...I just have to ask, for friendly argument sake; Steve & Tom: why, when there is a problem with a doorbell, do you seemingly transform immediately into wireless doorbell salesmen?
Yes, I understand that a short in doorbell wiring can be frustrating, and often cannot be accessed for complete re-wiring, but, most of the time doorbell failures WILL be at accessible points like the bell, transformer, or the door buttons (which in my experience has been the #1 cause for failure). Beyond there, wires that are not subjected to motion rarely just decide to fail for no apparent reason.
12 years ago I bought the brick/slab home I'm still in today, which also has a "sucky" attic situation (you'd hope that if you had no access from below, you'd at least have a reasonable attic, but mine is a 2/12 "California/Contemporary" pitch, so it's tight quarters no matter what you do. Hey, I'm a contractor...I knew what I was getting into, but it still sucks),and it had no doorbell.
But, to install a wired doorbell, the only real thing I had to do which the average homeowner might not be readily equipped to do was drill through the studwall top plates within a narrow space beside the door, using my 5' long flexible-shaft drill bit, which paid for itself in no time.
Guys, I'm not against wireless bells, they have their place, BUT, I've got a wireless lighting control system...and guess what; every so often my wireless lighting control seems to activate my master bedroom light & fan, which has a totally separate remote control of it's own, of another brand, and of a very different year of manufacture.
Wireless technology is wonderful; don't get me wrong, but just like many other products, it is not yet foolproof. The "little old lady" who lived next door to me for many years never could get her wireless bell to work correctly, including my looking at it for her; what I found was that her steel siding interfered with the signal. I've also ran across problems where I was called in by a customer, and it turned out that the neighbor next door had a wireless remote system of some kind that would activate the customer's garage door, lighting, etc.
With all the possibilities of other "maybe" conflicts with other wireless remotes, etc. in today's homes, I will continue to build my new homes with hard-wired doorbells, with the wiring done in an accessible or replaceable manner, as I've always done in the past.