Poor mobile reception indoors? Here is how to fix it
Outside you have full bars, but inside your calls drop. Poor mobile reception is a common problem in offices and commercial buildings. Usually your phone is not the cause. The building is.
Poor mobile reception in an office building: a common problem
A call that drops in the meeting room. No mobile data in the canteen. A two-factor code that never arrives at reception. Poor mobile reception is more than an annoyance: it costs time, and sometimes customers.
Remarkably, the problem occurs mostly in new and well-insulated buildings. The very measures that make a building sustainable also block the signal from mobile networks. On this page you can read what causes it, how to investigate it and which solutions are available, for tenants and for owners.
Why reception fails indoors
Insulating glass
HR++ and triple glazing have a thin, invisible metal coating that keeps heat in. That coating also strongly weakens the mobile signal.
Concrete and steel
Thick concrete floors and walls, steel structures and metal facade panels block the signal. The deeper you are inside the building, the weaker it gets.
Basements, car parks and lifts
Almost no signal from outside reaches underground spaces and lifts. Without an indoor system, there is hardly ever any reception there.
The building's location
A distant mast, tall buildings nearby or many people in one place already weaken reception outside. Indoors, you notice it first.
Investigate first
How to find out what causes the poor reception
Test another device
Try a different phone or put your SIM card in another device. If reception is much better, the phone is the problem, not the building.
Compare providers
Ask colleagues with a different provider about their reception. Sometimes one network has much less coverage indoors than another.
Measure room by room
Walk through the building and check the reception in each room. A simple app on your phone is enough. Pay attention to meeting rooms, the canteen, the stairs and the basement.
Write it down
Note where and when it goes wrong, and with which provider. With that information, the landlord, the provider or a specialist can help in a targeted way.
How to improve the mobile signal in a building
| Solution | Who it suits and what you arrange |
|---|---|
| Wi-Fi calling | Suitable for everyone, and usually the fastest solution. You switch it on in your phone settings. It only works if the Wi-Fi in the building is good and your provider supports it. |
| Repeater from your provider | For smaller spaces. Only allowed if your provider supplies and installs it. Ask your provider about the options. |
| Distributed antenna system (DAS) or small cells | For larger buildings. A specialist brings the providers' signal into the building through antennas. This requires a design and agreements with the providers. |
| Private mobile network | For large organisations with special requirements, such as hospitals or industry. Requires a specialist and a larger investment. |
Warning: do not buy a signal booster yourself
Many signal boosters and repeaters are sold online. Even so, you may not install one yourself. They use the providers' frequencies and can disrupt the network in the whole area. A repeater is only allowed with permission from your provider, and providers only give permission for devices they supply and install themselves. Without permission, the Dutch Authority for Digital Infrastructure (Rijksinspectie Digitale Infrastructuur, RDI) can impose a fine or an order subject to a penalty. Read the RDI rules (in Dutch).
Are you a tenant? Six questions for your landlord
Ask these questions before you sign, or if you are having trouble with poor reception now.
- How good is the mobile reception indoors? Has it ever been measured, and for which providers?
- Is there an indoor coverage system? For example a distributed antenna system, and which providers does it work for?
- Is the Wi-Fi good enough for Wi-Fi calling? In every room, including the meeting rooms and the canteen?
- What about the basement, the car park and the lifts? Is there reception there, for example for emergencies?
- Who fixes it if reception is poor? And who pays for a solution: the landlord or the tenant?
- Does the building have an IT-Label? Look it up in Find your IT-Label.
https://www.it-label.com/en/knowledge-base/mobile-coverage-in-buildings
Are you an owner? Include indoor coverage
A building with an excellent energy label can still have poor reception indoors. This matters more and more to tenants: they rely on mobile phones, two-factor authentication and apps. Poor reception is a reason not to rent, or to leave.
It is cheaper to arrange coverage in advance than to fix it afterwards. So pay attention to these points:
- For new builds and renovations: include indoor coverage in the design, just like power and ventilation. Space for cables and antennas is hard to create later.
- When choosing glass: ask the supplier about the effect on the mobile signal. Some treatments of insulating glass let more signal through.
- Talk to a specialist early: have an expert assess what the building needs in advance, and involve the providers.
- Measure and record: have the coverage measured, so you can inform tenants honestly and know where to improve.
How the IT-Label helps
The IT-Label assesses the digital quality of a building as a whole: the connection, the cabling, the Wi-Fi, the technical rooms and also the mobile coverage. The levels range from IT1+ PREMIUM to IT5 SHELL. This way, tenants and buyers know in advance what they get, and owners know where they can improve.
Look up a building in Find your IT-Label. Would you like to know how your building scores? With an IT-Label Pre-inspection, a Certified Partner assesses the building on site.
Frequently asked questions about mobile reception in buildings
How good is the reception in your building?
A Certified Partner assesses the digital infrastructure of your building, including the mobile coverage.
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