I am helping my nephew fix up the wiring in a log house. A lot of the wiring in not according to code, so I am going to have to go a little at a time. First the wiring for the smoke detectors are not right. Whoever done the wiring, just pulled 2 wire to the detectors instead of 3 wire. By the way the walls have already been closed in
But anyway, he has a smoke detector wired in the peak of the house, which will very hard to fix(no access), he also has one upstairs in the "open area" at the top of the stairs. My question: Since the code only says each level must have one, cannot the one in the peak be done away with, and turned into a light box, and use the one that is accessible to meet the requirements of the code? I know the requirements for the bedrooms. They can be fixed using wiremold etc. Is there any special thing about log homes that anyone is aware of, about the "peak" of the roof area? The area that I'm speaking of is totally open at the top of the stairs. Thanks Steve

First of all, details as to detector placement are usually found in your local building code; detectors also come with some pretty comprehensive instructions. There is certainly no harm in having a detector that might be in addition to the 'code minimun.'
Even if at the same level, one can argue that a detector placed, say, over the living room would not be able to qualify as the one required 'in the hall outside sleeping areas.'

Secondly, the 'third wire' interconnecting smoke detectors is a fairly recent addition to the codes. Originally, detectors could be battery powered only, or line voltage only- not the 'battery back-up' now required. This house may very well have these earlier detectors.
There are also a detector or two out there that 'communicate' in ways that do not require that third wire.

I don't believe smoke detectors are required to be on dedicated circuits; if you want a light up there why not just add one? It can't be any harder to replace a detector than to hang a lamp.

NFPA 72 and all the building codes require smoke alarms to be placed inside each sleeping room, outside all sleeping areas, and on each additional level, including basements but excluding uninhabital attics.

Buildings wired under earlier codes are not required to be upgraded to the latest edition of the code unless a change of occupancy occurs (such as from an office to a restaurant)

NFPA 72 suggests that smoke alarms not be wired on a dedicated circuit. The thought is that the happy homeowner might want to smoke in bed, but is kept awake by the smoke detector going off, so he turns the power off and removes the batteries. As long as the lights and TV still work, he will never be bothered to turn them on again.

earlydean:

Which non-dedicated circuit should the smokes be connected to? Suppose the wiring is diversified where each bedroom has receptacles served by 2 different circuits (which may also serve other bedrooms) and yet another circuit for luminare(s). If it is on the light circuit, the smoker just brings in a table lamp or 2. If it is on a receptacle circuit, he just plugs the TV in another one using a cheap extension cord.