In-building mobile signal solutions
Delivering better communications and faster data speeds to your business
Why mobile signal fails inside buildings
Coverage maps show signal outside. Inside, modern construction blocks most of it, so calls drop, apps stall and people walk to the window to make a call. It affects staff, visitors and customers on every network.
Coated glass
Energy-saving windows reflect signal back outside.
Concrete and steel
Thick walls, cores and metal cladding stop signal getting in.
Below ground
Basements, car parks and plant rooms often have no signal at all.
Calls need 4G
Since the 3G switch-off, calls run over 4G, so weak 4G means dropped calls.
Outdoor signal, brought inside
- CaptureA donor antenna on the roof picks up the strongest signal we measured during the survey.
- Clean and amplifyA Nextivity CEL-FI unit boosts that signal without interfering with the network or your neighbours.
- SpreadSmall indoor antennas cover every floor, so phones get full signal wherever people work.
Solutions for your network, building and area
Every building is different. Start with your network, your type of building or your area.
By building
From survey to full signal, usually in weeks
One team does the whole job, so there is one point of contact from the first call to ongoing support.
- 1SurveyWe measure signal on every network, inside and out.
- 2Design and quoteAntenna plan and a fixed price.
- 3InstallOur own engineers, with minimal disruption.
- 4Test and hand overWe prove the coverage before we leave.
- 5MonitorOptional 24/7 signal monitoring. Learn more
Only legal boosters
Many boosters sold online are illegal in the UK and can disrupt the network for everyone nearby. We install only Ofcom-compliant, operator-approved systems.
3-month money-back guarantee
If your system doesn’t meet the coverage targets we agree before any work starts, you get your money back. No small print.
Mobile signal before and after our installations
We survey every building before and after installation with our own survey app. These are real readings from recent projects.
O2 network
O2 network
O2 network
Vodafone network
Average signal strength (RSRP) across each surveyed floor. Usable means better than −107 dBm, the level phones need for reliable calls over 4G.
Recent projects
In-building signal: common questions
What is an in-building mobile signal solution?
A system that takes mobile signal from outside and spreads it inside your building, so calls and data work in every room. We use Nextivity CEL-FI equipment, from single units for one floor to multi-network systems for whole campuses.
Are signal boosters legal in the UK?
Yes, if they meet Ofcom’s rules. Since the Wireless Telegraphy (Mobile Repeater) (Exemption) Regulations 2018, approved single-network boosters can be used without a licence. Multi-network systems need the networks’ consent, which we arrange. Unapproved boosters bought online are illegal, and Ofcom can act against anyone using one.
Which networks can you boost?
EE, O2, Vodafone and Three, plus every provider that runs on them, such as BT, Sky, Tesco Mobile, giffgaff and Virgin Media. A multi-network CEL-FI QUATRA system covers all four networks at once.
Will it work if there is no signal outside?
A booster needs some outdoor signal to work with. The survey finds the strongest signal around your building. If there is none, we will tell you and suggest the alternatives.
How do we know it keeps working?
Every system is tested at handover. For ongoing peace of mind, our Mobile Signal Monitoring service measures signal on every network around the clock and alerts us if it drops.
Ready for full signal in your building?
Book a free signal assessment and get a design and fixed quote.