If his Wireless Access Point (WAP) worked in his house and then suddenly stopped, it would point either to a failed WAP or someone simply switching off the WAP element in the router configuration.
If the WAP never worked in his house, it could be that the structure is too dense for the wifi signal to penetrate - follow airborne_artist's advice and get the laptop right beside it.
You could also try bringing the unit to your house to test.
But my bet is failed / switched off.
SD