19th-century industrial
Secondary Glazing for Converted Mill
If you own a converted mill, the window problem is nearly always the same: enormous heat loss and street-level noise. Kelham Island, Neepsend and Attercliffe mill conversions came with the biggest and worst-performing windows in the residential market.
Why converted mill owners choose secondary glazing
Acoustic laminated glass is standard because most mill conversions sit on ex-industrial main roads.
Where the original Crittall is a listed feature, we specify slim satin-anodised profiles that match the black sightlines.
Multi-panel horizontal sliders let us cover openings up to 3 m wide in a single system.
Recommended: Soundproofing
cut outside noise by up to 80%
45–54 dB reduction with a 100–150 mm cavity
The acoustic gain comes from air-gap decoupling — a 100 mm cavity between the existing pane and the secondary pane detunes the resonant frequencies that carry traffic noise into a room.
Local reference points
- Era
- 19th-century industrial
- Typical window
- large steel-frame factory glazing
- Top problem
- enormous heat loss and street-level noise
- Recommended service
- Soundproofing
- Recommended product
- horizontal sliders
- Performance
- 45–54 dB reduction with a 100–150 mm cavity
Recent installs nearby
Kelham Island loft conversion
Four large steel-frame factory openings sealed with slim satin-anodised horizontal sliders. Post-install U-value 1.87 W/m²K.
Nether Edge Grade II sash retrofit
Six original box sashes fitted with balanced vertical secondary sliders — full listed-building consent secured in six weeks.
Ecclesall Road bay-window sound retrofit
Three-panel horizontal sliders across a 3.2 m Edwardian bay — Rw measured at 47 dB post-install.
Ready for a written quote?
Send us the opening dimensions or a photo and we'll come back within one working day.
Common questions
Can Low-E glass be combined with acoustic laminated?
Yes — most heavy specifications combine both, so you get acoustic gain and thermal gain in the same install.
Do you install in flats and communal buildings?
Yes — the install is entirely inside your flat, so freeholder consent is usually straightforward and window-cleaner access to the primary window is unaffected.
What glass thickness do you recommend for main-road noise?
6.4 mm laminated on the secondary as standard, or 6.8 mm where the road carries heavy commercial traffic.
How is the quote calculated?
We survey and template every opening on site, then quote in writing per opening — no per-square-metre pricing that hides oversize charges.
Does it help with train and tram rumble?
It's very effective — the low-frequency energy is absorbed by the air-gap decoupling. A mismatched pane thickness widens the acoustic dip that train rumble usually punches through.
Next step for converted mill owners
Send us photos of one or two windows and we'll come back with a written quote and a spec sheet you can compare against replacement double glazing.