Nothing extends the usage of your deck or patio like having a roof overhead. A permanent structure can handle the ravages of winter without having to retract seasonal devices for the next storm. Once in place you will discover the joy of being outside during a gentle rain in any season if it isn’t too windy, and have shelter from summer sun or thundershowers.  What should you consider?

For design options first answer these questions:

• Is the area you want to cover adjacent to the house?
• Is your house single story?
• If so, does the roof slope rise up from the adjacent house wall, and how steeply, or is there a gable end wall?
• Do you have a two story wall next to your patio?

What these questions are designed to determine is whether or not you can attach your new patio roof to your house or whether it needs to be free standing, and what the best design is. If you have a…

Gable end. You may be able to extend a gable end roof out over your patio area. If a small gable you are limited to its size and location.  If a large gable you can extend the part of the gable that suits your needs.

Sloped roof. If your single story roof slopes away from your patio area you may be able to tie into your house roof at a point up the roof a bit with a lower pitched “shed roof.”  Here is an example of a real life analysis:

• You discover the distance from patio to roof above your house wall is 10′ 6″ and the roof pitch is 6 in 12 (6″ rise per 12″ run, or horizontal distance). For outside patio roof support you plan a 4″ x 10″ beam on posts set 12′ out and 8′ high. If you extend your patio roof from house at just over wall, you have a 2 1/2 in 12 pitch–enough for torch down or metal roofing but not composition shingles. By tying in 8′ up the house roof, your patio slope becomes almost 4 in 12, enough for shingles.

Two story wall. You can attach a shed or sometimes a gable roof to your house wall. In this case second story windows shape your design. You want your finished roof surface to be at least 2 1/2 to 3″ below any windows. Roof flashing will tuck under siding and trim.

Low or flat roof. If your house roof is too low or flat to attach a patio roof to you will need a free standing structure. Whether shed or gable style if you overlap your house roof it needs to be enough above the house roof to allow maintenance. Since this creates an open area through which rain can blow, some create a dettachable or hinged section that comes within a few inches of the house roof but can be moved when needed.

Other concerns you might have:

Structure. Structural design needs to be sufficient to support roof load and have adequate shear strength. The first is accomplished by using code approved span charts in sizing lumber to the project. The second is creating resistance to shear or lateral movement. Methods include diagonal block sets in rafters, forming an “X”; large custom made metal “L” and “T” braces where posts meet beams;  and glued plywood sheathing over T & G pine which covers rafters. This last keeps roofing nails from showing through in an exposed rafter design.

A good carpenter/contractor should be able to accomplish a good design, but it can be beyond their skill set, so don’t hesitate to check up on proposals. For instance, an otherwise wonderful professional firm can do excellent aesthetic work but have little background in the structural needs of free standing post and beam supported roof projects, since these amount to a very small percentage of the overall building landscape.

Use recommended professional roof addition builders to create a strong, safe, beautiful, and long lasting patio roof–one that you will enjoy for decades.