Networking 2 thick walled buildings

As said above, I have 2 building, my house and my office, they are about 25 meters apart, with a swtich in each building. We are getting a broadband connection into my office and I was going to share the connection with my house. Now I was thinking of networking my office and house wirelessly. I don't really have a clue what kind of kit I would need, I already have all my machines on a wired network and I was looking to bridge the 2 networks through my server. The server (which is in my office) is about 30 meters away from the swtich in the house and is seperated by a foot thick wall covered in books, a wooden wall + insulation, a brick wall and a door.
Does anyone know what kind of kit i would need todo this, i was thinking of maybe a wireless card in my server and an accesspoint connected to my switch in the house, any good?
Any help would be greatly appreciated

Two access points in bridge mode, with external antennas.

No chance of running cable?

well not really, because there is a garden and path between the 2 buildings and everyone else in the house dont like the idea. The shortest route via cable is about 50 meters I reckon because it has to go along and fence and along the gutter.
Thats why I though wireless networking was the way to go

[edit] if i used a pair of accesspoints with external antenna's then the distance is only about 20 to 25 meters. Also I would easily be able to place an accesspoint at a window in each of the buildings so there would be nothing obstructing