Install Deck Protection & Starter Shingles
Now it’s time to install the roof deck protection. These roof components act as a weather-proofing and protective barrier between your house and the elements, helping keep water and cold temperatures out.
- Drip edge at the eves. Start by laying roof deck protection, or shingle underlayment, over the decking . Use chalk lines to determine where you’ll lay them.
- Using your cap nails, secure the deck protection to the roof. Overlap each row at least 3 to 4 inches. If you live in an area with inclement weather, you should consider using a special leak barrier protector.
- Then, install new flashing and starter shingles at the edges.
- Nail the drip edge in place using your hammer and roofing nails. Always install flashing around a chimney and other valleys where two roof planes meet as these areas are more prone to leaks if not protected.
Tip: When installing deck protection, work from the bottom to the top of the roof.
Shingle Laddering Is Not Recommended
As we discuss in detail
at LADDERING vs STAIR STEPPING SHINGLES,
for ease of installation some roofers install shingles straight up the roof in sets of one or two shingles wide, staggering shingles 6 inches or 18 inches back and forth as shown in our photo and as illustrated in Steve Bliss’s Figure 2-9 below.
Since this lines up butt joints every other course, this is considered a less watertight roof and may leak under extreme situations, such as windblown rain on a low pitch.
Ladder style application of asphalt roof shingles is not recommended by any roofing manufacturers. Manufacturers also claim that shingle color patterns may create splotches or stripes if laid this way.
Racking is another form of lladdering in which shingles are laid straight up the roof in columns just one shingle wide.
DO NOT lay shingles straight up the roof since this procedure can cause an incorrect color blend on the roof and may damage the shingles – Timberline GAF instructions, Op. Cit. We add that it also increases the chances of roof leaks.
Your Decking Is Covered Up By Your Old Asphalt Roof
When you get a full roof replacement, your old roof is torn down to its decking. This gives your contractor a chance to inspect the deckings integrity to see if it can handle your new roof.
If you install a metal roof over your asphalt roof, theres no opportunity to inspect your roofs decking. If your contractor cant test your deckings integrity or inspect for rotten boards, it could lead to a costly problem down the road.
I understand everyone is on a budget, but if youre investing in a metal roof you might as well tear-off your old asphalt roof to avoid this problem.
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Plan The Roll Roofing Job
Plan the roofing job, the job sequence, the purchase of materials, and be sure you have all needed materials on hand before starting the job. The basic roofing sequence is
Stick The Bottom Part Of The Underlayment To The Roof Of The House
Install the second course just like the first, using the guidelines on the underlayment to get the correct overlap. When an ice dam forms on a roof , ice and water can work their way up under the shingles and leak back into the house. Also, strong winds can blow rainwater under shingles. Self-stick roofing underlayment can prevent this because it sticks to the roof decking to seal out water. It also seals around nails, which keeps water from leaking through nail holes.
Rolls of self-stick underlayment have a plastic backing so the material won’t stick to itself. The backing is separated down the middle. Line up the lower edge of the roll with the outside of the drip edge. Peel back part of the uppermost backing on the roll, and nail the top corner of the underlayment to the decking. Start pulling the roll across the decking using the backing, making sure the material is lying as flat and as straight as possible as you pull.
You’ll be able to roll out long sections at a time if you have a low-pitched roof, but the underlayment may slip off the eaves on steeper roofs, so roll out no more than 10 ft. there . It’s important to make sure all your underlayment lies flat before you fasten it to the decking. Ripples and lumps can telegraph through the shingles and may be noticeable from the ground.
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Carefully Flash The Valleys And Seams
Almost 75% of roof leaks occur in valleys where two roof planes meet, or at chimneys or other roof penetrations, so be sure to install roof flashing in these areas prior to the start of the installation. Flashed open valleys may be more durable and water-resistant than blind alleys, in which the shingles overlap from one plane to the other and cover the valley. For asphalt shingles, aluminum flashings are recommended. The metal should be at least 0.019 inches thick.
If working on a roof where someone has already installed flashing, make sure it is in good condition and not leaking. When re-roofing, most pros choose to install new flashings rather than relying on the existing flashings.
How To Install Asphalt Shingles
This article was co-authored by David Bitan. David Bitan is a roofing professional, licensed contractor, and the owner and founder of Bumble Roofing based in Southern California. With over 12 years of construction industry experience, David specializes in restoring, repairing, and maintaining residential, commercial, and industrial roofs. With over 60 years of combined experience, Bumble Roofing provides easy, friendly services to structures including residential, commercial, industrial, multi-family, and government buildings along with hospitals, hotels, and churches.wikiHow marks an article as reader-approved once it receives enough positive feedback. This article received 14 testimonials and 93% of readers who voted found it helpful, earning it our reader-approved status. This article has been viewed 623,859 times.
Installing new shingles yourself can save considerable time and money. You can follow the same steps they do to achieve the same professional look. Re-doing the shingles on your roof can help keep your house in good shape, keep your family safe, and protect you from the elements. Learn to prepare the roof for shingles, lay even courses, and install your ridge shingles like the experts do.
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Asphalt Roll Roofing Installation
Roll roofing is simplest product to install on a small section of low sloperoof is 90-pound roll roofing. This is an inexpensive roofing material often installed by homeowners and do-it-yourself-ers.
“Low Slope” means that these products are installed on roof slopes of 2/12 or more.
Sketch courtesy of Carson Dunlop Associates.
Traditional asphalt-based roll roofing consists of a heavy, asphalt-saturated organic or fiberglass felt with a granular surface.
SBS or modified asphalt mineral surfaced roll roofing membranes are based on SBS, a synthetic rubber that gives improved performance over traditional asphalt-saturated felt.
Watch out: For flat roofs you should not be installing roll roofing but rather you should use a flat roof system such as APP or SBS modified roofing or EPDM – see details for flat roofs at MEMBRANE & SINGLE PLY ROOFS
Traditional asphalt-impregnated felt roofing like that in our sketch above is installed overlapped a minimum of 2-3-inches or overlapped half its width or 16-inches or overlapped 2/3 its width to give a 12-inch exposure and a 3-ply roof, or 3/4 of its width to give a 9-inch exposure and a 4-ply roof.
For asphalt-felt roll roofing, less exposure and more plies = longer roof life.
SBS roofing is commonly installed as a single-ply roof with a 3 1/2-inch selvedge edge overlap.
How Do You Calculate How Many Shingles To Buy
Measure the actual surface area of your roof rather than basing your calculations on the homes square footage. Roof pitch and elements such as gables and dormers will affect the amount as well. Use a simple roofing calculator to get a rough idea of square footage. For a more accurate picture, use a roofing calculator that can take all of these peripheral factors into account or consult with a roofing contractor.
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Pro Tips For Installing Asphalt Roofing Shingles
Asphalt shingles are the most popular roofing material used for residential construction in North America. Roofing and reroofing with asphalt shingles are normally done by specialty roofing contractors, but a homeowner with good skills and who is committed to working safely above the ground can tackle this job. In addition to learning basic roofing skills, you should follow these tips offered by manufacturers and industry pros.
Install The Building Paper
The second step is to install the 15 pound building paper. Building paper can be very slippery so great care must be taken when standing on it.
Roofing paper nails with plastic caps work best to hold the paper without ripping it. Make sure to only stand on places that are well nailed on and also try to always stand on a plastic nail head.
Line the building paper up with the drip edge and install one nail near the corner end. It can overhang the rake and be cut off squarely later.
Roll the paper out along the drip edge. Align it with the drip edge and install a second nail to hold it in place. Go back and install nails every 12 inches along the edges and 24 inches in the center.
The top edge does not need to be nailed because it will be nailed on with the next overlapping row.
Install each successive row making sure to overlap the previous row by 4 inches minimum.
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Nailing Requirements For Laminated Or Architectural Asphalt Roof Shingles
Use 4 or 6 roofing nails in architectural shingles, as shown here.
With laminated asphalt roof shingles, standard nailing is four fasteners spaced equidistant as shown in Figure 2-12, or six fasteners equidistant for heavy-duty installations.
It is important that fasteners go in the designated nail area where they will penetrate both laminations.
Nailing a laminated or architectural asphalt roof shingle too high will leave the bottom lamination loose and subject to slipping out of place.
R905.2.6 Attachment. Asphalt shingles shall have the minimumnumber of fasteners required by the manufacturer.For normal application, asphalt shingles shall be secured tothe roof with not less than four fasteners per strip shingle ortwo fasteners per individual shingle.
Where the roof slope exceeds 20 units vertical in 12 units horizontal , special methods of fastening are required. For roofs located where the basic wind speed per Figure R301.2 is 110 mph or higher, special methods of fastening are required.
Special fastening methods shall be tested in accordance with ASTM D 3161, Class F. Asphalt shingle wrappers shall bear a label indicating compliance with ASTM D 3161, Class F. – IRC 2006 Section R905.2.5
in IRC CHAPTER 9 ROOF ASSEMBLIES
You Wont Get To Replace Crucial Roofing Materials
When you get a metal roof-over, you bypass the tear-off process of getting a new roof. This will save you money, but you miss out on replacing crucial materials that are included in a full roof replacement.
For example, one of these crucial materials is the underlayment. Its your roof systems last line of defense for keeping your decking dry. When you roof over your asphalt roof with a metal roof, you have to rely on the underlayment from your old roof. You also wont get the proper kind of underlayment specifically designed for a metal roof.
Roofing materials arent meant to last forever. Thats why if youre already going to invest in a metal roof, I recommend starting from scratch with clean decking.
To learn more about the crucial materials that are replaced when you get a new roof, read this article on the 9 materials included in your roof replacement.
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Installing Roof Shingles In 11 Steps:
Can You Install A Metal Roof Over Asphalt Shingles
People have been installing metal roofs over layers of asphalt shingles for decades in fact, it used to be common practice and likely would have been considered wasteful in terms of time and energy not to do it. This practice is done less and less with asphalt on asphalt shingles, yet many people still find it acceptable to bury a shingle roof under a metal roof.
There are pros and cons to most methods for home improvements, and roof-overlays are no exception. On the positive side, not tearing off the old asphalt shingle roof when installing metal roofing can save time and money. It can also arguably increase the R-value of the roof and act as an increased sound barrier. On the flip side, not tearing off the additional layers of the current roof increases the load of the roof, void or reduce manufacturer warranties, may impact the aesthetics of the new metal roof, and keep serious construction issues hidden.
Here are the benefits and disadvantages of installing a metal roof over an asphalt shingles roof, along with things you might not have considered and, ultimately, whether you should do it or not.
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What Are Asphalt Roofing Shingles
Asphalt roofing shingles feature a coated base and ceramic granules that reflect the sun, keep your home cooler, and protect your roof from UV damage. While availability may vary, you can usually select between two types of shingles: fiberglass or mat-based shingles.
Fiberglass shingles have a woven fiberglass base coated with asphalt. The baseâs durability reduces the amount of asphalt needed, resulting in lower costs and a lighter roofing product that resists fire for up to two hours. Because of these shinglesâ toughness and long lifespan, manufacturers typically include extended warranties on fiberglass shingles.
Alternatively, mat-based shingles consist of recycled felt paper covered in two layers of waterproof asphalt. Mat-based shingles contain roughly 40% more asphalt than fiberglass shingles, resulting in a thicker, rugged roofing material. Though they may offer greater flexibility, mat-based shingles absorb more water than other types of shingles and can warp.
Deny Replacing Shingles In Extreme Weather Conditions
Introducing roof shingles to renew worn-out ones is competently executed during days when its fairly humid about 55 degrees. The issue with installing new shingles in heated weather is that your sealant will toast out shortly. Make sure to prevent direct sun.
On the other hand, roof shingling in the winter season can result in shingles becoming brittle and liable to break apart. Lastly, resist showers and intense gusts due to safety considerations.
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Shingle Nailing In Areas Of High Winds
For areas subjected to high winds, use six nails as shown in Figure 2-11 or add twodabs of sealant at the bottom of each tab (as discussed
at WIND DAMAGE to ROOFS and as shown in Figure 2-7).
Also special wind-rated shingles with heavier sealing strips are available by special order and may be required in some jurisdictions.
See our excerpt from the 2003 IRC R905.2.5 IRC included just below.
Remove The Old Shingles
- 1.1 – Remove the old shingles and roofing felt with a roofer’s shovel. Pry out nails.
- 1.2 – Sweep the roof as clean as possible and run a scraper over the decking to check for nails that might have been missed.
- 1.3 – Inspect the plywood or particle board and replace any damaged or rotten boards. Panels must be at least ½” thick.
- 1.4 – Nail down or screw in any boards that are raised or loose.
- 1.5 – Install a metal or vinyl drip edge directly on the plywood the length of the eaves. Nail at 12″ intervals and lap each section by 2″. Use snips to cut the corners.
- 1.6 – Verify that soffit and ridge vents are not obstructed.
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Continue Installing Roof Shingles In 6 Row Sets
The eighth step is to continue installing shingles in 6 row sets. The seventh row of shingles will start with a full shingle, just like the first row installed.
Continue following the same 6 row pattern that you did the first time and install the shingles until you get to the roof ridge. The last row of shingles can overlap the ridge if you are not using a ridge vent. If they overlap they can be nailed to the opposite roof.