I’ve set up a garden office, but it is a good 200mtrs from the house (right at the other end of the garden). The wifi signal just about reaches, but is so slow and patchy. Was just looking for some advice on what else can be done to extend the broadband down there, ideally without having to lay fibres or dig trenches.
Is this garden office connected to your house’s power circuit?
If so, you just need to invest in a powerline adapter: https://www.amazon.co.uk/s?k=powerline+adapter&ref=nb_sb_noss_1
Oliver has a good point - however powerline adapters can introuduce electrical noise that might interfere with your ping and cause you a bad Zoom/Teams experience etc. If you’re not afraid of paying a little bit more for a solid solution, you could look at a point-to-point wireless link.
Ubiquiti’s AirMAX is a really good product that features two transceiver units, one for the side of your house, and one for the side of your garden office. Some internal Ethernet routing in the house and the garden office will be required, but the end result it amazing.
You’d then just connect your router up to the house-end transceiver, then buy a mini-switch or a wireless AP with a built-in four port switch, and connect that at the office-end, a bit of config on the AirMAX, and you’re away!
I’ve provisioned and managed Ubiquiti products professionally for a number of years so I can vouch for them as being a good vendor for networking products!
I hope this helps.