1-hr Fire-Rated Exterior Staircase

[Jordan Kaiser]

Hi Everyone,

I am renovating a property (my first one!) which is within 10 feet of the neighboring building. I have to replace an egress staircase from the second floor which was originally made from pressure treated wood. The local building department wants the replacement stairs to have a 1-hr fire rating due to the proximity to the neighboring property. I haven't yet found a pressure treated and fire rated lumber or an intumescent paint that can be used for exterior applications. Full metal stairs are always an option but that would completely blow the budget which already has a razor thin margin. 

Anyone have any economical advice to satisfy these requirements?

The property is zoned commercial but has been used as a residence since 1850 including as a duplex for many years (though I don't know exactly how many).  

Thanks for any and all advice!

Regards,

Jordan