• If you want to build a porch that has the look and feel of natural wood, but is more resistant to the damaging effects of moisture, insects and microorganisms, pressure-treated lumber can help. Manufacturers produce this lumber by using pressurized chambers to infuse wood, like yellow pine and Douglas fir, with preservative chemicals. In comparison to a standard wood porch, a pressure-treated porch will typically require less maintenance.
  
  

Floor Patterns

• Most pressure-treated porches have standard, linear floor patterns, wherein all of the planks of lumber flow in the same direction. To give your porch a more stylized and exciting appearance, try straying from the norm and using different, more complex flooring patterns. One option is to create a basket weave pattern, which features alternating sections of vertical and horizontal pressure-treated planks. Another option is to create a herringbone pattern, which features columns of diagonally-oriented planks. In one column all of the planks are parallel and sloping in one direction, while in an adjacent column the planks are parallel, sloping in the opposite direction.
  
  

Railings

• Pressure-treated porches typically have post-and-beam railing designs, which consist of thick lumber uprights with horizontal lumber beams running across them. To enhance the aesthetic value of a post-and-beam railing design, try replacing basic four-sided posts with decorative posts, which are also known as balusters. Using turned balusters on porch railings can help contribute to a Mediterranean feel. Turned, or machine-carved, balusters have fluting and other three-dimensional shapes adorning them. Another idea, which can help you create an Asian-inspired porch, is to use balusters that have a Chippendale effect. These balusters branch off, like spider webs, into a variety of directions instead of running straight up and down.
  
  

Lumber Choice

• The American Wood Protection Agency classifies pressured-treated lumber according to retention levels, or the amounts of preservative that remains within the fibers of wood following pressurization. Pressure-treated lumbers with high retention levels have high use category (UC) numbers. For example, UC2 pressure-treated lumber, which the AWPA recommends for indoor use, has a retention level of 0.25 pounds or preservative per cubic foot of lumber. In contrast, UC4C lumber has a retention level of 0.80 pounds per cubic foot of lumber and is suitable for use in moist environments. The type of pressure-treated lumber you should use for your porch will depend on a number of factors, including whether the lumber will come in direct contact with the ground, whether your porch is covered by an awning or other structure and the amount of precipitation your area receives.