Why Your Wi-Fi Is Bad in an Old House (and How to Actually Fix It)

If you live in a house built before about 1960 in Burbank, Glendale, Pasadena, Eagle Rock or Los Feliz, and your Wi-Fi dies halfway down the hall, the problem is probably not your router. It's your walls, and specifically what's inside them.

The metal in your walls

Before drywall became standard in the 1950s, interior walls were built as lath and plaster: thin wooden strips (lath) nailed across the studs, with wet plaster pushed through the gaps to key into place. Fine on its own — wood and plaster attenuate Wi-Fi but don't block it.

The problem is metal lath. From the 1920s onward, expanded metal mesh was widely used instead of or alongside wood lath, especially in bathrooms, kitchens, around arches and curved details, and in Spanish and Mediterranean homes throughout Southern California. Exterior stucco was almost universally applied over wire lath too.

A grid of metal mesh in a wall is, electrically speaking, a Faraday cage. It's very good at reflecting and absorbing radio waves. It's particularly effective against 5 GHz Wi-Fi, which is exactly the band that carries the speed you want.

The practical consequence: in a 1935 Spanish home in Glendale, a single wall can cost you 20–30 dB of signal. Two walls and you're done. No consumer router made, at any price, transmits enough power to punch through it — and legally none can, because the FCC caps transmit power.

The other four culprits

Router placement

Your router is wherever the cable or fiber entered the building — a front closet, the garage, behind the TV, in a corner. Wi-Fi radiates roughly spherically. If the router is at the front corner of the house, half your signal is heating the neighbor's driveway. Even moving it to a central, elevated, unenclosed spot can transform coverage, and it costs nothing.

Wireless extenders

Here's the part the packaging doesn't say. A wireless repeater has to receive a packet and then retransmit it on the same radio. That halves available throughput — before accounting for the fact that it's operating in a weak-signal area to begin with. Then it creates a second network that your phone clings to at two bars long after you've walked back toward the router.

Extenders extend coverage, in the sense that you have bars. They do not extend usable speed. If you have one and things got worse, that's why.

Channel congestion

In apartment corridors in NoHo, Hollywood or Downtown Glendale, a scan can show forty or fifty networks. The 2.4 GHz band has only three non-overlapping channels. Everyone is shouting in the same room. The answer here is a channel plan and moving devices to 5 GHz or 6 GHz where the air is quieter — not more power.

The internet service itself

Sometimes it genuinely is the ISP: a corroded coax splitter, a failing modem or ONT, a plan that can't support four simultaneous 4K streams, or an upstream problem. This is worth testing properly — plug a laptop into the modem with a cable and run a speed test. If the wired result is bad, no amount of Wi-Fi work will help.

The four fixes that actually work

Fix 1: Move the router (free)

Central, high, out in the open, away from metal, mirrors, aquariums and the microwave. If the modem can't move, a single Ethernet cable or MoCA adapter lets the router move even when the modem can't. Worth trying before spending anything.

Fix 2: Mesh with wired backhaul (the right answer)

Two or three Wi-Fi units placed where coverage is needed, each connected back to the router by an Ethernet cable rather than talking to each other wirelessly. Each unit transmits at full strength into its own area, and the connection between them is a cable, so nothing is halved.

This is what "we fixed the Wi-Fi and never thought about it again" looks like. It costs more because someone has to run cable through an attic or along an exterior, and it is worth every dollar.

Typical cost: $380–$650 in labor for three nodes including the cable runs, plus hardware at cost.

Fix 3: MoCA over existing coax (the clever cheap one)

Most Burbank and Valley homes built or updated between about 1980 and 2010 have coaxial cable run to several rooms for cable TV. MoCA adapters turn that coax into a high-speed wired network — typically 1–2.5 Gbps — with no new cable to run.

If you have coax outlets in the rooms where you need coverage, this is often the cheapest possible path to a proper wired backhaul. Adapters are about $60–$120 a pair.

Fix 4: Tri-band mesh with dedicated backhaul (when nothing else is possible)

If you rent, or the house genuinely can't be cabled, modern tri-band mesh systems reserve one radio exclusively for node-to-node traffic. That solves the halving problem, though it's still fighting the same walls. It's a legitimate second-best and much better than an extender.

A worked example

A 1938 Spanish house in Glendale, about 1,900 square feet, single story, plaster over metal lath throughout, router in the front hall closet where the coax comes in. Bedrooms at the back get 3–8 Mbps and drop constantly. Owner has already bought two extenders and a $380 router.

What was done: Site survey confirmed roughly 25 dB of loss per interior wall. Ran two Cat6 drops through the attic — one to the living room, one to the back hall. Mounted two ceiling access points, put the router in bridge mode, removed both extenders, set a single network name with proper roaming.

Result: 400+ Mbps everywhere in the house including the back bedrooms and the patio. Total: about $520 in labor plus $290 in hardware.

The two extenders and the expensive router had cost more than the fix.

What to check yourself, right now

• Plug a laptop into the modem with an Ethernet cable and run a speed test. That's your ceiling. If it's low, the problem is upstream of Wi-Fi entirely.
• Walk the house with a Wi-Fi analyzer app (free on Android; on iOS use Apple's AirPort Utility with scanning enabled, or just note where the bars fall off). Anything below -70 dBm is functionally unusable.
• Count competing networks. More than fifteen strong ones means congestion is a real factor.
• Look for coax outlets in the rooms with bad coverage. If they exist, MoCA is probably your cheapest fix.
• Check whether your router is in a closet, a cabinet, or behind a TV. All three are bad. Move it and re-test before buying anything.

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Need this done rather than explained? Call (747) 344-7727 or request a free estimate. Serving Burbank and 25 miles around it.