Roof shingle exposure distances: this article provides a definition of roof shingle exposure and gives the range of acceptable shingle exposure amounts. Too little shingle exposure may at least cause a cosmetic issue while too much shingle exposure risks leaks or shingle blow-off and wind damage.

Asphalt Roof Shingle Exposure Standards

Definition of shingle exposure

Roof shingle exposure is defined 

as the amount of a shingle whose upper surface is not overlapped by the next successive shingle course or in some roofing patterns, the amount of the shingle that is not overlapped by a side-adjacent shingle.

In our sketch at left, the asphalt shingles are being installed with a 5-inch exposure - the distance between th two red arrows.

Roof shingle exposure amount 

is the portion (measured in inches or cm) of asphalt shingle that remains exposed to weather as successive courses of shingles are installed up the roof slope.

We measure shingle exposure as the distance from the lower edge of an exposed roof shingle or shingle tab down-slope to the lower edge of the shingle in the shingle course (row) just below.

• 5-inch roof shingle exposure: The typical or "standard" asphalt roof shingle exposure amount is 5" or 5 5/8" (metric shingles).
  
  For 12-inch wide shingle materials this means that the head lap or covered portion of each shingle course will be 7".
• 4-inch asphalt roof shingle exposure
  
  On lower slope asphalt shingle roofs with slopes under 4/12 the roofer may use a 4" exposure in order to increase the resistance of the roof to wind-driven rain.
  
  According to GAF,
  
  In some cases, this can be an acceptable practice, but there are risks for which CertainTeed will not take responsibility. A
  
  shortened exposure can harm the appearance of the applied roofing, especially those with shadow lines, and it can reduce shingle ability to resist wind blow-offs by shifting the adhesive seal line away from the bottom edge of the shingles. - "GAF-Elk Timberline ® Prestique ® Grande ® 40 High Definition Roofing Shingles Product Information" (2008) [discontinued product]
  
  See details at ASPHALT SHINGLES on LOW SLOPE ROOFS
• 8 1/4" asphalt shingle exposure:
  
  among some specialty roofing products such as GAF-Elk Timberline Prestique Grande 40, shingle exposure may be 8 1/4" - discussed below.

Exposure Amount for Other Roofing Methods

The allowed exposure amount for other roofing methods and products will vary. For example, in a built up roof (BUR roofing) using multiple plies of tarred felt, the exposure width will usually be defined as the width of an individual felt ply minus 2".

Nineteen-Inch Selvage membrane roofing, also referred to as Double-Coverage or Split-Sheet roofing uses a prepared roofing sheet that includes a 17 inch (430mm) granule surfaced area intended to be exposed to the weather, and a smooth, non-granule surfaced 19 inch (485mm) selvage edge.

Selvage membrane roofing is also referred to as SIS, double-coverage or "Wide Selvate" roofing (ASTM Standard D 371-89, Standard Specification for Asphalt Roll Roofing (Organic Felt) Surfaced with Mineral Granules, Wide Selvage).

Maximum shingle tab exposure amount

The manufacturer's maximum recommended shingle exposure amount varies depending on the shingle brand and model, but a typical industry asphalt shingle exposure amount would be between 5" and 5 5/8" for architectural grade shingles. Some shingle brands permit much larger exposure amounts.

For example, GAF/ELK Timberline Grande® 40 High Definition® asphalt shingles, designed to resemble a wood-shake roof, permit an exposure of 8 1/4" - a feature intended to provide more area of roof coverage per shingle course, thus using fewer total shingles and reducing material cost for the roof.

Adjusting the shingle tab exposure amount near the ridge

Square-tab asphalt roof shingles are normally installed uniformly on the roof with all courses using the same exposure amount, with this exception: when the distance from eaves to ridge would not result in finishing the last or upper-most shingle course with a whole shingle, the roofer may start adjusting the shingle tab exposure perhaps 6 courses below the ridge so that the shingle tab exposure on final course will be a whole tab.

We may stretch or shrink the exposure amount slightly, typically by 1/4" or less per course, to make this final detail work out properly.

Deliberately random shingle tab exposures & widths

In other shingle designs and installation patterns, the manufacturer and/or roofer may deliberately vary the shingle tab exposure amount in a pattern called "random tab shingles". However even when the shingle exposure amount is varied, there will be an upper limit or maximum allowed exposure amount.

Avoid excessive asphalt shingle exposure amount

Watch out: spreading shingle courses too widely apart, that is, installing with excessive shingle exposure may result in a shorter roof life if portions of the shingle head that were not intended for exposure to the weather are in fact left exposed.

Reader Question: is this shingle exposure correct?

8 Sept. 2014 Pam said:

Is anyone familiar with this type of roofing installation? We could be wrong, but it seems as if the rows are too far apart? We would be very grateful for any information or insights. Thanks in advance!

This question was originally posted

at ASPHALT SHINGLE INSTALLATION

Reply:

Pam I took a look at your photo and will also post it here for others to comment. It looks as if there was a deliberate effort to expose a black shadow-line between courses.

I can't know if this is a shingle appearance feature or if the roofer separated the courses by more space than the usual 4-5" of asphalt shingle exposure. Make some measurements and tell us the shingle exposure amount: that is, the distance from the lower edge of a course of shingle tabs down to the lower edge of the successive course below.

If you know the shingle brand and model number that would also be useful.

Watch out: on typical 3-tab asphalt roof shingles, using an exposure amount greater than 5 5/8" risks leaving the shingle nails exposed to the weather - asking for roof leaks.

And as the location of self-sealing tabs (protection against wind uplift) begins at about 6 1/8" up from the shingle's lower edge, exposures in this range may prevent the shingles from self-sealing against wind damage, increasing the risk of shingle blow-off.

Reader follow-up

Thank you so much for your prompt reply! We are considering purchasing the home, and the seller was gracious enough to allow our contractor friend take a look around this weekend before the home inspection this coming week.

He's in excavation and said he knows nothing about roofing, but he seemed to think the courses were spaced a little bit further apart than they should be. I could see if the seller could provide more information on them.

...

The only thing stated in the disclosure is that it was approximately 3 years old. Here are the only other pictures our friend took on the roof. Again, thanks so much for your time assistance! We are very grateful. Any information you would be willing to provide would be very much appreciated.

That way we can compare notes with the inspector we hire, too! Here are links to the other pictures:

Reply:

Your photos show that the shingles are not properly installed in my opinion because at least where you show the plumbing vent,

I can see a shingle cutout that extends over and above the top edge of the plumbing vent flashing (red oval): this will certainly be a roof leak.

It is also an example of inexperienced or sloppy workmanship. Perhaps the roofer was "extending" the shingle coverage on the roof by using wider exposures, thus saving money on material cost.

Measure the distances of shingle tab exposure and compare them with the data we give in our article above.

If you see shingle exposure more than 5 5/8" OR if you see exposed shingle nails or self-sealing tar strips then the shingles were over-extended and most likely will have a reduced life. More, if the shingles were not installed according to the manufacturer's specifications, the shingle warranty will probably not be honored.

If our mutual hypothesis (excessive shingle exposure) is found by measurement and inspection to be correct, then your experience shows that a "new roof" is not necessarily an assurance that all is well, durable, and leak-resistant overhead.

Asphalt Roof Shingle Manufacturers

• Atlas Roofing Corp. www.atlasroofing.com Fiberglass and organic felt shingles
• Certainteed Roofing www.certainteed.com Fiberglass shingles
• Elk Premium Building Products www.elkcorp.com Fiberglass shingles
• GAF Materials Corp. www.gaf.com Fiberglass shingles
• Georgia-Pacific Corp. www.gp.com/build Fiberglass and organic felt shingles
• IKO www.iko.com Fiberglass and organic felt shingles
• Owens Corning www.owenscorning.com Fiberglass shingles
• Tamko Roofing Products www.tamko.com Fiberglass and organic felt shingles

Roofing Materials, Methods, Standards

• Asphalt Roofing Manufacturers Association (ARMA) www.asphaltroofing.org
• Cedar Shake and Shingle Bureau www.cedarbureau.org
• Metal Roofing Alliance www.metalroofing.com
• Tile Roofing Institute www.tileroofing.org

...

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Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2024-03-13 by Tom - Can we decrease the exposure and get a longer life from the 3 tab shingles?

We have a building with a 2/12 pitch. We are looking to replace this roof after 15 years. It was suppose to last 30 years. It started leaking 3 years ago. the shingle exposure is 4 inches. Can we decrease the exposure and get a longer life from the 3 tab shingles? I think we should go to metal for this roof. Your thoughts please.

On 2024-03-13 by InspectApedia Publisher - A 2/12 sloped roof is too low a slope for a successful 3-tab roof shingle installation

@Tom,

A 2/12 sloped roof is really too low a slope for a successful 3-tab roof shingle installation - it's bound to leak as the low roof slope means it's not going to drain rapidly. And if you're in a climate where you get snow or freezing water on roofs, the problem will be worse.

But there is a solution if you want the appearance of shingles: use a continuous waterproof underlayment such as ice and water shield that will seal around the nails. The membrane covers the whole roof and then the shingles are installed over it as a cosmetic upper layer.

Please read details at ASPHALT SHINGLES on LOW SLOPE ROOFS

where we describe how to successfully shingle low slope roofed buildings for slopes from 2/12 up to 4/12, and don't hesitate to ask me follow-up questions.

Thanks for a helpful question.

Daniel

On 2024-03-13 by Tom

@InspectApedia Publisher, Thanks Daniel, we are in northern Illinois. The roof is 66 by 54. The building is used only in the summer
and fall months. No heat or A/C in the building.

According to the last roofer they did put the water and ice under lament under the shingles. I did look at the app you suggested. They mention 4in exposure. Can a 3in exposure work. Would using water and ice along with felt work? Would that be overkill? I will ask our roofers about the felt coverage. Thanks

So many questions, sorry. We are a non profit and budgets are tight. Most of us want a metal roof so we don't go through this every 15 years. You info will help us decide how to proceed for the future. Thanks again.

On 2024-03-13 by InspectApedia Publisher - Changing the shingle exposure may help reduce its leak risk

@Tom,

Changing the shingle exposure may help reduce its leak risk on a very low slope roof. Key is that ice and water impermeable membrane.

The fact that the building is in heated or used in winter avoids the ice dam risk and leak problem.

But you still want a very good and reliable membrane under those shingles.

You don't need to use roofing felt as well.

The membrane is adhered directly to the roof deck.

If the roof is being replaced on the old shingles are being torn off, that's a great opportunity to inspect the old membrane which will probably still be adhered to the roof. You might be able to see exactly where any leaks occurred and have an opinion about why.

The membrane is supposed to seal around every nail that punctures it in the course of nailing down the shingles.

But it could be damaged, or a defective product, or there could be some other shortcoming.

I'd be very interested in what you find at re-roof time.

On 2024-03-13 by InspectApedia Publisher - 2 in 12 could be pushing your luck for most metal roofing products

@Tom,

About going to a metal roof,

2 in 12 could be pushing your luck for most metal roofing products.

I installed a standing seam roof on a low slope roof job but after talking with the roofing manufacturer we made sure to order a version of standing seam product that had an extra tall standing seam connection.

I don't remember off hand but I think that was a 4 in 12 slope roof.

So if you're considering a metal roof product be sure to review with the manufacturer the minimum allowable roof slope for their product.

And if you find one it would almost certainly have to be a standing seam type. That is, corrugated type roof panels would be more likely to leak on a low slope roof like yours.

One more comment:

I understand that you may have a concern about the appearance of the roof, but if that were my building I would go to an EPDM or similar membrane roof that is in fact designed for and does a good job on low slope and nearly flat roofs.

On 2022-02-13 by Chris Moody - were my Timberline asphalt shingles installed correctly?

Hi , Had a roof put on in early Nov. Can someone comment on if this looks like incorrect shingle exposure. I think roofer rushed the job and did a real crappy job.

On 2022-02-13 by Inspectapedia Com Moderator

@Chris Moody,

Let's start with a careful measurement- what is the shingle exposure distance.

And what is the shingle brand and model?

On 2022-04-13 by Chris Moody

@Inspectapedia Com Moderator,
I get 5 5/8 to 5 3/4.
Its not consistent. The shingle is gaf timberline HDZ

Also would you have any concerns on how wavy the shingles look. Almost like they are damaged?

On 2022-04-13 by Inspectapedia Com Moderator - 1/8" variation in shingle exposure won't affect roof performance nor void a roof warranty

@Chris Moody,

1/8" variation in shingle exposure won't itself affect roof performance nor void a roof warranty.

About the wavy surface, were old shingles removed?

On 2022-04-13 by Chris Moody

@Inspectapedia Com Moderator,
Yes this was a tear off and completely new roof. Was done in November but I was assured that was fine.

On 2022-04-13 by Inspectapedia Com Moderator

@Chris Moody,

Two things to look at.

On a November roof in a cool climate the self-sealing tabs may not yet have fully sealed the shingles down. If those shingles that seem to be arched up can be gently lifted slightly off of the shingle below, taking care of not to break them, then that might explain what you are seeing.

Very tightly butted side joints on shingles can also cause a bit of buckling that shows up in warmer weather when the shingles expand.

On 2022-04-22 by Chris Moody

@Inspectapedia Com Moderator, so are you saying this is acceptable or the contractor did not install correctly?

On 2022-04-23 by Inspectapedia Com Moderator

@Chris Moody,

If shingles are buckled because they are too-tightly butted or because of nails not fully-driven that can convert to a roof life issue.

Nobody is going to get far raising a cosmetic issue over variations in exposure in the 1/8" range. That amount of variation is insignificant both cosmetically and as a factor in roof life. And it's almost certainly to be within roofing manufacturer's installation guidelines. (More on that below).

No one can assess the actual conditions of your roof from just the photos and text we've exchanged so far.

That is why I suggested an actual on-roof closer examination of the shingle nailing pattern, shingle side butt-joints, and tab sealing, lifting, curling, or under-driven nails.

By seeking objective data we an avoid an unproductive arm-waving argument with the roofing contractor.

A copy of Timberline's shingle instructions for that product line is at

GAF TIMBERLINE HD-SERIES SHINGLE INSTALLATION INSTRUCTIONS [PDF] (2012)

https://inspectapedia.com/roof/GAF-Timberline-HD-Shingles-Installation-Instructions.pdf

Excerpt:

Position the shingles in the second and subsequent courses flush with the tops of the wide cut-outs. This results in a 5-5/8" (143mm) exposure.

You'll see that the company suggests the roofer snap a chalk line every 6 courses to keep the courses in line, parallel to the eaves, and properly-spaced.
So the roofer is expected to use their eye to align the intermediate courses by setting the exposure of each subsequent course at 5-5/8"

Variations within courses around 1/8" in my opinion will not be considered defective installation by any roofing association such as NRCA nor any shingle manufacturer.

I scanned asphalt shingle installation instructions for several major shingle manufacturers and products: the topic of variation in exposure among or between shingle courses is not discussed - not mentioned - though indeed we've found an occasional roof with such dramatic variation in exposure across a shingle row (several inches) that in those cases the roof was, agreed, not installed in a workmanlike manner.

For example see this

LAMINATE ASPHALT SHINGLE INSTALLATION GUIDE - Malarkey [PDF] -

https://inspectapedia.com/roof/Architectural-laminate-shingles-installation-guide-malarkey.pdf

Our publication of ASPHALT SHINGLE INSTALLATION - best practices by Steve Bliss, former editor, the Journal of Light Construction,

might also be a good read for you.

also

ASPHALT SHINGLE INSTALLATION

which also talks about nailing patterns and shingle exposure.

So what remains is for you or someone in your behalf to check those shingles that are not flat - for the concerns I raised previously.

On 2021-05-12 by harry - find architectural shingle with a 6" exposure.

About 12 years ago a shingle company made a architectural shingle with a 6" exposure.

On 2021-05-12 by (mod) - IKO Shingle Dimensions and recommended single exposure amount

@harry,

In the snippet we post above, using IKO asphalt shingle dimensions excepted from the company's more-complete table at https://www.iko.com/na/pro/building-professional-tools/roofing-101/iko-shingle-dimensions/

you will see some typical current shingle exposure standards including a remarkable 10-inch exposure product.

So the traditional 5-inch exposure is not by any means the only option among current asphalt shingle products. Nor is the 6-inch option.

Key is proper product selection and nailing for your environment, where, for example extra resistance to wind-damage may be important.

On 2020-03-05 by Angela - find 8" exposure shingles

Where can I find 8" exposure shingles for a roof in Florida.
The roofer is unable to find these shingles in Florida.

I'm currently having a leak in the living room and is in desperate need of roof repair.

In anyone know where these shingles are sold, please assist by providing company name and contact info if you have it.
Thanks in advance.

On 2020-03-05 by (mod) - where can I buy an 8-inch exposure asphalt shingle?

Angela:

The standard asphalt shingle exposure is 5-inches. Metric-measure shingles might have 5 5/8" exposure.

If your roof was installed with an 8-inch exposure I worry that it was an improper job from day one. Just adding back over-exposed shingles on such a roof is asking for leaks as well as perhaps voiding any manufacturer's warranty.

[Click to enlarge any image]

Before looking further for 8-inch exposure shingles (perhaps a discontinued product), have your roofer pull off a couple of the existing shingles to make accurate measurements of the product that's already installed.

What is the head-lap of the current shingles?

Were shingles designed for a 5-inch exposure installed within 8-inches exposed?

GAF-Elk did make an 8-inch exposure asphalt shingle as illustrate above and describe here, but you may find it has been discontinued!

Prestique® Grande Type:

• 8 1/4-inch exposure
  
• Laminated asphalt shingle
  
• Colors: Weatheredwood, Sablewood, Barkwood and Antique Slate
  
• 40 Wind warranty in miles per hour: 80-90 mph* (* special nailing requirement)

Note that this is a "High definition" laminate shingle not a simple three-tab shingle. Here are the product details:

• GAF-Elk Timberline® Prestique® Grande® 40 High Definition Roofing Shingles Product Information - DISCONTINUED [PDF] (2008) G8 1/4" exposure asphalt shingles, GAF-Elk Corporation 5/08 1361 Alps Road, Wayne, NJ 07470 www.gaf.com Southeast Sales Office: 813-829-8880

GAF also produced Slateline® and Camelot® shingles that sport a 7 1/2" exposure to the weather and Woodland® that permitted a 6 1/2 to 7 1/2" exposure documented in the ICC-ES Evaluation Report ESR-1475 cited below.

Below: this example chart shows the exposure for some popular Iko brand asphalt shingles with typical 5 1/5" exposure currently available. - retrieved 2020/03/05 original source: https://www.iko.com/na/pro/building-professional-tools/roofing-101/iko-shingle-dimensions/

• GAF-Ca: Discontinued Products, ELK Roofing - Shafter, CA, Application Instructions for Prestique High Definition & Raised Profile Shingles [PDF] 5/14" exposure roof shingles, retrieved 2020/03/05 original source: http://www.gaf.ca/Other_Documents/Legacy_Products_Discontinued/Prestique_Raised_Profile/Prestique_Raised_Profile_Application_Instructions_2.pdf
• "GAF-Elk Timberline ® Prestique ® Grande ® 40 High Definition Roofing Shingles Product Information" (2008) GAF-Elk Corporation 5/08 13 61 Alps Road, Wayne, NJ 07470 www.gaf.com, retrieved 9/8/2014, original source: http://www.gaf.com/Other_Documents/ Legacy_Products_Discontinued/Timberline_Prestique_Grand%C3%A9 /Timberline_Prestique_Grande_40_Info_Spec_Sheet.pdf [OBSOLETE LINK] [Note that this is a discontinued product]
• GAF Materials Corporation, Grand Timberline Premium Architectural Shingle Application Instructions.
  http://www.gaf.com/Content/Documents/20573.pdf [OBSOLETE LINK] discusses the requirements for successful asphalt shingle installation including the condition of the roof deck, the use of roofing felt underlayment, the selection of roofing nails by type and length and penetration of the roof decking, and the role of glue strips on the back side of asphalt roof shingles.
• ICC-ES Evaluation Report ESR-1475, GAF SHINGLE ROOF COVERING SYSTEMS [Discontinued Products] [PDF] (2020 as revised), retrieved 2020/05/05 original source: https://www.gaf.com/en-us/document-library/documents/documents/legacyproductsdiscontinueddocuments/sentineldocuments/gaf_shingle_products__icc_esr1475.pdf

On 2017-04-20 by Lynn

Where can I find 8 - 10 inch exposure dimensional shingles?

On 2017-04-21 - by (mod) - find 8 - 10 inch exposure dimensional shingles?

Lynn, as asphalt roof shingle exposure is typically in the 5-5/8" range, you're looking for trouble not just for long exposure shingles. Above we describe the GAF-Elk Timberline 8 1/4" exposure asphalt shingle line.

On 2016-06-16 by Anonymous

What is the exposure for standard three tab shingles

On 2016-06-16 - by (mod) - What is the exposure for standard three tab shingles

5" or 5 5/8" is the most-common asphalt shingle exposure.

In the article above we answer the question - See this text

We measure shingle exposure as the distance from the lower edge of an exposed roof shingle or shingle tab down-slope to the lower edge of the shingle in the shingle course (row) just below.

5-inch shingle exposure: The typical or "standard" asphalt roof shingle exposure amount is 5". For 12-inch wide shingle materials this means that the head lap or covered portion of each shingle course will be 7".

4-inch shingle exposure: On lower slope asphalt shingle roofs with slopes uner 4/12 the roofer may use a 4" exposure in order to increase the resistance of the roof to wind-driven rain.

...

Continue reading at ASPHALT SHINGLE LIFE / WEAR FACTORS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• ASPHALT ROOF SHINGLES - home
• ASPHALT SHINGLE INSTALLATION
• ASPHALT SHINGLE LIFE / WEAR FACTORS
• ASPHALT SHINGLES on LOW SLOPE ROOFS
• ASPHALT SHINGLE STARTER STRIPS
• BEST ROOFING PRACTICES
• RIDGE & HIP CAP SHINGLES
• ROOFING INSPECTION & REPAIR - home
• SHINGLE EXPOSURE AMOUNT

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