Don Vandervort, Head Homeboy, has written more than 30 DIY home improvement books, been a segment host on HGTV, served as MSN.com's home improvement expert and written countless magazine articles.
An introductory look at patio roof and gazebo foundations
Patio roofs and gazebos are typically supported by a foundation--either a concrete slab (in some cases, an existing patio) or a series of footings and piers. The foundation distributes the structure's weight and anchors it against settling, erosion, and wind lift. The foundation also isolates the posts or walls from contact with the ground, mitigating the chance of decay from moisture and insects.
Typically, a foundation's footing must extend into solid ground. In cold-climate areas, it must extend below the frost line so that it is not disturbed by frost heave.
Foundation requirements are set by local codes; a steel-reinforced concrete footing that extends 6 inches below the frost line, as shown in our article on how to pour a concrete slab, is typical for patio roofs and gazebos with built-up floors.
The footing supports a poured-in-place or precast concrete pier, which in turn supports a post. The placement of footings and piers is dependent upon the post locations, which in turn are determined by the beam and rafter spans.
Patio Roofs & Gazebos All you need to know about building outdoor structures, from an inspirational gallery for unique ways to extend your living space outdoors, to step-by-step photo sequences to build an outdoor structure precisely suited to your needs.