On Mon, 22 Jan 2018 16:16:15 +0000, Another Dave
wrote:

My 1920s house is L-shaped and because of its geometry the Wifi signal
has to go outside and then back in to get to my study where all my
computers and cool stuff are.

The signal is effectively non-existent in the study so I used an old
router to extend the signal. Still no joy unless I put the extender in
the study.

A mate built a study in the back half of the garage / kitchen using
foil backed plasterboard and it acted like a Faraday cage. With an AP
in the room there was nearly no signal detected outside of it.

I'm forming the opinion that a metal foil moisture barrier is blocking
the signal though I have no evidence that there is one. The rest of the
house is fine.

Is this likely?

Yes. ;-(

Any suggestions?

Use a Poweline adaptor to put a hotspot in your study or carry on with
the router acting as a hotspot etc?

Cheers, T i m