Need Wi-Fi upstairs, but router is in the garage

Hi everyone, Sorry if this is a very basic question, I’m completely new to home networking.

My father has a fairly large newer house. The ISP box/router is installed in the garage, and the Wi-Fi downstairs is okay, but upstairs it gets weak and sometimes devices just fall back to mobile data. There are RJ45 wall sockets in most rooms. I originally thought I could just buy a Wi-Fi repeater, plug it into one of those RJ45 ports upstairs, and it would “boost” the signal. After reading a bit, I’m starting to think that’s not exactly how it works.

What should I actually buy here? A repeater? Mesh? Access point? Something else?

Ideally I want one Wi-Fi name for the whole house and not something too complicated to manage. Thanks.

Don’t buy a wireless repeater if you have working RJ45 ports.

@GoodAfternoon_sun Agre. A repeater usually takes Wi-Fi in and rebroadcasts Wi-Fi out. That’s useful when you have no cable, but it’s not great if you already have Ethernet available.

What you want is a wired access point upstairs. Or a mesh system where the nodes support Ethernet backhaul.

Cable in. Wi-Fi out. Much better.

@GoodAfternoon_sun Okay, that already clears up.

First check where those RJ45 sockets actually go. In newer houses they usually terminate in a small network/communication cabinet somewhere near the ISP box. But sometimes they’re wired for phone only, or not patched into anything yet. You’ll probably need:

ISP router/box
small Ethernet switch
patch cables from the switch to the room ports
one or more access points plugged into the room ports

Don’t buy gear before confirming the wall jacks actually carry Ethernet.

Since the house is large, I’d avoid guessing where the AP should go. Take the floor plan and try NetSpot Planning. Mark the garage, walls, stairs, and the rooms with RJ45 sockets. Then place a virtual AP upstairs and see what kind of coverage you’re likely to get before buying random hardware. After installing the AP, do a quick survey/heatmap and check if the weak upstairs area is actually fixed. NetSpot won’t wire the house for you, obviously, but it’s useful for answering the question “where should the AP go?” instead of just picking the nearest outlet and hoping.

You have two good options: A normal access point upstairs and A mesh kit with wired backhaul

If your dad wants simple app management, a mesh kit with Ethernet backhaul may be easier. Eero, Deco, Orbi, UniFi Express-type setups, whatever fits budget. If you want more control and cleaner networking, get proper APs like Omada or UniFi.

Just don’t use wireless backhaul unless you have to. You have cables. Use them.

I found the small cabinet near the garage. There are several cables coming into it, but I don’t think anything is connected to them except the ISP box.So I probably need a switch there and then connect the upstairs room port to it?