Due to a conflict with a newly-appointed fire inspector citing previously unnoticed violations of safety margins of a chimney construction in a house in Germany/Brandenburg, I had the pleasure to conduct a cursory research of the current fire safety codes (link in German).
The problem cited is that apparently one joists(?) from the roof construction lies slightly (1cm?) within the safety margin of 5cm of the chimney. It wasn't ever an issue on any inspection in the past, and there have been multiple inspections. Obviously, it is not an option to move either the chimney or the roof, and thus, resolving this issue is not trivial.
There is an option of contradicting the finding, but we need a good argument if we try this. My research of applicable codes indicates that 5 cm is always neccesary for walls, panels et cetera, which cover a significant portion of the surface, so the finding is not totally bogus.
However, there is a clause that exempts joists and other beams, for which only a distance of 2 centimeters from the chimney is required.
zu Holzbalken und Bauteilen entsprechender Abmessungen ein Mindestabstand von 2 cm ausreichend und zu Bauteilen mit geringer Fläche wie Fußleisten und Dachlatten, soweit die Ableitung der Wärme aus diesen Bauteilen nicht durch Wärmedämmung behindert wird, kein Mindestabstand erforderlich.
Translated loosely, this means...
A margin of 2cm is sufficient for joists and elements of similar dimensions No margin is required to elements of limited size such as Baseboards and Battens (google translated: Fußleisten und Dachlatten) as long as heat dispersion is not inhibited by insulation.
Upon request, the inspector replied that the beam was too large to be considered exempt, but would not offer a source. I understand there must be some place where the maximum dimension of such beams is defined, but it does not appear anywhere in the building code (at least not the relevant part I've linked above).
Thus my question is, where do I find the (size-) limits of beams. Is it some general building code, or ist there something like a DIN-standard? By chance, I do have access to the catalogue, but would need more pointers on where to look.
Also, any tips on how to deal with the issue in a constructive manner (fire-proofing?) would also be greatly appreciated, as the instructions given by the inspector were very unspecific ("Has to be dealt with by a specialized contractor" - which we are definitly willing to do, unless it means moving the attic.)
Thanks in advance!
Also, caveat, I used google translate several times, please let me know if you notice any mistranslations.