivity. It is a microscopically thin, invisible metal-oxide coating on one of the panes. It lets daylight through but reflects long-wave heat back into the room, rather than letting it radiate out through the glass.
Combined with an inert gas such as argon in the cavity and a “warm-edge” spacer bar, a low-E unit keeps the inner pane noticeably warmer. That means:
- less heat loss and lower heating demand
- fewer cold spots and draughty-feeling areas by the window
- less condensation on the inside of the glass
What is an A-rated glass unit?
Window energy ratings grade how well glass and frames balance heat loss against useful solar gain. An A-rated sealed unit combines low-E glass, gas fill and a warm-edge spacer. Ask your glazier for the specification, not just the letter.
Can I upgrade just the glass to Low E glass?
Yes, in most cases. Because we replace the sealed unit rather than the window, you keep your existing uPVC, aluminium or timber frames. The new unit is made to the exact size of the old one, so it fits the frame without any need for alteration. You can upgrade one problem window or the whole house, the choice is completely yours.
This makes particular sense when:
- the frames are in good condition, but the glass is old or misted
- you want warmer rooms such as bedrooms, but cannot justify full window replacement
- you are already replacing a failed unit, so the upgrade costs little extra
Can period homes have Low-E glass?
For single-glazed timber sashes, other options may suit better: slim Fineo vacuum glazing, which fits many original frames, or secondary glazing on the inside. Our blog post on Fineo may help you make an informed choice.
FAQs
Will low-E glass look tinted?
Not really, no. Modern coatings are virtually invisible in normal daylight.
Does it reduce noise too?
Standard low-E units help a little. For noise, ask about acoustic laminated glass.
How long does fitting take?
Most units are swapped in 30–60 minutes each.
Do you cover my area?
We replace units across Cambridge, Ely, Huntingdon, Newmarket and the surrounding villages.
We are a trusted, local glass and glazing company- but don’t just take our word for it; visit our Trust Index page to see for yourself. Thinking about warmer windows before winter? Visit our Cottenham showroom or ask us for a free quotation Contact us today!
