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Machinc, General Contractor
Category: Home Improvement
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Experience:  Has written home improvement articles since 2008. Earned South Carolina Residential Builders License in 1991.
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This is a question for a home builder or design engineer concerning the Utah building code. In Utah does the code say that on the Gable end of a two-story structure must be sheathed first before the decorative roof-eve can be added or is it acceptable to put the roof-eve on the rake wall before the sheathing goes on.

The question came up because one of the framers thought for structural integrity that the sheathing had to be on fist covering the whole surface and tying the rake wall into the first floor.
Submitted: 2 years ago.
Category: Home Improvement
Expert:  MsBabyD replied 2 years ago.

MsBabyD :

Hello! I am here to help you with any questions you may have.

MsBabyD :

As an inspector International I will look up this code for you. 1 farmer can not stop construction unless he is connected

MsBabyD : Roof Basics


Virtually all roofs on new homes today are built with pre-fabricated trusses. These go up much faster than hand-framed roofs, and even on a small addition it's often easier to order a few trusses and set those than to frame the roof by hand.

So we'll assume that most people will lean toward trusses in their own projects and explain the following basic steps on how to build a simple gable roof with trusses.

For definitions throughout this project, see Framing Glossary.

But there's always a bit of hand-framing to be done on a new roof, even if the main structure is built with trusses--especially on additions where the new roof usually has to be tied in to the old roof or to an existing house wall. And you might be interested in a couple other roof projects.

So in our next roof framing page, Special Roof Techniques, we'll give you a quick idea on how to tie a new roof into an existing one, how to hand-frame a small hip roof and how to build a gable dormer.

CAUTION: Roof work is always dangerous, so please read over some Important Safety Information we've filed on site here before starting your next project.

Ordering Trusses

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]117.24137931034483[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Roof trusses are generally made to order for a given construction or remodeling job, and they usually require about 2 to 3 weeks of lead time.

On most projects, your lumberyard or home center can place the order for you, but you must supply the dimensions, pitches and styles (gable, hip, flat). Those are usually available on the plan (which you need to get your permits anyway).

Marking Cap Plates

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]102.94117647058823[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Once the walls are plumbed, squared and straightened they're ready for trusses. But before raising them into position it's best to measure and mark on each cap plate where the heel of each truss will land.

They're usually secured 24 inches on center, so you just start on one end marking the first truss flush with the outside edge of the cap plate and making marks for the subsequent trusses at 24-inch intervals (including a mark at the other end for the last truss). (Depending on the design, it may also be necessary to space the first two trusses 23-1/4" on center to ensure that the first piece of 4' x 8' roof sheathing is flush on the outside of the first truss but lands in the middle of a subsequent trusses.)

Mark the truss positions on the opposing cap plate starting from the same end where you started measuring off the first cap plate to line the trusses up properly.

Securing Gable End Truss

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]132.72727272727272[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]To frame a gable roof, the truss manufacturer will include 2 gable end trusses which are assembled with more vertical members than the other trusses to support the gable end sheathing.

Raise one of these into position first at one end of your truss run, usually at the point where you started your measurements, make sure it's flush with the outside edge of the cap plate it's resting on and toenail it in place.

Nail 2 or 3 2x4 braces from the truss down to the ground outside the structure. Use those to hold the truss plumb and screw the braces into stakes driven into the ground.

IMPORTANT: Be sure to add any lateral or vertical bracing required by codes in your area to resist high winds. Your local building officials will help familiarize you with the necessary steps during the permit process.

Lifting Trusses

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]98.38709677419357[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Once the gable end truss is fully secured, plumbed and braced, you can raise the other trusses up onto the walls. This can be awkward since trusses are usually long and unwieldy.

On large projects, contractors will often hire a crane to lift the trusses up. Doing it by hand is possible (and cheaper) but it requires adapting steps similar to those below to fit your situation.

  • Set one end of a truss on one wall plate with the truss upside down.

  • Set the other end on the other plate.

  • Swing the truss into its upright position.

  • Rest it against the gable end truss already secured.

  • Raise the other trusses the same way, one by one, and stack them against the gable end truss, making sure the other gable end truss is the last one to go up.

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]120.1923076923077[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Two people can handle this routine if they have ladders and scaffolding standing by to safely climb up into position to swing the trusses up and stack them up one by one. But ideally, there would be a couple people up on the wall plates pulling the trusses up and a couple people below pushing--especially on 2-story buildings. (And possibly a fifth person with a pole or a 2x4 to help tilt up the peaks)

Positioning and Bracing Trusses

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]131.4814814814815[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]After the trusses are all stacked up on the wall plates, you then walk them back into position one at a time starting with the second gable end truss (which goes on the far end from where the trusses are stacked) working your way back to the first gable end.

It's a good idea to brace the second gable end, plumb it and secure the same as described on the first gable end. But don't try to brace each of the following trusses like that. Instead, have a few 8-12 foot lengths of 1x4 on hand to serve as braces.

truss spacerMark those off with the same 24" on center sequence that you marked on the wall plates.

Then once you have a few of the trusses in place, nail the end of the brace over the second gable end truss up along the peak and then nail it to the other trusses, lining each one up with the marks you made. That'll not only set the proper spacing but it will also plumb up the other trusses (assuming the gable end truss is still plumb).

TIP: Sometimes that second gable end truss is NOT exactly 24" on center from the neighboring truss. In that case, just measure the exact distance between those two trusses along the cap plate and move the mark on the end of your brace as needed to match that distance.

Building Gable End Overhangs

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]104.2016806722689[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Sometimes gable end trusses are made 1-1/2" or 3-1/2" shorter than the other trusses you order. That's to help you extend the roof out a few inches over the gable end.

Once the other trusses are in place but before you start sheathing, mark the tops of the gable end trusses and the trusses next to them 24" on center.

Cut a series of 2x4 lookouts to a length equaling the distance between the 2 ends trusses plus the length of the overhang (usually 6 to 12 inches).

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]108.47457627118644[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Nail the lookouts in place with their ends nailed to the side of the first full trusses and the other ends running out over the gable end trusses with the tops of the lookouts flush with the tops of the full trusses.

Sheathing Roofs

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]125[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Before putting on the sheathing, you should plumb cut the rafter tails to their proper lengths and install a sub-fascia board (if that's to be part of your soffit framing) so you know where to start the sheathing.

Set a level against the wall and use that to measure along a level line to the bottom of the first rafter tail, moving the level up or down till the tail hits the length of your overhang minus 1-1/2" for a sub-fascia. Put a mark there, make the same measurement on the last rafter tail and snap a chalkline between the two marks, marking the bottom of all the rafter tails.

Use the level to mark a plumb line up the side of each rafter tail at the chalk mark and cut along those lines with a circular saw. Then cut and nail the sub-fascias in to the ends of the rafter tails, extending as needed at each end to account for the gable end overhangs.

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]131.4814814814815[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]The first course of sheathing then goes in along the bottom of the trusses. You can set the first piece on either end, lining it up with the outside framing, but if you've built an overhang that's not exactly 24" you'll have to cut the piece at the other end in the middle of a truss as required.

Nail in as many pieces as needed to reach the other side, letting the end of the last piece run wild. Start the next course of sheathing on a different truss to stagger the seams and strengthen the roof and continue sheathing the roof till finished.

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]124.77064220183485[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Snap chalklines over the wild ends to reflect the overhang and cut the ends off with a circular saw.

You can also let the last course of your sheathing run up past the top of the trusses and then cut that row to the proper height when all the pieces are in.

Once the sheathing is finished, you can roll out and staple down 15-pound builder's felt to protect the sheathing from moisture and heat.

Building Soffits

[IMAGE][SRC][/SRC][ALT][/ALT][WIDTH]130.43478260869566[/WIDTH][HEIGHT]100[/HEIGHT][STYLE][/STYLE][/IMAGE]Once you've plumb cut the rafter tails to a uniform length and installed a sub-fascia board (as described above), use a level to mark a point on the wall at each end of your rafter run level with the bottom of the sub-fascia board. Snap a chalkline between your marks and nail up a 2x4 or 1x4 nailer with its bottom flush with the chalkline.

Measure the distance between the inside of the sub-fascia and the nailer you just installed, cut one 2x4 lookout at that length for each rafter and nail those in between the nailers with their bottoms flush with the nailers, nailing one end into the sides of the rafter tails and toenailing the other end into the nailer on the wall.

Nail your soffit material up into the bottoms of the sub-fascia, nailers and lookouts, measuring and cutting the pieces to make sure any joints fall on the lookouts for proper strength.

Later you can nail fascia board material (usually 1x6's if you've used a 2x4 sub-fascia) over the sub-fascia to finish off the edge and crown molding along the wall to cover any gaps between the soffit material and the siding

MsBabyD :

Utah Building Codes

Building Codes References

Utah's building codes are mandatory statewide. Local jurisdictions may amend them but only with state approval.

The 2009 I-codes and the 2008 NEC will become effective July 1, 2010.

Code TypeCode ModelAmendment Contact
Building/Dwelling CodeIBC 2009 (Utah Uniform Building Standard Act Rules, Rule R156-56-701)Utah Dept. of Commerce, Div. Of Occup. & Prof. Licensing,(NNN) NNN-NNNNor online
Structural CodeIBC 2009 (Utah Uniform Building Standard Act Rules, Rule R156-56-701)Utah Dept. of Commerce, Div. Of Occup. & Prof. Licensing,(NNN) NNN-NNNNor online
Plumbing CodeIPC 2009 (Utah Uniform Building Standard Act Rules, Rule R156-56-701)Utah Dept. of Commerce, Div. Of Occup. & Prof. Licensing,(NNN) NNN-NNNNor online
Mechanical CodeIMC 2009 (Utah Uniform Building Standard Act Rules, Rule R156-56-701)Utah Dept. of Commerce, Div. Of Occup. & Prof. Licensing,(NNN) NNN-NNNNor online.
Electrical CodeNEC 2008 (Utah Uniform Building Standard Act Rules, Rule R156-56-701)Utah Dept. of Commerce, Div. Of Occup. & Prof. Licensing,(NNN) NNN-NNNNor online.
Fire/Life Safety CodeIFC 2009; NFPA 101 Life Safety Code 2006Brent Halladay
Chief Deputy, Fire Prevention Bureau
(801)(NNN) NNN-NNNNor online
Full Size Image
Applies as a mandatory minimum
Energy CodeIECC 2009 (Utah Uniform Building Standard Act Rules, Rule R156-56-701)Utah Dept. of Commerce, Div. Of Occup. & Prof. Licensing,(NNN) NNN-NNNNor online.
Elevator CodeASME A17.1 2004; ASME A17.1a-2005; ASME 17.1S-2005Utah Labor Commission,
Gas CodeIFGC 2009 (Utah Uniform Building Standard Act Rules, Rule R156-56-701)Utah Dept. of Commerce, Div. Of Occup. & Prof. Licensing,(NNN) NNN-NNNNor online.

Authorities Having Jurisdiction (AHJ)

Authorities Having Jurisdiction are those government officials who are the final authority on questions in a particular area (or jurisdiction).

Jurisdictional AreaContact
StructuralBruce Palmer
Building Official - Structural
Phone:(NNN) NNN-NNNNbr/>Fax:(NNN) NNN-NNNN/td>
PlumbingDavid Webster
Building Official - Mechanical
Phone:(NNN) NNN-NNNNbr/>Fax:(NNN) NNN-NNNN/td>
MechanicalDavid Webster
Building Official - Mechanical
Phone:(NNN) NNN-NNNNbr/>Fax:(NNN) NNN-NNNN/td>
ElectricalWesley J. Greenhalgh
Building Inspector - Plumbing
Phone:(NNN) NNN-NNNNbr/>Fax:(NNN) NNN-NNNN/td>
AccessibilityBruce Palmer
Building Official
Phone:(NNN) NNN-NNNNbr/>Fax:(NNN) NNN-NNNN/td>
Fire MarshalBrent R. Halladay
Chief Deputy, Fire Prevention Bureau
Phone:(NNN) NNN-NNNN/td>
Elevator InspectorXXXXX XXXXX
Assistant Chief Elevator Inspector
Phone:(NNN) NNN-NNNN/td>
MsBabyD :

Here are the numbers it can be done!

MsBabyD :

Your Guide to Building a Gable Shed Roof

A gable shed roof is the easiest to build, and depending on the pitch of the roof, will provide you with some storage space in the attic area. This style of shed roof is one of the most common and can be utilized for building playhouses, garden sheds, utility sheds and more.


Gable Style Shed Roof

gable shed roof
Full Size Image


The following information is provided to you as a guideline and is intended to be used in conjunction with the user checking with local building authorities to make sure all building practices conform to local building codes. Use this information at your own risk.

Remember the pythagorean formula you learned in school?

A² + B² = C²

gable shed roof step one
Full Size Image

A is half the distance of your shed width.

B is the distance from the top of your walls top plate to the inside of your roof peak.

C is the distance between the outside ends of A and B.

Keeping this formula in mind, we can build a shed truss or figure out the measurements of a rafter with a ridge board running down the roof peak.

Here's how to do this.

An Example:

Say your shed is 12' wide.

Given this measurement, then A is 6', or half the width of your shed. This is the measurement of your floor width. This brings up an important bit of info. If your shed is going to be say 12'wide x 16' long. Then the exact measurements of your floor will also be 12'x16'. With this in mind, once you build your floor to these measurements and have erected your walls, the distance from the outside of one wall to the opposite wall will be 12'. And the 2 remaining walls will be 16' from outside to outside.


Example using a shed 12' wide


Now, one other important factor to remember is that you never, never want the pitch of your roof to be less then 15°, unless you plan on going with a metal roof. Shingles at any slope less than this will leak, and leak bad. Water, in the form of rain or melting ice and snow will very easily work its way up under the shingles and down through your roof sheeting, causing much damage. Given the fact that A=6' and lets say you want 5' from the top of your shed walls to your roof peak (inside). This gives us 5' for the loft distance, or B

So, A=6' and B=5', so A (squared) + B (squared) = c (squared) 36 + 25 = C (squared)

C (squared) = 61

C = 7.81'

.81 x 12 = 9.72 or 9 3/4

So, c= 7' 9 3/4

So now we know all the values of A,B, and C.


What do we do now?

Based on the fact that c= almost 8', we are going to at least need an 8'- 2x4 to build this gable shed roof rafter. Better go with a 10' piece because we want to have a rafter tail that will give us a side overhang for our shed.

Take this 2x4 and snap a chalk line down the middle of it on the flat side.


Now on your flat surface, snap or draw a line 12' long. At exactly the middle of this line, (a = 6' )draw a line up perpendicular the distance equal to 'b', or 5'. Now take your chalk line and snap a line from the top of your 'b' line, down to the outside end of your 'a' line. This snapped line will represent 'c'. Measure it. It should equal the number you determined using the equation for the Pythagorean formula.

Now measure 1.5 inches on either side of this line. Do this at the top and bottom and snap lines. This will represent your 2x4 rafter. The 12' line you snapped earlier will represent the top plate of your shed, and the outside corners of this line will be the outside edges of your side walls top plate.


Now we can measure exactly what the measurements will be for your gable shed roof rafter or truss half that will span your shed exactly 12' and give you an inside height of 5' from your top plate to the inside of the top of the truss pieces.

gable shed roof 6
Full Size Image

The following picture shows all the pertinent measurements you will need to cut your first rafter or truss half. You should be able to transfer about 9 critical measurements to your 2x4 for cutting. Once you have the measurements done, you can cut your board, duplicate on a second board, and you will then have a complete truss or 2 rafter halves to nail to a ridge board .


Transferring the measurements to your 2x4 rafter or truss


Make your truss by putting the 2 pieces together on the line you snapped for your top plate. The truss should fit exactly so that the 'birds mouth' sits right exactly where the top plate is.



Add gusset plates and rafter ties to the gable truss



Gable shed roof trusses in place with ceiling joists installed


Trusses are attached to the top plate by using 3-16d common nails toe-nailed from the truss end into the top plate, 2 on one side, and one on the other. Your local building codes may also require the use of hurricane ties for each truss member where it rests on the top plate.


Check your local codes - you may need to
use hurricane ties to anchor
your shed trusses down

hurricane fastener for securing roof rafters
Full Size Image


Building your gable shed roof with a ridge board


The shed roof pictured above shows rafters attached to a ridge board. This can be accomplished with the trusses described previously by cutting off 3/4" off the top end of the truss. This allows you room for the 1.5" wide ridge board. Ends of the rafters are toe-nailed to the ridge board with 3-16d nails.


Gable end supports

end supports for the gable shed roof
Full Size Image

MsBabyD :

I have been looking at codes for about 4 hours. did they give you a copy of this code because I can't find it?


I cannot view the answer because the window is set so small. How do I adjust the view window?

Expert:  Machinc replied 2 years ago.
The code is not that detailed. If you place the sheathing
the owner will not have access to that area from
inside the attic.
. It is easier for the framer to do it
That way.

Such a large area should not be framed
in such a way that it can't be accessible from the

The difference in strength the sheathing would provide
is insignificant .

Machinc, General Contractor
Category: Home Improvement
Satisfied Customers: 765
Experience: Has written home improvement articles since 2008. Earned South Carolina Residential Builders License in 1991.
Machinc and 2 other Home Improvement Specialists are ready to help you
Expert:  Machinc replied 2 years ago.
On another point a dormer or gable framed in that manor
would possibly not have proper ventilation

Expert:  Machinc replied 2 years ago.
Putting the sheathing on would prevent
proper tying in of the gable framing to the main
roof framing.
This can be done when adding to an existing
roof such as in remodeling but cut of the sheathing
has to be done to allow for proper " tying in"
of the framing.

Expert:  MsBabyD replied 2 years ago.
Venting above the sheathing
Vent channels can also be built above the roof sheathing. Builders following this method usually install several layers of rigid foam above the roof sheathing, followed by parallel lengths of 2x4s installed above the foam, each positioned above a rafter. A second layer of roof sheathing is then installed above the 2x4s.

Doing it this way on the roof would prevent any obstruction to the interior

Expert:  MsBabyD replied 2 years ago.
Venting above the sheathing
Expert:  MsBabyD replied 2 years ago.

There are the Utah Codes and sheathing. if this farmer is not a county inspector I suggest you continue But ask a county inspector. Dont mention your building , just ask him in a general way how he would build it.
From what I can see this farmer is butting in your business. But, I gave you all the Utah legal codes on Building Gable Roofing. print them out. and look them up at your county building permit office as research. If you find nothing that holds his remarks to standers then go a head and continue your building Plus they have inside spray sheathing..
Who is the farmer did he stop the construction?




Expert:  MsBabyD replied 2 years ago.
These are the Utah Codes on building ans sheathing. go to your county uilding off office and look it up Dont mention what your doing it look up your rights. If you cant see any codes for building gable roof like the codes I set you. Go to building depatent look up gable roofing as just a curious person dont bring up your current probelm. The go to the building department and look it up again as a party of interst.
This farmer if not on the building commity has no right to stop construction. Only a Building inspector could. If that has not happen. Make sure you have copies of those codes. And continue your opject.'Did you get your windows fixed. Or do I need to make the print smaller for you.
Respectfully Yours,
Expert:  Machinc replied 2 years ago.
Your situation is really getting over complicated.
Building codes cover sheathing thickness and type.
Framing size and length.
Your question was it ok t continue
framing without sheathing the area under the
The answer is yes it is.
If the job was stopped by a person of authority
or the building inspector then you should have
no trouble using all the information
provided by the other experts on this
question to convince them that it is ok to