Install Tongue & Groove Porch Decking
If you want to create a covered cumaru porch, then the tongue & groove profile is the best choice. It does require a different method of installation, though.
Make sure to build a pitch into the porch so that water can drain off. Also, tongue & groove porch decking is designed for covered areas only.
1. Tongue & Groove decking must be installed directly onto the joists, not a sub-floor, so that it can get adequate ventilation.
2. At a 45° angle, predrill into the seam where the boards will meet.
3. Drive a stainless steel trim head screw through your pilot hole and into the joist.
4. Slide the next deck board into place. It should cover up the trim screw head.
If installed correctly, your porch should have a seamless surface. Enjoy your new cumaru porch!