Tag Archives: roof underlayment

Sharkskin Ultra

Sharkskin Ultra®

Sharkskin Ultra® is a high-performance roof underlayment for all steel roofing applications over solid decking (OSB – Oriented Strand Board or plywood).


Construction professionals know how important a quality roof system is. This is why so much research, time and effort goes into specifying and installing right roofing products for every home and building.

Sharkskin Ultra® is the original patented synthetic roof underlayment. Designed to ensure quality roof installations are not short changed by inferior “old technology” asphalt felts, or cheap inferior commodity based synthetic roof underlayments. Sharkskin Ultra® is the heaviest, most robust, mechanically fastened polypropylene polymer based product commercially available. Its industry leading high-tensile strength provides the highest tested wind resistance and 12-UV rating available.

Sharkskin Ultra® has a unique patented design using multiple layers of blended polypropylene to achieve:

High tensile strength for durable secondary moisture protection (face it – if water somehow gets through a properly installed steel roofing application, you really do not want it going any further). Plus, if your primary roofing is blown off, it provides a secure secondary water barrier.

High traction non-slip surface for excellent grip and safe walking, even in wet or dusty conditions. Obviously, always use caution and fall protective gear especially in wet weather and windy conditions. There are few things more terrifying than butterflies in one’s stomach as you slide down a roof towards eave edge. In 1988 my Dad was killed in a construction fall off a roof, so I am very sensitive to this one.

Weighing only 50 pounds per 10 square roll (48” x 250’), its light weight makes for faster installations and reduces dead loads on roof systems.

12 months UV resistance, providing long term protection under protracted roofing installations.

ICC-ES, Miami Dade and Florida Building Code approved.

Performs in all temperatures from -40 to 280 degrees F. (Fahrenheit), making it perfect for steel roof installations.

Light grey surface is cooler for installers to work with and walk over than black asphalt impregnated felt. Can be easily marked with a crayon and holds chalk line markings. AS it will not scar or melt, there is no sticky mess like with asphalt impregnated felt (tar paper).

Installs with 3/8” roofing nails, no cap nails required and provides long term nail seal-ability per ICC-ES AC48.

Comes with a manufacturer’s 50-year warranty.

Considering steel roofing over a solid sheathed roof deck? If so, Sharkskin Ultra® might be a design solution to be considered.

How to Minimize Possible Hail Damage

Welcome back from Friday’s article. As a fan of long suffering professional sports teams (Vikings, Twins, Mariners) I had the opportunity to watch Randy Johnson’s epic relief appearance in game 5 of 1995’s ALDS.

Randy also helped Geico sell some insurance with this snowball (not quite a baseball sized hail chunk): https://video.search.yahoo.com/search/video?fr=crmas&p=randy+Johnson+throwing+snowball+commercial#id=1&vid=2f0c9212ab8080ee8ad0b4b53361f2a3&action=click

Randy was clocked throwing a 5.25 ounce baseball at up to 102 mph (miles per hour).  A 1-1/2 pound hailstone will travel at speeds up to 105 mph – basically impacting whatever is in its way with nearly 3-1/2 times the force of a Randy Johnson fastball!

At this point in time, there is no solution providing a completely hail resistant roofing solution. No traditional roofing materials can come away from these types of hail stones without being dented or damaged. While there are suitable measures able to be taken to prevent damages from most hailstorms, largest hailstones will cause damage to even the most durable of roofing systems.

In order to understand how well a roofing material will hold up against hail, it is first important to understand how these materials are judged. A common test for measuring roofing material effectiveness against hail damage would be UL 2218: Standard for Impact Resistance of Prepared Roof Covering Materials. This test uses a steel ball to impact various locations on a particular assembly including edges, seams or unsupported joints or sections. While this test provides maybe a best gauge of how a roof will hold up against a hail storm, a steel ball is not a hailstone, and even this extensive test does not guarantee a material or product will hold up against a severe hail storm.

Fortunately, baseball-sized hailstones don’t happen every day. In a majority of instances, a Class 4 UL 2218 rating will be sufficient in protecting your barndominium from roof penetration due to a hail storm. A Class 4 test involves a steel ball weighing 1-2 pounds being dropped from a height of 12 to 20 feet on an assembly’s same location. This is considered by most professionals (and insurance companies) as the highest level of protection a roof covering material can provide.

While UL 2218 (and other testing standards) measures abilities of a material to stand up to rips, tears, holes and penetrating issues, it does not consider a material’s visual appearance once testing is complete. In other words, your roof may still be 100% structurally sound after a severe hail storm, but could also look like someone took a baseball bat to every inch of your roof. Beyond a visual nuisance, some insurance companies who provide a discount for metal roofing will not cover cosmetic damage caused by hail as your roof is still intact and structurally sound.

 To minimize cosmetic damage, take into account panel design. Many standing seam metal roofs have large, flat surfaces showing smaller imperfections due to their smooth uniform appearance. Breaking up a standing seam panel with striations or ribs will help minimize visual impact of dents, as well as help with expansion and contraction in areas prone to temperature swings.

A common misconception when it comes to protecting a structure against hail damage is steel roofing thickness. While thicker steel can be better at preventing dents and surface damage, provided it is not softer, it is also often less flexible than a thinner material.  Thinner steel panels may dent easier, but are less likely to tear. While most metal panels ranging from 22 to 29 gauge steel offer a relatively similar level of protection, there is a difference in how each thickness will perform against different aspects of a hail impact.

An important factor in choosing a roofing envelope able to hold up to most hail storms includes selecting the right underlayment material. Like visible roof coverings, underlayment materials are also tested for impacts. Often people spend a significant amount of time carefully choosing their roof system covering, without ever considering this second layer of defense. Underlayments can not only help protect your barndominium from impact, but are also tested for water, air and fire ratings.

Ultimately there are a number of factors to consider when choosing a roof to help hold up against severe hail storms. Choosing the right materials and speaking to your insurance company about actual coverage of your plan are among the most important choices to make.

Tips for designing a hail resistant roofing include maintaining a minimum roof slope of 6:12 and/or using roof decking (well supported plywood sheathing) and a tested underlayment.

Do your research – speak to professionals about your options, and make decisions on those factors most meaningful to you and your new barndominium.

Shingles and Roof Slopes Less than 4

Shingles and Roof Slopes Less Than 4/12

I have never felt asphalt composition shingles to be an adequate design solution for any building, much less a post frame one. Some potential post frame building owners look to shingled roofs in an errant idea of added protection against hail (not so, read more here: https://www.hansenpolebuildings.com/2011/09/steel-roofing/).

Asphalt composition shingles are designed and recommended by their manufacturers to be installed on roof slopes 4 in 12 pitch or greater. Therefore asphalt shingle manufacturers base their warranties around this minimum recommended pitch of 4 in 12. For those who don’t understand roof pitch numbers read a more thorough explanation: https://www.hansenpolebuildings.com/2018/09/roof-slope/.

Most manufactures will warrant their shingles down to a 2 in 12 pitch, if following their installation method. Never recommended would be installation on roof slopes below a 2 in 12 pitch.

While every manufacturer will vary just a bit, but all require same underlayment procedure for roofs below 4 in 12 pitch. You have really two choices. First recommended choice would be installing two layers of 15 pound asphalt saturated roofing felt with lap seams offset from one another and all lap seams embedded in asphalt cement. A second choice – install an ice and water membrane throughout entire roof beneath roofing.

Two plies of 15 pound asphalt saturated roofing felt had been recommended application before invention of ice and water membrane. However two ply roofing felt installation procedure are rarely correctly followed. Usually neglected, in order to keep installation time and costs down, would be asphalt cement application of all lap seams. It would be labor intensive to follow a correct application of two layers of 15 pound felt.

Installing ice and water membrane will be more expensive than two layers of 15 pound felt installed without lap cement. In fact, ice and water membrane can cost more than twice of the two layers of 15 pound felt. Made from modified asphalt, ice and water membrane self-adheres, keeps very pliable during cold months and does not become brittle. Because of modified asphalt being used, any penetration, such as nails, will be sealed from water being able to bypass underlayment. Since ice and water membrane self-adheres which eliminates any need to apply lap cement.

In my humble opinion benefits of installing ice and water membrane outweigh alternatives. I want to provide my clients with a cost effective solution without sacrificing roofing system integrity.