How to Frame a Sloped Porch

Check the slope of the porch floor with a level. Sketch an outline of the porch and note the direction and angle of slopes. Repair any serious slope, such as a steep drop to one corner because a support has slipped or weakened. Inspect the framing of a wood floor to make sure there is no rot or insect damage causing the slope. Look for depressions around a concrete porch that indicate water damage.

Frame an open porch with a slope using a post and beam approach. Set posts at the corners, and in between if the space is more than 8 feet, with metal brackets fastened to the porch floor to hold the posts. Adjust the height of the posts so the tops are level. Put beams on top of the posts and level them with a level, then add roof framing, preferably with prefabricated trusses. Fasten post holders with concrete or framing nails and a hammer.

Build walls for a fully framed porch, such as one with screens, on a flat surface, with top and bottom plates the width of the porch and vertical studs, spaced to the dimensions of the screens. Erect the side walls first and level them if necessary by driving tapered wooden shims under the bottom plate with a hammer to raise a low end. Put shims all along the wall as necessary to brace it against the porch floor.

Adapt framing for a partly enclosed porch on a slope, such as one with a roof and railings, by adjusting the height of support posts to make the roof line level. Install railings with the tops level; allow for any slope at the bottom of the rail spindles. Fasten spindles to a bottom plate set on the floor and adjust the height to compensate for the slope if a raised bottom plate would accentuate the slope.

Cover post brackets with wooden frames, boards mitered at the corners to make a box. Consider Craftsman-style framing for an open porch, with wide brick or wood columns at the bottom of support posts, topped with angled wood framing to the porch roof, as a good way to conceal a slope.