Secondary Glazing for Home Offices

Noise-cancelling software handles steady background hum reasonably well but fails on the impulsive events London specialises in — a siren, a pneumatic drill, a motorbike. Those get through, and they get through loudly.

Reducing the source level at the window by 25-30dB removes the problem at its origin rather than relying on processing to hide it.

A working target of around 40dB gives you a room where the background is a floor rather than a series of events. That is what makes deep work possible: the brain stops orienting to each new sound.

Home offices are frequently the coldest room in a London house — a rear return, a box room, or a loft with a single-glazed dormer. The thermal effect of secondary glazing is often the change people notice first, particularly the removal of the cold downdraught if you sit at a desk in the window.

A home office has a second listener: everyone on the call. Your microphone picks up the road outside at a level your brain has learned to filter out but noise suppression has not, and the result is the clipped, gated audio that makes remote meetings tiring. Reducing the level at the window is the only intervention that fixes it at source.

Speech-band frequencies — roughly 250Hz to 4kHz — are where the damage is done, and that is the band secondary glazing handles best. A sealed panel with 6.4mm or 10.8mm laminate and a 100mm cavity typically removes the intelligible content of street conversation and the hiss of passing traffic entirely, which is what microphones are most sensitive to.

Adding a second hard glazed surface slightly increases reflectivity in the room, and in a sparsely furnished home office that can make your own voice sound harder on a call. It is easily managed — a rug, curtains or a bookcase on the opposing wall — but we mention it at survey because it is the one side effect people notice and nobody warns them about.

Where the office is also a bedroom or spare room, we specify for the noisier of the two uses. It is cheaper than treating the same window twice.

The build-ups we use for home offices come straight from our commercial projects work in London offices and meeting rooms: laminate glazing, continuous compression sealing and a cavity sized to the reveal, specified against a measured level rather than a guess.

For a permanently occupied workspace the thermal side matters too. A sealed secondary layer removes the draught at desk height that makes a period-property office uncomfortable in winter, and low-emissivity laminate is worth considering in a room heated eight hours a day.