I am going to be building a new dining table and bench for our house. It is a simple design - 8' long with slightly tapered legs and a bench to match. I am a little worried about sag in the bench. I punch the numbers in to the sagulator, and if 4 adults were sitting on the bench it said there would be excessive force.
That doesn't seem right to me. I have sat on benches 7' but maybe there were supporting elements I didn't notice. The entire structure is white ash with 1" tenons into the legs. There are cross support as well (see image below). Should I be worried? Is there some other support I should add for the table or bench?
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