How Building Materials Affect Mobile Phone Signal?

A strong and reliable mobile signal has become essential in every aspect of modern life. Whether people are at home, at work or out and about, they’ve come to expect a high-quality cellular signal that allows them to stay connected wherever they are. However, many of the most common building materials can significantly reduce mobile signal leading to poor indoor connectivity. So, which building materials have the biggest impact on signal strength?

Metal, particularly steel, causes the most disruption to mobile phone signal strength. Other common building materials that can significantly reduce signal quality are Low Emissivity Glass and concrete. However, most building materials cause some disruption to mobile signals, including insulation, drywall, brick and tiles.

Continue reading to learn more about the effect that these different building materials have on signal strength and the most effective solution to poor indoor connectivity.

Which Building Materials Affect Mobile Phone Signal?

A wide range of common building materials can block phone signals leading to poor indoor connectivity.

Glass

Single glass panels allow radio waves, and therefore phone signals, to pass through with minimal disruption. However, double-glazing can have more of an impact on mobile phone signals due to the layer of air trapped between the two panels.

Low-Emissivity Glass

Low-E Glass (Low Emissivity Glass) has a thin, microscopic coating which reflects thermal energy back into the room helping to improve a building’s thermal efficiency. However, this reflective nature means that Low-E Glass is much more disruptive to mobile phone signals. The reflective coating reflects a portion of the radio waves away from the building, reducing indoor connectivity.

Insulation

Insulation materials, such as fibreglass, generally have a minor impact on phone signal strength. This is because fibreglass insulation is fairly light, so it allows phone signals to pass through without much interference.

Plasterboard/drywall

Plasterboard or drywall generally causes some disruption to mobile phone signals, but this is usually minimal as it’s fairly light. However, if there are multiple layers of drywall, it can cause more serious disruption.

Tiles

Both ceramic and porcelain tiles can moderately block mobile phone signals, with porcelain tiles causing slightly more signal disruption due to their density. This causes the tiles to absorb some of the electromagnetic energy from phone signals.

Wood

Most wood materials, such as plywood, only moderately affect mobile phone signals. Typically softwoods are less dense than hardwoods, so these have less of an effect on mobile signal strength.

Brick

Brick is one of the materials that has the most effect on mobile connectivity. Bricks are dense and solid meaning they can absorb radio waves reducing mobile signal strength. Hollow bricks or brick veneers have less of an impact on mobile signals than traditional clay bricks which can cause significant signal loss.

Concrete

Because of its density, concrete can significantly reduce indoor mobile phone signal. In particular, reinforced concrete, which contains steel rebar or mesh, can strongly reduce connectivity. The high density of concrete means a significant portion of the electromagnetic energy is absorbed, which prevents the radio waves from passing through the concrete. 5G signals have higher frequencies which mean they are more likely to be blocked by concrete structures or walls.

Metal

Metal, such as steel, is the building material that most strongly affects mobile phone signals. Because metal conducts electricity, this material can absorb and reflect electromagnetic waves significantly reducing signal strength. Solid sheets of metal, used in roofs or walls, can almost entirely block mobile signals because the signals are reflected off the surface in different directions.

Metal enclosures, called Faraday cages, are used to deliberately block mobile signals so it makes sense that using this material in the construction of ordinary buildings will reduce phone signal strength.

The Impact of Building Materials on Mobile Signal Strength

Mobile signal strength is measured in decibels milliwatts (dBm). A good mobile signal strength is -60 to -70 dBm while a poor signal might be in the range of -85 to -95 dBm. -120 dBm means that there is no signal at all and you are in a signal dead zone.

Read our blog, ‘How Signal Dead Zones Affect Your Business?’, to learn more about signal dead zones.

Have a look at the table below to view the signal loss for the most common types of building materials.

Building material	Signal Loss (measured in dBm)
Single pane glass	2
Fibreglass insulation	2
Drywall/plasterboard	2
Plywood	6 – 9
Ceramic Tiles	3 – 10
Brick	8 – 16
Concrete	8 – 28
Low-E Glass	24 – 40
Metal	32 – 50

Summary

• Low signal interference (2-5 dBm): Materials like glass, drywall and fibreglass insulation allow mobile signals to pass through with minimal reduction.
• Moderate signal interference (5-15 dBm): Plaster, brick and wood cause a moderate reduction in signal strength.
• Significant signal interference (15-50 dBm): Concrete, Low-E Glass and metals (like steel) can cause a significant reduction in mobile signal strength, with steel being the material which most effectively blocks cellular signals.

How Do These Building Materials Affect Phone Signal Strength?

Common building materials affect mobile phone signals by absorbing, reflecting or blocking the electromagnetic waves that carry the cellular signal. These waves are usually in the radio frequency range. Each material will interact with the electromagnetic waves slightly differently depending on its density, composition and conductivity. These interactions ultimately lead to signal attenuation or loss.

Increase Your Mobile Signal Strength with NetCov

If your commercial building or workplace is struggling with poor mobile connectivity, the only reliable way to improve signal quality is to install a high-performance signal booster.

At NetCov, we specialise in creating tailored signal-boosting solutions that work for your business. Whatever building material is interfering with your signal strength, we can install a signal booster that will ensure you receive a high-quality and seamless phone signal throughout your building. All our boosters are Ofcom-approved, so you can be sure you’re fully compliant with all UK legislation.

Contact our team today to see how we can solve your connectivity issues or book your free consultation to get started.