Two common methods of framing gable roof overhangs are ladder framing and outrigger framing. New construction and roof retrofits are opportunities to upgrade the gable roof overhang to meet standards and building codes and to decide if selecting an above-code strategy for an added level of protection is the right choice for the project. Ladder framing is constructed using two long parallel boards that are connected by short blocks, like the rungs of a ladder.
This framing is attached by nailing through the gable wall sheathing into the last truss or rafter. Roof sheathing is installed above the overhang and provides structural support and resistance to wind uplift.
Ladder framing is typically limited to shorter overhangs of 8 to 12 inches. Outrigger framing is typically used for overhangs greater than 12 inches. The size of the gable truss or rafter or truss is adjusted such that the top level of the end truss or rafter is less than the top level of the rest of the trusses or rafters to provide enough space for the outriggers to pass above the end rafter or truss.
Outriggers, which may be 2x4 members or 2x6 members, are then installed on top of the gable truss or rafter so that they butt up against the truss or rafter next to the gable truss and extend outwards to support a fascia board along the edge of the overhang.
See Figures 2 and 3. The International Residential Code IRC requires exterior building components and their attachments to be capable of resisting design wind-pressures. Homes located in coastal high-wind areas including Hurricane-Prone Regions generally require enhanced attachment that can withstand greater wind speeds than the rest of the country.
Confirm with the local building department if the house is in a hurricane-prone region and if local requirements exceed those of the IRC. The IRC specifies minimum requirements for continuous roof sheathing at gable end walls, including fastener nail type, spacing, and penetration depth into structural members.
See the Compliance tab for details. When overhangs exceed 12 inches, most IBHS standards require additional members or outlookers to support the overhang sheathing. Outlookers are framing members that extend to the top of the gable end wall to support the roof deck overhang and are oriented with their larger dimension perpendicular to the roof sheathing. It also requires the gable end soffits to be unvented since gable end soffits are susceptible to wind-driven water intrusion because of the large amount of water that accumulates on the gable wall when it faces into the wind.
The Federal Emergency Management Agency FEMA recommends a maximum of 8 inches of gable roof overhang and a maximum of 4 inches on center fastener spacing for ladder framing in high wind regions. It also requires the spacing of the overhangs to be not more than 24 inches on center and the overhangs at gable end wall framing or truss framing should not be notched. Determine if local building codes have specific additional requirements for framing gable roof overhangs. The International Residential Code requires the roofing members to be designed in accordance with the minimum live loads table see below or the snow load table provided in the IRC IRC , Table R Table 1.
Compliance The Compliance tab contains both program and code information. Code language is excerpted and summarized below. For exact code language, refer to the applicable code, which may require purchase from the publisher. While we continually update our database, links may have changed since posting.
Please contact our webmaster if you find broken links. Table R Less than 2 feet separation distance is not permitted, and they are not required to be fire-resistance rated if the separation distance is greater than 5 feet. The fire-resistance rating is permitted to be reduced to 0 hours on the underside of rake overhang where gable vent openings are not installed.
For dwelling with fire sprinklers, the fire-resistance rating is only required if the fire separation distance is 2 feet and not required if it is 3 feet. Continuous sheathing methods require structural panel sheathing to be used on all sheathable surfaces on one side of a braced wall line including areas above and below openings and gable end walls and shall meet the requirement of R Wood structural panel used as roof sheathing shall not cantilever more than 9 inches beyond the gable end wall unless supported by gable overhang framing.
Roof assemblies shall have uplift resistance and be designed in accordance with accepted engineering practice. Retrofit: , , , , and IRC. Section R Additions, alterations, renovations, or repairs shall conform to the provisions of this code, without requiring the unaltered portions of the existing building to comply with the requirements of this code, unless otherwise stated. See code for additional requirements and exceptions.
Appendix J regulates the repair, renovation, alteration, and reconstruction of existing buildings and is intended to encourage their continued safe use. Fortified Home Hurricane Standards. Section 3. Gable end overhangs must be constructed and attached to gable framing to resist appropriate wind uplift loads. Gable rake soffit vents become a problem when porous soffit panels or screen vents are installed on the bottom surface of the roof overhang at the gable end and there is nothing to block the wind-driven rain coming through the vents from entering the attic.
Gable end overhangs shall be designed and constructed to resist uplift wind loads. Most current high-wind wood frame construction guides do not require additional framing members to support the overhang until the length of the overhang exceeds 12 inches.
When overhangs exceed 12 inches, most standards and guides require outlookers to support the cantilevered overhang sheathing.
Outlookers are usually 2x framing members that extend out past the top of the gable end wall to support the roof deck overhang and are oriented with their larger dimension perpendicular to the roof sheathing, Wind uplift pressures on outlookers at the edge of gable end roofs are some of the highest pressures the structure experiences during high-wind events.
If there is no retrofit-specific information for a section, that heading is not included. Select framing members that are at least 2x4s for gable end overhang retrofits. The members should be spaced no greater than 24 inches on center. The outlookers and gable end wall framing or truss framing should not be notched. Also add a joist hanger to secure the overhang member to the roof framing member.
Complete the retrofit before the roof sheathing is strengthened. More Info. Access to some references may require purchase from the publisher. The Building America Field Kit allows you to save items to your profile for review or use on-site. Sign Up or Log In. Framing of Gable Roof Overhangs Print. Scope Images. If the house is in a hurricane-prone region or other high-wind area, determine the framing approach based on the length of the gable roof overhang. Ladder framing and outrigger framing are the two most common methods.
Outrigger framing, using outlookers, is recommended for overhangs greater than 12 inches deep. Install gable roof overhang framing with correct lumber dimensions using adequate connections. Attach fascia board at the edge of the overhang. Install roof deck sheathing extended over the gable framing and installed with correct fasteners and fastener pattern.
This guide will help you decide what shed overhang is best for your shed and walk you through the installation process. Quick Navigation.
An overhang is the portion of the roof that runs past the wall, providing coverage for the space around the foundation of your shed. Overhangs can vary in width from a few inches to several feet. On sheds and homes, overhangs are commonly referred to as eaves or rakes, depending on where they are located. While shed overhangs may seem forgettable, they have many important benefits that protect your shed and improve its aesthetics.
Shed overhangs also help to regulate the temperature inside the shed by blocking sunlight from shining directly through windows in the summertime when the sun is higher in the sky. During the winter, when the sun is lower in the sky, overhangs allow the sun to shine through the windows to warm the shed. Sheds with large overhangs can also provide additional storage space for equipment.
The space under a shed overhang is a dry place to stack firewood or lean your wheelbarrow. There are also aesthetic benefits to roof overhangs. Like it or not, a shed will be a significant feature in your yard. You want that feature to add to the appearance of your property, not detract from it. Overhangs add character and help your shed avoid that boxy flat look.
There are two types of roof overhangs two consider. You may want one or the other or both. A rake is an overhang located on the gable end of your roof. A rake overhang is created by extending the roof beyond the gables of your shed. An eave overhang is located on the longer sides of the shed. An eave is created by extending the slope of your roof beyond the walls of your shed.
Most sheds with overhangs incorporate both rakes and eaves into their design to give the shed a balanced look. And while it may cost you a little more in material, the benefits, as I discussed above, are more than worth it. How big to make the overhang depends on what you need it for. This will protect the tops of windows and door openings from moisture while directing water away from the foundation.
With a flat shed roof, the roof simply extends past the wall plate to provide an overhang. Because this style of a shed has a flat roof, it can facilitate a wider overhang, which is ideal for storage. For gabled roofs, the roof rafters extending beyond the wall caps, creating an angled roof overhang on the eaves. Due to the steeper angle of gable roof, the maximum width of the eaves is narrower than other shed styles.
A rake on the gable end of the roof can be created with the construction of additional roof framing. For slanted roof sheds , overhangs add character and facilitate proper drainage. For gambrel roofs, the design is a little different. Extensions are made to the gabled ends to provide coverage over the entrance.
Rather than extending the roofline to create eaves as you would on a flat or gable roof, eaves on gambrel style roofs are flared due to the steep angle of the roof.
Since Lean-to sheds are attached to larger structures, they can sometimes receive runoff from the structure they are paired with.
Overhangs also add character by eliminating the boxy utilitarian look this style of the shed can sometimes have. Next, cut two additional sets of rafters for each gable end. Cut the outriggers out of 2x6s, making sure to account for the width of the rafters. Then create your ladder by attaching the rafters for the rake to the ridge board.
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