Cellular Internet in Metal Buildings, Basements, and Mobile Homes

Radio signal and metal have a simple relationship. Signal arrives. Metal says no. Signal leaves.

That is a problem if you live or work inside something made of metal, under something made of concrete, or in a home with a metal skin. Metal shops, pole barns, basements, and mobile homes are the three hardest places to run a cellular modem. They are also very common places to need one. This guide covers why each is difficult and the placement moves that work.

Why these buildings are hard

Cellular signal passes through materials with different amounts of loss. Wood and drywall barely slow it down. Plain glass is the easiest path. Brick and concrete take a real bite. Metal reflects it almost completely.

A building wrapped in metal, or buried in concrete and earth, turns the inside into a quiet zone. The signal outside may be excellent. It just cannot get in. The fix is always the same idea: find the gap in the armor and put the modem there. The background is in what affects cellular signal.

Metal shops, pole barns, and steel buildings

Steel siding plus a steel roof is about as signal proof as ordinary construction gets. Foil faced insulation on the inside makes it worse.

Where the gaps are:

• Windows. Even a small one. Put the modem on the sill or a shelf right beside it.
• The office. Many shops have a framed office with a real window. That is usually the best spot in the building.
• Doors that stay open. A roll up door that is open during work hours is a very large window. A shelf near the door, up high, often works well while you are working.
• Skylights and translucent panels. Light panels in the roof or upper walls are not metal. A shelf beneath one can pick up signal from above.
• Walk doors with glass. Less ideal than a window, better than a wall.

What to avoid:

• Steel cabinets, gang boxes, and tool chests. If it needs to be locked up, use a plastic enclosure near a window.
• Spots beside welders, compressors, and generators. Electrical noise and vibration are both bad for it.
• The middle of the building. It is the farthest point from every gap.

If the modem works best in the office but you need internet on the shop floor, that is a wifi reach question. Wifi also dislikes metal, so keep the office door open and the path as clear as you can. On the Business plan, the modem's Ethernet port lets you run a cable to equipment that needs a wired connection.

Basements

A basement is surrounded by concrete and soil on most sides, and the tower is somewhere above ground level. Signal has to come down through the house or in through a tiny window.

Best moves, in order:

1. Do not put the modem in the basement. Seriously. Put it on the floor above, near a window, and let the wifi reach down. Wifi passes through a wood floor far more easily than cellular signal passes through a foundation.
2. Place it near the top of the basement stairs. A shelf on the main floor close to the stairwell gives the wifi an open path down.
3. If it must be in the basement, use the window well. A basement window, even a small one at ground level, is the gap. Put the modem as close to it and as high as you can.
4. Choose the walkout side. In a walkout basement, the wall with the door and full windows is above grade. Treat it like any ground floor room.

For basement apartments where upstairs is not yours to use, the window is everything. Test each one. If none of them gets a usable connection, the building may be the limit, and the 30 day return exists for exactly that.

Mobile and manufactured homes

Many mobile homes have metal siding, a metal roof, or both, and older ones often have metal under the floor too. Newer manufactured homes with vinyl siding and shingle roofs behave more like regular houses.

What works:

• Windows, always. Mobile homes usually have plenty. Pick one on the side facing the nearest town or highway.
• Height. The top of a bookshelf or an upper kitchen cabinet next to a window.
• The ends of the home. End walls often have large windows and a clearer view than the long sides, which may face a neighbor's home a few feet away.
• Away from the kitchen appliances and the furnace closet. In a narrow floor plan, everything is close to something metal. Find the window farthest from all of it.

In a park where homes are close together, your neighbor's metal home can block one side of yours. Test windows on both long sides before you decide.

The ten minute test, hard building edition

The standard test from our modem placement guide works here with one change: test more spots, because the difference between them will be much bigger than in a wood frame house.

1. List every gap: windows, glass doors, skylights, doors that stay open.
2. Turn the modem on at the first one. Give it a minute or two to connect.
3. Standing next to it, load the same video or page on your phone over the modem's wifi.
4. Move to the next gap. Repeat.
5. Keep the winner, even if it is not where you pictured the modem living. Run an extension cord if you need to.

In a metal building, one spot is often dramatically better than all the others. Finding it is the whole job.

Check the outside first

Before you blame the building, find out what the building is blocking. Step outside with the modem on battery, or with a phone, and check the connection in the open air next to the building.

• Good outside, bad inside: the building is the problem, and the gap hunting above is the fix.
• Bad outside too: the location has weak signal, and no window will fix that. See our rural internet comparison for when another type of service is the better tool.

Things that do not work

• Putting the modem outside. It is an indoor device. Rain, dew, and heat will damage it, and water damage costs you the deposit. Get it to a window instead.
• Foil, pans, or homemade reflectors. You are adding metal to a metal problem.
• Signal booster apps. Software cannot change what your walls are made of.
• Leaving it in the first spot you tried. In these buildings the first spot is almost never the best one.

Try it without the risk

Hard buildings are exactly why we do not ask for a commitment. The plan is month to month, there is no contract, and the only thing we hold is a $100 refundable deposit. If you test every gap and nothing works, cancel from your account, return the modem within 30 days with the prepaid label, and the deposit comes back. The Coverage page is upfront that service is not guaranteed at any specific location.

Frequently asked questions

Will it work in my metal barn?
Maybe. It depends on the signal outside and the gaps in the building. Put it near a window, a translucent panel, or a door that stays open, and test.

My basement office has no windows. Any options?
Put the modem on the floor above, near a window, as close to directly overhead or to the stairwell as you can. Let the wifi come down to you.

Does a metal roof alone cause problems?
Less than metal walls. Signal mostly arrives from the sides, through windows. A metal roof with ordinary walls and windows is usually fine.

Do energy efficient windows block signal?
Some have a metallic coating that does. If a window spot underperforms, try a different window or an older pane of glass, such as a door or garage window.

Is a job trailer the same problem?
Yes, with extra steel. Our job site internet guide covers trailers specifically.

The bottom line

Metal, concrete, and earth block signal. Every hard building still has a gap: a window, an open door, a light panel, the floor above. Find it, put the modem there, up high, and test before you settle.

If you have not ordered yet, How it Works shows the whole process. The modem ships free, and the test is ten minutes with your own phone.