I'm looking about spanning 15' for a gazebo. trying to figure out what dimension beams I need. The Gazebo will be 15'x10'. How big will the beams have to be. at 1/2 the distance on 15' I will have a perpendicular beam running to carry 2x4's running parallel to 15' beam edge. I live in California in there with be no roofing material.. I will be using redwood for lumber Thanks
Build the framework for all four walls. To account for the fact that the front and back walls are different from each other (due to the doorframe in the front) and the side walls must both be sloped (to prevent rain from collecting on the roof), each of these will have to be tackled somewhat differently. It’s easiest to construct the back first, the front second, and the two sides last, as shown in the numbered image below. See How to Frame a Wall for more information before you read the instructions below.[5]

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