9 3 built up roofing because this is a wood detailing manual this section will only attempt to highlight some basic edge conditions that often adversely affect adjacent wood construction.
Roof overhang framing details.
The following conceptual details figures 9 1 to 9 6 show some of the typical conditions commonly encountered.
Overhangs can vary in width from a few inches to several feet.
What is a roof overhang.
Start with roof framing.
At the rakes however with a nod to yankee frugality and clean modern lines we kept the roof trim as close to flush as practical while still allowing for a rain screen channel ventilated at the top as well as the bottom.
An overhang is the portion of the roof that runs past the wall providing coverage for the space around the foundation of your shed.
Position the square at the end of the rafter board with the tongue on your left and facing away from you.
When designing a gable end eave without a return the dimensions to look at are the width of the trim set between 6 in.
That is their functional purpose.
The first approach to achieving a strong durable struc.
They also help to frame windows on upper stories.
Eave overhang detail with that in mind we kept a roof overhang at the eaves as it provides a nice shadow line and protects the second floor windows from a bit of the summer sun.
For wood framed construction comparable details are contained in the american wood council wood frame construction manual.
Avoid gable ends that are over 8 in.
Wide especially when the eave overhang is less than 12 in.
Thick and the overhang from the side wall set between 12 in.
However there is also an architectural purpose to them.
Eaves form the overhang to distribute water clear of the walls.
In this system the outer framing under the overhanging roof deck sheathing is formed by two parallel long 2x4 s or 2x6 s that are connected together laterally by short blocks like the rungs of a ladder.
As shown earlier in figure 2 there are some prescriptive details in the irc for cold formed steel construction.
For the cantilevered outlooker method connection design loads are published for various wind speeds.
American forest paper association wood construction data 1.
Ladder details are usually adequate if the overhang is less than about 8 inches although they are frequently used for longer overhangs.
These are limited to an overhang length of 12 and apply for up to 139 miles per hour ultimate wind speed.
Add the length of the overhang beyond this mark and.
After the end points of the plates are located the length is found using a base 1 triangle for a 6 in 12 pitch where the hypotenuse is 1 118 times the length of the base.
On sheds and homes overhangs are commonly referred to as eaves or rakes depending on where they are located.
The ladder detail is frequently used when the builder continues the same truss size or rafter size all the way through the gable end.
The diagonal plates are 3 1 2 inches down from the tops of the rafters to support 2x4 lookouts for framing the rake.
Measure form the top of this line down the board to determine the line length or length of the rafter less the ridge.
