Are electric rooflights noisy when opening?

Context

Quieter than a bathroom extractor fan. Quieter than an electric garage door. About the level of a slow window blind motor.

It is audible in a quiet room, and nobody who has one mentions it a year later, because it is brief and it happens when you have deliberately pressed a button.

What makes it louder

Age and dryness. An actuator that has never been looked at gets noisier. The chain benefits from occasional light lubrication.

Strain. An actuator working against a heavy or binding sash sounds laboured. That is worth investigating rather than accepting, because it means the mechanism is under load it was not designed for.

Unsynchronised pairs. Two actuators on one wide sash that are not properly synchronised fight each other. That is both noisy and damaging.

Surface mounted housings can transmit a little more sound into the frame than recessed ones.

Bedrooms

The only place worth thinking about it, and the concern is usually automation rather than the motor. A rooflight programmed to close on a schedule or a rain trigger will do it at three in the morning if that is when it rains.

If that would wake you, set the automation to daytime only or rely on the rain sensor alone.

Rain on the glass

Worth separating. Most people asking this question are actually thinking about rain noise, which is a glass specification question rather than a motor one. Asymmetric or laminated glass reduces it and has to be specified at order.

Audible, and briefly

A chain actuator makes a low mechanical hum while it runs, comparable to an electric window in a car or a motorised blind. It takes fifteen to thirty seconds on a mains unit and thirty to sixty on a solar one, and then it stops.

In an occupied room you notice it. In a room with a television on, or a conversation happening, you generally do not.

What makes one louder than another

The sash weight. A heavier unit, particularly triple glazed, means the motor works harder and sounds it. This is one of several reasons we usually advise against triple glazing on an opening rooflight.

A dirty gasket. The commonest cause of a motor sounding strained. Grit and moss on the compression seal mean the actuator is fighting an obstruction on every cycle, and it gets louder as it gets worse. Cleaning it once a year removes the problem.

A dry chain. Light oil or a dry PTFE spray on the extended chain once a year keeps it quiet. Not grease, which collects grit and makes things worse.

Age. An actuator approaching the end of its ten to fifteen year life gets slower and noisier before it stops. That is useful warning rather than a fault.

Mounting. An actuator fixed to a frame that is not solidly seated transmits vibration into the structure. A properly fitted unit does not.

Where it might matter

Over a bedroom, if the window is set to close automatically at a scheduled time overnight. The sound of a motor running at three in the morning is not loud but it is unfamiliar.

The answer is to schedule closing for a sensible hour rather than the middle of the night, or to rely on the rain sensor rather than a timer.

Solar units are slightly quieter as well as slower, because the motor draws less current and runs more gently.

What is not the motor

Thermal ticking. A large glazed unit expands and contracts with temperature, and on a cold clear night after a warm day some installations make occasional small noises as the frame moves. That is normal and not a fault.

Rain on the glass is louder than any actuator, and if noise in a bedroom is the concern, acoustic laminate glazing addresses far more of it than the choice between manual and motorised does.

What to do if yours has got louder

Clean the gasket first. It is the commonest cause by a wide margin, and it is the one you can fix yourself in five minutes. Grit and moss on the compression seal mean the actuator is fighting an obstruction on every cycle, and it gets louder as it gets worse.

Then lubricate the chain where it extends from the housing, with light oil or a dry PTFE spray. Not grease, which collects grit and makes matters worse.

If it is still straining after both, the actuator is probably approaching the end of its ten to fifteen year life. That is useful warning rather than a fault, and it is a serviceable part that unbolts and is swapped in under an hour for a fraction of the cost of a new window.

Sounds that are not the actuator

Occasional ticking on a cold clear night after a warm day, which is the frame expanding and contracting. Normal, and it settles as an installation beds in.

And rain, which is louder than any actuator. If noise in a bedroom is the real concern, acoustic laminate glazing addresses far more of it than the choice between manual and motorised does.

Audible, and not loud

A chain or spindle actuator makes a low mechanical hum for the few seconds it runs. In a normal room it is comparable to a powered blind or a garage door opener at a distance: noticeable, and unremarkable.

Most people stop registering it within a fortnight.

When it gets louder, and what that means

A change in the sound is diagnostic and worth paying attention to.

Grinding, labouring, or a motor that hesitates before moving means it is fighting resistance: a stiff hinge, a distorted sash, a gasket that has swollen and grips, or debris in the path.

That resistance is what wears the drive, so a unit that has become noisy is telling you to look at the window rather than the motor.

Reducing it at specification

Where a rooflight is in or near a bedroom and will be operated at night, ask about the actuator type and the operating speed. Some run slower and quieter than others.

And keep the mechanism serviced with the lubricant the manufacturer names, sparingly, rather than general purpose oil which attracts grit and makes the problem worse.