How To Apply Sheathing To The Roof

• How to choose roof sheathing.

• How to calculate the number of sheets needed.

• How to make Rake.

• How to attach the Rake.

• How to lay sheathing on a roof.

• How to attach spacers.

• How to cut excess sheathing.

• How to install Ice and Water Shield.

• how to install roofing felt paper to sheathing.

1. How to select roof sheathing.

   • Choosing sheathing for the roof is the same as choosing sheathing for the outside walls. The only difference is this sheathing will be thicker at 5/8".

   • Gather information on the various products by clicking on the link above, then choose the product you feel is best for you.

2. How to calculate the number of sheets you will need to cover the roof.

   • Calculate the area of the roof.
     Area = 2(Length X Width) Don't forget to add the dimensions of the Rake into your calculations.

   • Divide the area of the roof by the area of a sheet of sheathing.
     Area of roof / (4' x 8') = number of sheets needed.
     Area of roof / 32 = # of sheets of sheathing needed

   • If your roof is 2016 sq ft, then 2016 / 32 = 63 sheets needed.

   • It's a good idea to buy extra sheets just in case...

3. How to make a Rake for the roof.

   • The Rake extends the roof line past the Gable Ends.

   • The Rake looks like a mini wall. It consists of two 2x4 plates with mini 2x4 studs between them. The width of the Rake should correspond to the size of the overhang you would like.

   • The Rake extends the entire length of the roof ends.

   • Place the Rake at each end of the roof with both ends meeting at the roof peak.

   • Be sure to make your Rake extend past the Gable End the same distance as the roof overhang.

   • Remember that you will have to lift the Rake up to the roof line on both Gable ends and nail it up, so don't make it too long and heavy. Its better to divide the rake into multiple sections and avoid injuries, than to build it in one piece and risk injury.

   DIAGRAM OF A RAKE
   

   How to attach the Rake to the roof.

   • Carry the first piece of the Rake up to the peak of the roof.

   • Line it up even with the roof and attach it to the Gable End by nailing it with Framing Nails.

   • Verify that it is at the same level as the roof line.

   • Repeat this process for the remainder of the pieces on that side.

   • Repeat for the other 3 sides.

   • the Rake also serves as a nailing surface for the roof sheathing, fascia, and Eaves.

   

   How to apply sheathing to a roof.

   • Sheathing is used as a base for a variety of roofing shingles. If you choose to use metal roofing, then you would not use sheathing as a base. Check with your local metal roofing manufacturer for details.

   • Measure 4' up your roof and using a chalk line, snap a line from one end of the roof to the other.

   • Check with the manufacturer of the sheathing as to which side of the sheet should face up.

   • Starting with the lower bottom corner, lay the sheathing onto the trusses and line up one edge of the sheet with the Gable End.

   • Be sure to line up the sheathing with the outside edge of the Rake. Make sure that the other end ends up with at the center of a truss Rafter. If it doesn't, then push the Rafter over until it lines up.

   • Nail along the outside edge every 6" (check your local code for variations.)

   • To locate the Rafters under the sheathing, snap a chalk line onto the sheathing marking the center of each Truss Rafter. This will guarantee that you hit the truss with the nail.

   • Nail sheathing along the lines every 12" (again check local codes.)

   

   • Don't nail the other end of the sheet downn until you have the next sheet lined up. This will enable you to move the Rafter over either way to ensure that both sheets meet in the center of the truss.

   • Insert plywood clips along the top of each sheet in order to receive the next course of sheathing.

   • Continue in this manner until you've finished the first course.

   • The last sheet can be installed whole and cut once the remainder of the sheathing has been installed.

   • You can then use a circular saw to rip the overhanging sheets off at one shot.

   • Start the second course at the same end you started the first. This time instead of using a full sheet to start, you will use a 1/2 of a piece so as to stagger the joints.

   • Staggering the joints along roof will result in a much stronger roof.

   • Depending on the pitch of the roof, you may want to install a 2x4 Toe Boardfor safety, at this point.

   • Line up the first piece of the second course with the outside edge of the Rake then measure and cut the piece to the center of the truss. Nail the sheathing to the outside edge making sure to insert the sheet into the plywood clips at the top of the first course.

   • Continue through the second course of sheathing.

   • Apply as many courses as necessary.

   • When you have reached the final course, you may need to trim the sheets to size.

   • Sheathing between the Gable Ends and adjoining trusses will be fit to the peak of the roof meeting the sheathing from the other side of the roof. However, this only applies to the two ends of the roof peak from the Gable Ends to the first Truss.

   • The remainder of the sheathing needs to be cut about 3" downn from the very tip of the trusses. This will serve as ventilation for the roof.

   • Once you are finished sheathing this slope of the roof, then repeat this process for the other slope.

   How to install Ice and Water Shield.

   • If your winters are below freezing, you will want to install at least one course of Ice and Water Shield. Ice and Water Shield is a self adhesive rubberized material that adheres to the sheathing and protects the edges of your roof from water damage and ice back up.

   • Peel off the backing.

   • Starting at the bottom of the slope, line up the edge of the roll with the outside edge of the roof.

   • Roll out a 3' layer along the entire length of the bottom of the slope.

   

   • The rolls are heavy and the glue is sticky so this process can be a little tricky. Try not to stick it onto itself either.

   • Install a 3' width of Ice and Water Shield on all of the edges of the roof.

   How to install Roofing Paper.

   • The final step of this process is to cover the sheathing with 15LB felt paper.

   • Choose a non-windy day for installation.

   • Beginning on an outside edge at the bottom of the slope, roll out the first course of tar paper overhanging by it 3/8" over the bottom edge of the sheathing.

   • Staple the paper onto the sheathing as you roll it out.

   • Cut the roll off at the other end of the roof.

   • Repeat for each course overlapping the bottom course with the top one. Overlap up to the first line on the paper. This will ensure that any water will roll from the top of the roof to the bottom of the roof without finding its way under the paper.

   • The very top course will overlap the peak by 6". Fold the excess paper over the peak and staple it to the other slope.

   • Repeat this process for the second slope.

     

   • The paper is held down with staples only, and a gust of wind can easily tear the paper off of the roof. Therefore unless you plan on finishing the roof on the same day, you must use temporary precautions to keep it downn until the roofing is applied.

   • Simply nail strips of scrap wood or plywood along the roof running from the bottom edge of the slope to the peak. This should keep the paper downn under normal weather conditions.