Main lug only load center or sub panel location

[champion]

I was told by a home owner that an electrician told him it was ok to install a sub panel in his attic as long as it was overcurrent protected by the main service panel located in the 1st floor of the home.
The home is a residential 1200 sf home, no basement and only 1 habitable floor. The panel that I saw in the attic is a 100amp main lug only panel accessible by a portable ladder fed with a 50amp 2 pole breeaker. The service is 100amp at the dwelling. The intent is to power additional circuits for the kitchen area and sub feed a panel in the detached garage from the attic located panel.
The temperature of the attic will get hot, very hot in the summer and I am wondering if I can get some input regarding any non compliance code issues regarding this installation. The head room in the attic is only 5 feet at most from the highest point in the attic. (ceiling joist to roof joist)
I am concerned about conductor deration, overcurrent device accessibility, premature tripping due to heat and working space requirements.
The only access to this attic is via a portable ladder. (not permanent).
Any time a breaker trips in this panel, it will be time to get the ladder out.
Can I get a bit of direction in identifying non compliance here for my own benefit?
So far article 110 is the direction I have started.

Thank You

 

[augie47]

few areas to check:
240.24 ref: readily accessible
110.26(E) headroom

those two alone should be enough to warrant a "NO"

 

[electricman2]

IMO, the exception to 110.26(E)would allow it, but the definition of "readily accessible" specifically says you must not have to resort to "portable ladders", so 240.24 would prohibit it unless you install a folding ladder.

 

[wbalsam1]

I agree with the other posters here so far, and would add that a panel fed from a panel fed from a panel in a 1200 sq ft house warrants a real hard look. :-?