I think we architects often get confused when it comes to roof issues – IE: how to safely access a roof, and how building code applies to maintenance access to roofs. (This does not apply to promenades or roof decks that are accessible to the public.)
Building code does not really cover rooftop issues. They leave it up to OSHA.
OSHA considers it a working area. This means that the building owner needs to work with their maintenance staff to develop a safe work plan for any work on the roof. Conversely, they can leave it up to individual contractors to provide safe access to the roof during maintenance activities. Obviously, that could create liability issues for the building owner.
1) A tall building might require regular window washing. Thusly workers need to often go to the roof, and over the edge to wash the windows. The building owner would then want to provide safe access to the roof (via a stair or alternating tread device, check the building code for that…), provide fall protection on the roof, and provide a davit system for window washing equipment. In this case, the architect should be involved to provide the fall protection.
2) A new church has a very steep roof and steeple. Usually, no one goes to the roof. After many years, the roof wears out and needs to be replaced. The building owner has provided no access to the roof (none is required per building code) and no fall protection on the roof. Then, the roofing contractor needs to provide safe working for the roofing workers. In this case, the architect would not provide anything.
Here’s an OSHA booklet on stairs and ladders:
Here’s the massive OSHA guide on fall protection:
here is the OSHA guide on fall protection:
Things you need to watch out for:
– fall protection when a worker may need to go closer than 6′ to a roof edge
– varying roof heights a worker may need to cross – greater than 19″ high
– window washing
– safely accessing roofs with ladders (either fixed or not)