To 18 in depending on the style of the building.
Gable roof no eaves.
A gable roofis a type of roof design wheretwo sides slope downwardtoward the walls and the other two sides include walls that extend from the bottom of the eaves to the peak of the ridge.
When an eave overhangs the gable end it is known as a rake.
The most common way to add ventilation to an attic is by installing air intakes in the soffits and putting an outlet at the gable of the house.
The final step is putting the roof on the eave and addressing what happens in the gable itself.
In fact providing exit venting at a roof ridge or at gable end vents on a building with no intake venting at the building eaves will increase the building heating costs and can also add to attic or under roof condensation moisture and mold problems.
In contrast a gable or rake is the overhang of a building that occurs on the side that is topped by a gable roof.
This is the portion of the roof that protrudes beyond the side of a house or building.
When designing a gable end eave without a return the dimensions to look at are the width of the trim set between 6 in.
An eave is defined as the edge of the roof that overhangs the face of a wall.
Avoid gable ends that are over 8 in.
The top edge of the board rests against the roof decking and the bottom edge covers the siding or brick.
Wide especially when the eave overhang is less than 12 in.
It is made by extending the ridge board beyond the gable end doubling the last rafter to provide a nailing surface and installing one additional rafter a distance equal to the desired overhang.
Do not set it to match the main roof slope of the house.
This video will.
Like rain snow sleet wind and hail.
The eave roof and gable.
A passive ventilation system should have air inlets at the base of the roof usually in the soffits and outlets in the peak or gables.
Refer to my architectural roof types blog.
A slight return just enough to keep water from pooling is all.
Thick and the overhang from the side wall set between 12 in.
Now that we have that out of the way let s get to the heart of the matter venting a house with little to no eaves or soffits.
The purpose of your home s roof is to protect the entire structure and you from weather.
Remember the roof on the return is there just to shed a small amount of water.