How to Add an Extension Onto a Gable Roof

Determing Your Roof Type

• Before beginning work on your extension, you need information about your existing roof. Determining your type of gable, for instance, helps you choose the right extension for your roof. Technically speaking, a gable is not part of the roof, but the triangular facade of a building that sits between two opposite, angled roof surfaces that meet at a point. Gabled roofs vary in complexity from those with a single simple gable to those with myriad gabled sections and extensions. Types of gables include standard gable, false front gable, L-shaped gable and gambrel.

Choose an Extension

• Dormers constitute a common extension for any type of pitched or sloped roof, including gabled roofs. These extensions work particularly well with gabled roofs because many dormers contain gables themselves, thereby reiterating the design of a gabled roof. Basically, a dormer consists of three three walls and a roof that rises from the level of a roof to add interior space to a building. Types of dormers include arch top, eyebrow, gabled, flared gable and pedimented. Look through building design reference books for dormer ideas for your roof. A type of dormer suited for a standard gabled roof, for instance, may not work well with a gabmrel roof, and vice versa

Design an Extension

• Once you decide upon an extension for your gabled roof, you must design it. Before starting your design, check your local building code for provisions regarding roof extensions. Design the extension with these regulations in mind. Finding visual aids, such as photos of your intended extension type, in architecture, design and building books and magazines can also help you with this step in the process. Create detailed drawings of your roof extension, including all parts you need, from screws and nails to lumber, shingles, sheathing and weatherproofing, as well as the dimensions of the unit. Gather all your materials and tools in one place to expedite the construction process.

Building Basics

• The process of building a roof extension essentially entails removing a section of your roof, building an extension, installing the extension and replacing roofing around the extension as necessary. This may require installing new rafters, re-shingling portions of the roof and other carpentry or roofing projects. The exact process you follow when building an extension on a gabled roof depends upon the type of extension you build.

Things to Consider

• Adding an extension to your roof requires cutting open the roof, usually for at least one work day. Never work on a wet roof, and never work on a roof when a chance of showers exists. Wearing a harness while working on your roof helps protect you from slipping or falling from the roof. Consult a building reference on roof construction or a contractor before cutting into your roof to make sure you know the carpentry and building skill required of this task – it involves not only building the extension, but reconstruction of portions of your roof. You can always design your own extension and hire a professional to help you install it, a preferable alternative to your roof collapsing.