Door Entry Intercom and Video Door Phone Installation and Repair in Porto

What Drives the Price: the Wiring, Not the Equipment

When someone asks for a quote to renew the intercom in their building, the first question isn't which brand they want. It is what cable is inside the walls. By far the largest part of the cost of a renewal is the labour of pulling new cable through old conduits, not the price of the monitors.

Buildings in Porto and Matosinhos built between the 1960s and the 1990s usually have 4+n systems: four wires shared by the whole riser plus one dedicated wire per flat. In a block of 12 flats that means 16 conductors running up the riser. If one of those wires has snapped or corroded, tracing the fault can cost more than all the equipment put together.

Modern 2-wire systems (two conductors carrying everything: audio, video, the call signal and power) solve that problem, which is why they are almost always the right proposal: two of the wires already in place are reused and the rest are left as spares. The job stops being a construction project and becomes a straightforward swap of handsets.

Audio Intercom, Video Door Phone or IP Video Door Phone

An audio intercom is the classic system: you talk and you buzz the door open. It is the cheapest to maintain and, in a building with many flats, it remains a sensible choice when the only goal is to get the entry phone working again.

A video door phone adds a picture. The real benefit isn't comfort, it is security: you see who is at the door before you let them in, and that changes things for people who live alone or have children who answer the door. On a 2-wire system, going from audio to video simply means swapping the handsets, with no building work.

An IP video door phone connects to the building's data network instead of a dedicated riser, and lets you answer the call on your mobile wherever you happen to be. It makes sense in houses, in alojamento local (holiday lets) and in offices; in an older residential block it is rarely worth it, because it requires structured cabling running up to every flat, which is already ITED telecoms work rather than a door entry job.

The Three Faults We See Again and Again

It rings but the door won't open. Most of the time the problem is neither the handset nor the street panel: it is the electric door strike or the power supply feeding it. A strike wears out over the years and starts to need more current than the supply can deliver, so it opens when the building is quiet and fails at the busiest times of day. Replacing the strike costs a fraction of replacing the system.

Poor sound or constant crackling. This is almost always the riser: a wire with degraded insulation touching another one, or a corroded connection in a junction box on one of the floors. On a 4+n system it spreads to every flat, and it is the classic sign that an upgrade to 2-wire is worth considering.

One flat has no sound while the others are fine. Here the fault is local: either that flat's handset or its dedicated wire. It is the cheapest scenario to fix, and the one behind most of the calls we receive.

Apartment Buildings: What to Take to the Owners' Meeting

Renewing a building's intercom is nearly always a decision for the condomínio, and most proposals reach the owners' meeting without the information needed to decide. What helps is to bring two separate quotes: one reusing the existing wiring and one with new wiring, each with its own price.

It is also worth settling two questions in advance, because they tend to stall the job halfway through: whether every flat will get the same monitor (usually yes, since it makes future maintenance simpler), and who is responsible for the handset inside each home, given that the equipment inside a flat belongs to its owner rather than to the condomínio.

We carry out the survey and deliver a written, itemised quote with the shared part separated from each flat's part, precisely so that it can be presented at the meeting without anyone having to reinterpret it. Owners' meetings in Portugal are held in Portuguese, so a clear breakdown also saves foreign owners from having to follow a technical debate in a second language.

In New Buildings, This Falls Under ITED

In a new building or a major refurbishment, the door entry infrastructure isn't a standalone job: it is part of the building's ITED design, which sets out the conduits, the telecoms cabinets and the space reserved for them. Installing outside that framework causes problems at inspection and again when the time comes to sell or let.

If your project is a new build, an extension or anything requiring planning approval, see also our page on ITED network cabling and telecoms, where we explain what the technical file must contain and when it is compulsory.

When equipment is replaced in existing buildings, which covers most cases, there is no design to submit and no inspection to arrange: it is ordinary electrical installation work.

Where We Work

We cover Matosinhos, Senhora da Hora, Leça da Palmeira, São Mamede de Infesta, Porto, Vila Nova de Gaia, Maia, Gondomar, Valongo and Ermesinde. In the buildings of downtown Porto and around Foz it is common to find installations more than thirty years old with narrow conduits, and in those cases a survey beforehand is what prevents surprises in the quote.

For a simple replacement we can usually sort it out during the visit itself, as long as the equipment is compatible. For building-wide renewals, the visit is used to survey the riser and count the flats, and the quote follows in writing.

Can I replace just my own handset without touching the rest of the building?

Yes, in the vast majority of cases. Each flat's handset works independently of the others, provided the new model is compatible with the installed system. What we need to know first is whether the building is 4+n or 2-wire and which equipment family it uses. Send us a photo of your current handset and of the street panel and we can usually tell you over the phone.

My intercom is very old. Can it still be repaired or do I have to replace everything?

It can be repaired more often than people think. Many old systems fail because of the electric door strike, the power supply or a corroded connection, all parts that can be replaced on their own. Replacing the whole system only makes sense when the riser wiring has deteriorated or when the condomínio wants to move to video.

Can we switch to video door phones without opening up the walls?

If the building is already 2-wire, yes: the street panel and monitors are swapped and there is no building work. If it is 4+n, usually yes as well, because the upgrade to 2-wire reuses two of the conductors already in place. Building work is only needed when the riser has no usable conductors, and that is picked up during the survey, before you commit to anything.

I want to answer the door on my mobile. Is that possible?

It is, with an IP system or with 2-wire equipment that has a network module. In a house it is straightforward. In a flat it depends on there being a data network reaching your home and on the condomínio accepting the change to the shared part, because the street panel is used by everyone.

Does the video door phone record? Are there legal implications?

Some models do record. As long as the device only shows the picture while a call is in progress, it is an ordinary door entry system. Once it records and the camera covers public or shared space, it is treated as video surveillance, with all the obligations that come with that, and in an apartment building it requires a resolution from the owners. We explain the difference before installing so that you can make an informed choice.

How long does it take to renew a building's system?

Reusing the wiring, a building of 8 to 12 flats is normally done in one to two working days, with the entry phone out of action for just a few hours. With new wiring it depends entirely on the conduits, and in that case the timescale is given after the survey, never before.

Do you work with condomínios and invoice the condomínio directly?

Yes. We provide a written, itemised quote with the shared part separated from each flat's part, so it can be presented at the owners' meeting. Invoicing then follows whoever made the decision: the condomínio for the shared part and the individual owner for anything inside their flat.