In this final episode of Breaking Down The Roof, we’re going to cover the installation of the field shingles, ridge cap shingles, and clean up on your new roof.
Row By Row
Now for the most labor intensive portion of the project: the installation of the shingles. To ensure that your roof is around for many years, and serves its purpose of keeping your home watertight and leak free, you need to make certain that the shingles are installed properly. Items such as nail placement on the shingles, depth of the nail, and proper overlap of the shingles are critical. For example, if the nails are not properly lined on the shingle, the shingle will be more susceptible to being blown off, or ripping and sliding down the roof.
Nailing Matters
Professional contractors will typically insist on installing using 6 nails per shingle. While it adds a little to the labor and material cost, it is well worth it. In fact, manufacturers, such as GAF, provide a special wind warranty if the shingles are installed using 6 nails per shingle, as well as their special starter strip. GAF does have the WindProven Infinite Wind Warranty that is available when select materials are installed. This warranty only requires 4 nails per shingle.
It is preferential to hand nail the shingles, however, this is not always possible. Hand nailing allows for the nail to be at a properly embedded in the shingle. If a nail is not deep enough, it will not have the holding power it should, and may back itself out easily. If a nail is driven too deeply, it also will not have the holding power necessary, and will leave an empty space for water to leak through that might be blown under the shingle. Those are the concerns with using a pneumatic nail gun to install the shingles.
There are times where a nail gun is the only reasonable option for installing shingles. One of those is when you have older shiplap decking. The impact of a hammer onto these decking surfaces can cause cracks and splintering, which might not be noticed at that time, but will cause the roof to eventually leak. The same can be said of hand nailing on thin plywood (less than 7/16” in thickness, but with the added issue that the vibration of constant hammering from other portions of the roof can cause of the nails to back themselves out. A skilled roofer will be able to use a nail gun properly, and keep the pressure even.
***SIDE NOTE***
In talking with contractors throughout America, many reputable companies do actually install shingles using nail guns on standard plywood decking. The Houston/SETX/SWLA region seems to be somewhat unique in the application of shingles via hand nailing. Apparently, while they would prefer to hand nail, the labor costs for them to do so are price prohibitive. They, and I, still find hand nailing to be a superior method of installation, so be cautious.
This can also happen if the shingle overlap is too wide, and the nail is exposed. Proper placement is key to providing protection from the rain.
Patterns? Shingles Have Patterns?
Shingles need to have a proper offset when installed so that the roof properly sheds water. A few times a year, I go out to look at projects where the entire roof needs to be replaced after just a few years because the previous contractor didn’t offset the shingles enough (or at all). If the seams align with each other, you will find water penetrating through to the deck.
One of the most common issues for a new roof is that the nails were installed too low on the shingle, which leaves them exposed when the shingle above is installed, and allows water to penetrate around the nail head.
Finishing Up At The Peaks
Once the shingles are installed, we need to put on the ridge caps. If ridge vents are being used, now is when they will be installed. The most common type of ridge cap shingle is a cut 3-tab ridge cap. It is an acceptable low-cost alternative to the premium ridge cap shingles, like GAF’s TimberTex Premium Ridge Cap Shingles.
Most manufacturers have a few premium ridge cap lines to choose from. These ridge caps are pre-cut, which speeds up the process, and usually have additional adhesive on them to prevent against blowoffs. Often, a 3-tab ridge cap will not be considered part of the roofing system when it comes to manufacturer warranty issues, even though it is acceptable in their minimum installation guidelines.
Cleaning Up
The cleaning up process is often the area that causes the most conflict between homeowners and contractors. It is the contractor’s duty to remove the debris, and clean up the property as best as possible. Using a magnet, we are usually able to pick up most of the nails from the yard and driveway, but occasionally we do miss some. (Side note: We removed a roof one time that was installed using aluminum nails. The magnet would not pick up any of the nails, which caused us headaches trying to get things clean.)
We also will attempt to keep your landscaping as intact as possible, but I do recommend if there are any bird baths, statues, or anything of the nature that is on the patio or in the yard where debris might hit it, be sure to move it out of the way prior to the existing shingles being removed. Your contractor might be reluctant to move these items for fear of being held responsible if they are broken in the process.
Final Notes
This series has been a basic outline of a standard shingled roof project. There are nearly always unique complications that arise. Mansard roofs and geometric roofs require special installation techniques, which not every contractor is even aware of. Fortunately for you, I have been there, done that, and learned what I needed to so that I can help guide you through those instances.
Even the most experienced contractors run into issues from time to time, but taking time prior to commencing work on the home will help alleviate many of the headaches.
I hope this has been helpful! Be sure to send me an email with any comments of questions you might have!
Travis Diekmann
The Texan Roofer