To draw blueprints of porch plans, first obtain a sketch pad or graph paper pad. Take measurements of the area where the porch is to be built or updated. Use the sketch pad or graph paper to draw potential plans for the porch. Represent 1 square foot per one graph square, or designate a number of centimeters or inches to equal a square foot on a sketch pad, to keep the scale of the plan accurate.
Consider designing the porch to fit the style of the house so it looks as though it is an original part of the house. Choose an appropriate roof line and pitch for the porch roof if the roof is to extend out over the porch. Detail the angle of the roof in the plans. If the house has a second story, plan for that when fitting the roof line of the porch. Draw up multiple plans showing the porch from each angle to ensure it works with the existing structure.
Include columns, railings, stairs and porch screens or doors, if applicable. For a less formal porch, add railings all the way around the structure. Formal porches have columns without railings spaced out between 5 and 6 feet. Add as many details as possible to the plans to ensure the design fits the space in the best way possible. Add steps directly in front of the doorway and, if the porch is large enough, on either side for access to the side yard.