Why Navail Magnetic boot?

Grip is key for roofing. Whenever the pitch is high enough, a roofer needs to choose the right footwear to maximize traction. Of all the types of roofs, steel roofs are among the most difficult because of how smooth they are. Roofers sometimes use baskets shoes or sneakers because their soft and flat sole offers a decent grip. 

However the most grippy shoes for steel roofing are with no doubts magnetic shoes. I terms of traction, the difference is just night and day. Now the magnetic shoes also come with their drawbacks. 

I the design process of the Magnetic boot by Navail, a close look was taken at the prior art. More specifically the Steel Walker II® from Cougar Paw® was tested. That company has developed the Steel walker I® before creating the Steel Walker II®. The general principle is the same. Round magnets are placed in cavities made in the sole. Then the sole is glued and stitched to the vamp. The main difference between the Steel Walker I® and the Steel Walker II® is that the Steel Walker II® has a softer rubber and a different thread pattern to maximize the grip. Before I deep dive into the improvements I felt were needed, I want to thank Cougar Paw® for providing the American roofers with a magnetic footwear. It has been the only magnetic roofing shoe available in the US for years.

The main issue with the Steel Walker II® for us was the durability. Stepping a single time on a screw head or on the edge of a metal sheet was an almost certain way of destroying the shoe. In fact the magnets are only held in place by a thin layer of rubber beneath them. Pierce this layer even slightly and you create a weak point that will grow quickly, tearing the outsole. Unlike a regular footwear, in a magnetic shoe, you have got magnets that are strongly attracted to the steel roof. This pulling force is the one that works to enlarge any hole around a magnet. The larger the initial damage, the quicker the outsole will break and release its magnets. This is even quicker when roofing on a hot day. A steel roof can get pretty hot (as hot as 140°F) just by being exposed to the sun. Heat softens the rubber and makes it weaker. For non magnetic roofing shoes, this is a good thing since a softer rubber offers more grip. For the Steel Walker II®, the drawbacks of heat greatly outweigh the benefits. In our experience, we lost the first magnets on the second day of use. Using a magnet from a magnetic shoe might seem a minor thing since they are other magnets in the sole. It is not. The loss of traction is sudden and unsettling. Even an experienced roofer can get surprised, trip and start sliding. This happened in our trial. The roofer was so disturbed by this experience that he was scared of getting back to the roof for a few days. The thing is, it is so easy to step on a sharp object such as a screw head that you can quickly loose confidence in your magnetic footwear. 

The second area of improvement of the Steel Walker II® by is the construction itself. Glueing and stitching is generally a good practice. However the glue has a tendency to soften with heat and use. Then only the stitching is holding the sole and the vamp together. That would not be an issue if the stitching was all around the sole. Unfortunately if a roofer pick the option with a composition toe, that magnetic boot does not have stitching in the front. In fact the composition toe would have to be pierced to allow stitches to go through it. Probably for that reason, Cougar Paw® also offers an option without composition toe where the stitching is all around the magnetic shoe. Of course, it is no longer a safety shoe as your toes has no protection against something falling on them. As a roofer sometimes needs to handle heavy material or just his or her tools, there is a significative risk or foot damage when doing roofing, like any other construction work. Therefore, with the Steel Walker II® from Cougar Paw®, a roofer has to choose between lack of safety for his feet or having the sole splitting apart from the vamp as it happened in our testing after about a week of use.

The third area of improvement we identified for the Steel Walker II® is comfort. At first, this magnetic footwear is comfortable. However, things change when roofing on a pitched roof. In fact what happens is your ankle is flexing to compensate for the slope. Cougar Paw® does not provide a heel on their magnetic roofing shoes. Therefore it is as uncomfortable as using sneakers when it comes to ankle comfort and more importantly, heel comfort. Indeed, when the roofer is facing the slope (which happens most of the time), their heel rubs against the back of the magnetic shoe. It feels like all your weight is being hold by your heel and at every single step, it is rubbed. As an experienced roofer, you might be fine for the first hour maybe but at the end of the day you are definitely relieved to remove your magnetic shoes and not so eager to put them back on the next day.

The fourth area of improvement is magnet longevity. That sounds weird at first as a magnet can normally be used with no issue for about 300 years. However after a while one of the pair we used for the trial has lost a great deal of its pulling force and therefore of its traction. Our working theory is heat deterioration. A standard neodymium magnet should not be exposed at temperatures higher than 140°F, which is about how hot a roof can get. Exceeding this temperature is fairly easy in a normal routine. Just place your magnetic shoes in a car or a truck by a sunny day windows up and you are sure to have them exceed this temperature. Well, I mean a sunny day in a place like Texas, Florida or Arizona, not Canada or Greenland. Anyway this pair of Steel Walker II® was the last still functional of the three we used for this initial trial. At least it still had its magnets in. Of course with this loss of traction, it wasn't that useful to have them on a steep roof. Especially a steep corrugated steel roof.

The fifth area of improvement is protecting the feet from nails. The Steel Walker II® outsole is very thin and easy to pierce and the midsole is a sort of hard cardboard. Nothing would resist a nail if a roofer were to accidentally step on it. If you were to step on a nail, you would better hope it hits the magnet as it would block it. But then you would have just made a hole in the weak part of the sole. You should expect to loose a magnet anytime soon.

Last but not least, the magnetic boots from Cougar Paw®, as any magnetic shoe on a work site, would pick debris. Pitched roofs are relatively clean as debris fall of with gravity. However, as soon as the roofer steps foot on the ground, they will take back all these debris. All sort of nails, staples, or rusted pieces of steel sheet would be attracted by the magnetic sole and stay there. Now to remove them, the roofer has to take the shoes off and use a cleaning magnet. Cougar Paw® does provide a sole protection to enable roofers to walk on the ground while wearing their Steel Walker II®. With this cover, the magnetic footwear is protected and removing it should detach the ferrous debris. However, there is no way that a man, a woman or even Spiderman could put this sole cover without taking off the Steel Walker II® first. You need at least two hands to install or remove it and you need to have the sole facing up. So basically when the roofer comes down from the roof, he or she needs to remove both magnetic shoes, then spend one more minute to install the shoe covers, put back the magnetic footwear on and only then can he or she grab the tool one needed. Alright and now it's time to climb back on the roof. Remove the Steel Walker II®, spend another minute removing the sole covers, put back the magnetic shoes on and get back to work. Well, needless to say that we did not use them a lot. It seems more efficient to have two pair of safety shoes; a magnetic safety shoe and a regular safety shoe when walking on the ground. This way, you do not have to put or remove the sole covers. 

So, with all the in mind, we took 4 years to come out with a solution to all of this. It might sounds like an improvement but the technology is fundamentally different.

In the Navail Magnetic boot, the magnets are not hold in place by the rubber beneath them but anchored to a steel plate above them, deep into the rubber sole. Our sole is plain, not hollowed to allow for an increased structural strength. 

Cutting or pricing the sole below the magnet has little impact as the rubber is molded on the magnet. This construction creates a strong bond between rubber and magnet. There is no room for tearing expansion. Have a look at this video to see how the Navail Magnetic boot handles cuts.

To remove a magnet from a magnetic shoe by Navail, one would have to cut a circular hole all around the magnet then use some sort of clippers to hold it firmly on the sides then pull hard enough to surpass the magnetic force that anchors the magnet to the metal anchor within. Let us just say we haven't thought of a situation where this would happen on a work site.

Not only the construction is different but the material is also higher quality. We use a high performance rubber made in the US. It resists far more hits and abrasion than most rubbers and it comes with a high grip too.

Instead of gluing and stitching, we mold the sole directly on the vamp. This way the bond created is better than that of any glue and there is no need for stitching. We are not trying to bond two things together, we are making the whole magnetic shoe as a single piece.
Thanks to that construction, we are able to offer a steel toe boot in all our magnetic shoes, with no compromise on durability.

When it comes to comfort, instead of just using comfy, breathable and padded materials, we also thought about the foot positioning. The smaller the ankle angle, the more comfortable the magnet boot would be after a day of roofing. Therefore, we placed a thick damper under the heel. First, it absorbs shocks and spares your skeleton from a few useless vibrations. Two, it makes your heel higher which allows you to feel less of the roof steepness. There is less pressure on your ankle and you feel much less weight on your heel.

Now about the magnets durability, we use higher quality grade magnet. You could put them into boiling water and they would not be affected. We do not recommend doing so though as your feet might get wet when you put your magnetic shoes back on.

Since stepping on a nail on a worksite does happen, we placed an anti-perforation midsole under the feet. It covers the whole foot. The midsole we use is lightweight and flexible at it is made of para-aramid fibers (Kevlar® material). It is certified ISO EN: 12568:2010 and GB/T21147-2007. This means it has been successfully tested in a lab against nail perforation.

As you need the most traction when you are on a steep roof, Cougar Paw® was right to offer sole covers to protect the sole when walking on the ground. We just made it easy to use. Instead of having to remove your magnetic shoe and then use all your strength to force the sole cover on, we use a hands-free approach. Simply step on our magnetized sole cover and it snaps itself onto your magnetic shoe. No need to use your hands or even bend. To remove it, just step on the back of your sole cover with the other foot and lift your magnetic footwear. It peels right off. Due to its construction, the magnetized sole cover acts as magnetic shield and prevent debris from being attracted to the magnetic shoe.  Less debris picked up means less debris to protect from and potentially to clean.

Fixing the main flaws of the Steel Walker® was not enough. We also wanted to put performances to the next level. With its specific construction, the Navail Magnetic Boot uses the most of the magnetic strength the magnet can provide. The magnetic field is controlled in order to be stronger close to the sole and weaker away from it. There is no need to attract pieces of iron few inches away but there is a need to firmly hold the roof when the roofer steps on it. First, this allows for an easier walk as the effects of magnetism are not felt when walking until the sole touches the roof. We call it "Walk & Lock". Two, the resulting traction is higher. Much higher. In our testing, we measured the grip from the Navail Magnetic Boot and compared it to the grip from a Steel Walker II®. The Navail Magnetic Boot had three times more grip than the boot from Cougar Paw®! That's a 200% increase! You can take a look at this video to see the traction test. For a lot of jobs, the grip provided by the Steel Walker II® is probably enough. However, if the roof is too steep, if it is a bit dirty or wet  or if it is made of galvanized steel, the traction lessens rapidly. At Navail we believe that since one cannot foresee the future, we need to make sure to prepare you the best we can for what you might encounter.

To conclude I would say that using sneakers or basketball footwear can work in some conditions. However, the grip you get is limited and there is no protection for your toes or against nails. The next good move a roofer can make is to use a magnetic footwear such as Steel Walker® from Cougar Paw®. However, the durability is limited and you are at constant risk of suddenly loosing a magnet and the associated traction. Plus it is not easy not to pick up debris. Therefore, the best move a steel roofer can make is to go for the Navail Magnetic Boot. This way, the durability is increased, the debris is more easily handled, the comfort is higher and you get up to three times more traction. I am not saying using Cougar Paw® magnetic shoes is bad as it better than using sneakers in some regards. What I am saying is: "why use a rolling phone when you can have a smartphone?"