House was built in 1920. A few months ago, an old metal roof was removed and shingle roof installed. Apparently, they put the roof decking over the battens from the old roof. The rafters are 43"OC… quite a span? I’ve never seen this before. There is no indication of spread or other damage but this has been in place for only a few weeks. Replacing the metal - or tin - roof with sheets of plywood and shingles - I’d like to see an architect or engineer’s recommendations on these modifications
given You have no snow load to worry about and it is such a small roof, I’m not sure i see any real problems, of course I’m in my office in Ohio and You were there…If it concerns You, mention Your concerns…
Part of the wind mitigation report for hurricane insurance… minimum standard is 24" on center.
Discounts go up based on type and spacing of nails.
Insurance may flat out deny that house
dhorton2 has it right, especially on a home that age in today’s FL insurance market. Good luck finding insurance on that house with those modifications unless you have a sign-off from an engineer. The weight load must be huge. I’d bet it was at least a little spongy, wait until it sits in the humidity for a while, the neighbors might get seasick looking up.
Look for the APA span rating (black ink stamp) on the backside of the sheathing. I cannot read any in the pics your provided. A span rating of 48" is needed to cover the 43" IMO, which equates to 23/32" or 3/4" thick plywood, perhaps 5/8" absolute minimum. If they used 1/2" or thinner plywood, likely problems down the road.
That is formost in my thoughts… but in the last year they have “messed” with it. In the north, you worry about snow load… in Florida, we worry about wind uplift. With the removal of the metal roof, applying roof decking, and then shingles, Have these modifications changed the dynamics, and if so, were these changes designed/approved by an engineer or architect… or not. Will this roof fly away the next time we get 50mph winds?
