I live in an old 1860's house in Bucks County, PA. My back porch rotted out, and I was going to replace it. It was a T&G 1x4 material which was originally used, and I bought the same material (I think its Red Balau- or Phillipine Mahogany) to redo it. I am a little concerned because the porch is exterior, and is partially covered. Some parts of the porch will take some rain and sun. I am priming all the boards (front and bottom, as well as inside the grove and tongue) to try to lessen any moisture from getting into the boards. I was also going to pitch the boards away from the house somewhat so the rain sheds off of them. I planned on cleat nailing them with 2" SS L-shaped cleats. I wanted to install the boards as tight as possible (T&G) so that the floor is smooth and gaps are minimized.
The porch is roughly 8' by 18". It has a roof over 85% of it.
My question is will the boards cup and buckle if I install them tightly? Will they expand and pop once the weather gets rainy and humid?
I really appreciate any and all opinions/wisdom, thanks.