Replacing heating films under a roof

Replacing is not installing

An existing installation imposes constraints a new job ignores: a layout already set, a substrate already drilled, circuits already run. The first task is to understand what was fitted before deciding what will be changed.

The diagnosis

A resistance measurement circuit by circuit locates the faulty zone. It is common for a single zone to be at fault while the rest of the installation works perfectly, which completely changes the scale of the job.

Access under the roof

That is what decides the method. An accessible loft allows work from above without touching the facing. An inaccessible loft means going through the room, and therefore taking down the finished ceiling.

What is kept

The supplies, the circuit labelling and often the framework. Those are the items that cost time, and keeping them reduces the operation to replacing components rather than reinstalling everything.

What is corrected while you are there

The plenum insulation. An old installation was often fitted with no reflector or with an open air gap. Since the ceiling is open anyway, this is the moment when the correction costs least.

The documentation to leave

Zone drawing, recorded measurements, references of the equipment fitted. The next person to work on it, in ten or fifteen years, will be in exactly the situation you have just been in, and that file will spare them the diagnosis. Three photographs before closing up are often worth more than a ten page manual.

Connection is set out on the dedicated page, and the choice of film on the heating films page.