porch roof

How to Add a Porch Roof to an Existing Roof

Thinking of linking a porch roof to your home’s roof? This is a job best left to skilled professionals. If you’re dead set on trying it yourself, however, it’s important to know the proper procedure. We’ve provided a step-by-step process, along with a word of caution about potential mishaps that might occur along the way.

A Word of Warning

When built well, a porch roof can help protect a porch from weather-related damage while providing a bit of shade for recreation. If you have an adequate amount of carpentry experience, you may be able to complete this job yourself. With that said, the task does come with risk, not just to yourself but to your house.

Inexperienced do-it-yourselfers can suffer serious injuries working with step ladders and electric saws. They also often inadvertently cause damage to their properties. What’s more, even if you are able to successfully construct a porch roof, blending it into your home’s existing roof requires careful planning and a bit of know-how.

With this in mind, consider hiring a professional contractor to construct and connect your porch roof, so you can be sure the project is done correctly and safely.

Step 1

Before you start any construction, check with your homeowners association and inquire about local building codes. Acquire any and all necessary building permits to avoid costly fines. Some local building code offices require homeowners to submit plans for approval, so you may have to draw up some thorough plans before you start the job.

Step 2

Construct columns to support the considerable weight of your new porch roof. If your porch is square, you will need columns at the corners farthest away from the house. Using 2×4-inch studs, construct a frame for the columns that run vertically from the porch’s floor to the soon-to-exist porch roof. Brace both column frames in place using concrete screws and L-brackets. Conceal the column frame by covering it with brick, siding or another outdoor material that will match your home’s exterior.

Step 3

Affix a sturdy sill plate to your home between the porch’s two side supports. A sill plate is essentially a piece of wood that will secure the supports to your home’s roof. It should sit flush to the upper edges of the support columns.

wooden porch roof

Step 4

Position your rafters over the top of your sill plate. You can use joist hangers to help mount each rafter to the home. Use galvanized screws to fasten the rafter to your sill plate. You will need to position your rafters based on the planned pitch of the porch roof. The porch roof could have a shallow roof pitch or may match the pitch of your house. If you choose a shallow pitch porch roof, you should use 2×6-foot rafters.

Step 5

Frame out the roof of your porch roof by adding rafters until it extends about a foot past your support columns or porch walls. Mount a fascia board on the sides and front of your porch roof frame to compensate for inconsistencies in rafter length. Then cover your rafters with plywood and hammer the thin sheets into the rafters until they are secure.

Step 6

Choose roofing materials that will match your home’s existing roof. In most cases, you can use the same materials for both structures; however, you must make sure the materials are designed to hold up for the pitch of your porch roof. Different types of roofing materials function much better when installed at a specified roof pitch, so you must check with the product manufacturer to ensure that the pitch of your porch roof matches their recommendations.

Step 7

Apply your chosen roofing materials to the porch’s roof starting near your home and working toward the edge of the porch. You may need to pull some of the house shingles off to create a consistent, seamless pattern extending from the home to the porch roof.

As you can see, linking a porch roof to your home’s roof isn’t as simple as you may think. If you’re not careful, the roof could collapse. You could also end up damaging your home’s roof, resulting in leaks that can lead to thousands of dollars in damage from rot and mold infestations. Instead of trying this task alone, it’s almost always safer to get help from a reputable contractor.

If you need a new roof for your home or an addition, A to Z is here to help. We’ve developed a well-earned, widespread reputation as one of Colorado’s leading roofing contractors by providing reliable, expert workmanship and honest, attentive customer service. Contact our team to learn more and get a free estimate on your next roofing project.

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