I should have mentioned that yes, there are range extenders and they're probably fine, I just have no experience with them because they annoy the purist in me - one radio hop to the wired network ought to be enough for anyone. Plain repeaters are inexpensive and you can just stick one in, but effectively halve your wireless bandwidth. WDS by contrast is a relatively expensive technology which would require you to start from scratch and buy all the units from a single vendor. Again, I'd start by looking at the placement and performance of the ones you have.

And congratulations on moving in! When's the NetherPilg?

I'd forgotten about Powerline.

Yes, the power line systems work, but . . .
Beware if you have two or three phases for the house supply. It'll most likely cause much frustration should each end of the supposed circuit be on different phases.

Well, I said I'd consider it, there's quite a bit that can go wrong with them; they work best on the same circuit which might rule them out for a given installation; some stop working while an unshielded motor is running, such as a paper shredder or sink disposal or some below-spec appliance. It's usually good to buy from a business with a 30-day unconditional return policy so you can try these things out.

Before going that way the first thing to try is to just move your existing APs, try different channels, fiddling with the antennae, and then move on to testing out more powerful units. Newer 802.11ac units like the one I linked have multiple antennas and beamforming technology and are pretty good at getting a stable connection through walls. That one's Power over Ethernet as well so you don't to position it near a mains socket, though that raises the cost a little more since you need an injector to supply current. (Note also if you ever buy PoE network gear always use an injector that the manufacturer has tested, not whatever's cheap.)

Erm... it's a new house, and has a concrete structure, so there's at least 2 concrete walls/floors between the router (at dijk/road level) and the bedroom (lower floor). I guess we'll have the same problem when I get my top floor office working too. We've got one of the powerline adapter/access points, but I think it's too far away from the router - I need to use another socket. I'll start moving it about later this week when I get time. I don't need an enormous amount of bandwidth downstairs - I only listen to the radio in headphones in bed, that's all. Thanks for all the thinking.... I'll relay it to my technical consultant (aka the windy miller)