How many squares wound I need for 5-6 ft porch

Hello there, Thank you for your inquiry. We would recommend to consult with the Prodesk at your local Lowe's store and they can help to determine how many boards you may need for your project. There is also a calculator tool on Decks.com that you can use. It will ask for the dimensions of your deck and provide you with an estimated board count. We also have a "Deck Designer" tool that you can utilize to obtain a materials list. I hope this information is helpful to you. Please let us know if you have any other questions. Thank you, Jessica- Trex Customer Care Team