Can a VELUX be upgraded to quieter glass?

Noise reaches a loft room through the thinnest part of the roof, and in a roof window that is the glass. The frame, the flashing and the tiles around it do much less.

A standard double glazed unit is two panes with a sealed cavity between them. It keeps the heat in and the weather out, and it lets through more sound than people expect, especially rain and the lower hum of aircraft and traffic. Two panes of equal thickness tend to move together when a sound wave strikes them, which is a weakness in a room where the ceiling is the glass.

A laminated acoustic pane works differently. Two sheets of glass are bonded with a sound damping interlayer. That interlayer takes energy out of the vibration instead of passing it on, and it also holds the glass together if it breaks, which is a safety advantage over a roof. Part K of the Building Regulations covers glazing in places where people could be hurt, such as doors and low panes, and laminated glass is the usual answer overhead.

So the upgrade is a change of one component. You are not rebuilding the loft. You are swapping the pane that carries the sound for one that carries less. Our page on glazing options for a quieter loft compares the choices in more detail.

There is more than one route, and the right one depends on the window you have today. Each of the three below leaves the roof covering around the frame alone.

1. A new sash in the existing frame. If the frame is sound and the current range still offers a matching sash with the glazing you want, the moving part is swapped and the frame stays. It is the least disruptive route. Whether it is possible depends on the model, and whether a VELUX sash can be replaced without changing the frame is covered on its own page.
2. A new window in the same opening. The old frame comes out and a new one of the same code goes in, with a new flashing and collar. The rafters and the opening are unchanged, and the lining inside usually stays. This is the route when the frame is tired or the model is no longer supported.
3. A new window of a different size. This reopens the roof structure, because the opening has to be altered. It is chosen when the room needs more light, not only less noise, and it is a larger job.

The second route is the one most homes end up with, because a window old enough to need a quieter pane is usually old enough for its seals and its frame to be tired as well. The first route is worth asking about, because it saves the most disruption when it is available.

Everything about the upgrade is easier to judge once you can see the two sides of the job at once.

Keeping the frame and flashing avoids lifting tiles, which shortens the job and keeps the roof closed for less time. Replacing them brings a fresh weather line and new seals, and gives the thermal performance of a current window.

The seals deserve attention either way. A quiet pane set in a tired gasket still lets sound round its edge, because sound finds the smallest gap. When the window is replaced, new seals come with it. When only the sash is swapped, the new sash carries its own seals, and the frame side is checked at the same visit.

Part L of the Building Regulations applies when a window is replaced, because a new window has to meet current thermal limits. A replacement unit from the current range is made to meet them, and we fit to current regulations and handle the Building Control notification where the work is notifiable.

The glazing on your window is recorded on its plate, and the plate is where the decision starts. It tells you the size, the model family and the glazing type it was built with.

With that information, current VELUX data shows which glazing options are made for your frame. You will find letters in that code which describe the glazing and the opening type, and our page on VELUX GGL, GPL and GGU explains what they stand for. If the plate is missing, where to find it on the window is worth a look, and if it has gone completely there is a way to find your size by measuring.

Two other items are worth checking. The pitch of the roof limits the window types you can use, because each one has a range. And a window that sits over a bed needs the pane chosen for night noise, where one over a landing may not. The written quiet spec that comes with every quote records which noise we listened for and which glazing we propose in response.

The honest test is how you use the room. A loft bedroom under aircraft routes or beside a busy road gains the most. A storeroom gains very little.

Think about the hours the noise arrives. Early departures and late arrivals reach a bedroom when you most want silence, and rain on the glass reaches a loft office during calls. If either describes your room, the pane is where the money does most good. If the window is also misted or has lost its seals, you are replacing it anyway and the quieter pane costs little extra thought. The costs page explains in general terms how glazing choices move the price.

A window that has fogged between the panes has a failed seal, and that is a replacement job in its own right. Our service for misted and failed rooflight replacement covers that case, and it is a natural moment to move to an acoustic pane.

The fitting itself is straightforward for a window of this kind. A new sash can often be completed in a single visit, and a new frame in the same opening takes a little longer, because the roof covering has to be opened and closed again. We protect the room below and make good inside at the end. To ask about your own window, use the quote form, and the parent page on VELUX window installation in Crawley shows the rest of the service.

Will a quieter pane make the room silent?

No pane removes every sound. A laminated acoustic pane reduces what comes through the glass, and sound that arrives by other routes, such as gaps round the frame, is dealt with by fresh seals and a careful fit.

Can I keep my existing frame?

Sometimes. If current data lists a matching sash with the glazing you want, and the frame is sound, only the sash changes. Otherwise the frame is replaced with the glass.

Does the roof covering have to come off?

A sash swap leaves the covering in place. A new frame means lifting the tiles around the window, then relaying them into a new flashing, which is done in one visit for a single window.

Is acoustic glass stronger?

Laminated glass is made to hold together on breakage, which is why it is used overhead. It is chosen for that safety as well as for the sound, and the two benefits arrive together.