Brush Seal Types and Uses

What is a Garage Door Brush Seal?   


If you’ve ever held your hand near the perimeter of a closed garage door without any type of seal, you know that being shut does not equate to being airtight. This is why Brush Seals are an essential part of every residential door and commercial door installation. These entry points are crucial for a business to function day to day, and investing in protection now can prevent future costly repairs.   


Brush Seals are made from strong, densely packed polypropylene filaments that are tightly wrapped around a metal rod or polypropylene spine, depending on the seal. The filaments act as a barrier to prevent debris, dirt, and pests such as rodents and insects from entering your facility. Brush Seals offer additional protection against the elements by blocking rain and extreme temperatures from seeping inside to cut your bills and increase your energy savings.    


Protecting your facility with Brush Seals can ensure a safer, cleaner, and more comfortable facility. Action Industries offers a wide range of Brush Seals that are proudly made in the United States, so you can depend on high-quality parts and maximum protection.     


How do Garage Door Brush Seals Work?    


The densely packed polypropylene bristles of Brush Seals are wrapped around a metal rod or polypropylene spine to prevent them from being pulled out. The dense filaments are flexible and spread out when engaged with a surface, allowing them to seal regardless of potential grooves or dents. This is essential for stopping air infiltration and leakage, which plagues entry points. Such flexibility allows Brush Seals to seal more effectively than blade seals, which can stiffen in freezing temperatures and deform under extensive heat.   


The Brush Seal's high flexible strength is due to the semi-crystalline, synthetic resin polypropylene used in the brush. Polypropylene is known for its light weight, toughness, water resistance, flexibility, and resistance to heat. The plastic is a gaseous compound created through the thermal cracking of butane, propane, ethane, and the naphtha fraction of petroleum. It is a “lower olefins,” which is a class of hydrocarbons whose molecules consist of a pair of carbon atoms linked by a double bond.    


Polypropylene is commonly molded into plastic products with heavy-duty uses. When thin sections of molded polypropylene are flexed repeatedly, a molecular structure is formed that can withstand additional flexing. This is a great benefit that allows the polypropylene filaments to resist pressure and seal up tight spaces.   


Why is air infiltration and Leakage an Issue? 


Air infiltration and leakage is a major problem in most buildings, especially around overhead doors and loading docks. Pedestrian doors and conveyors can also have problem points. Not only can cooled or heated air leak and cause unnecessary utility bills, but drafts can also cause uncomfortable conditions for workers.


Air leakage problems can be compounded by what is commonly known as the "chimney" or "stack" effect. Hot air rises and escapes through openings near the top of the building while cold air is drawn in through door gaps and openings near the building’s bottom. Depending on the temperature, air movement caused by the chimney effect can move up to 10 mph. All of these make it crucial to prevent air leakage through your entry point. 



Are Brush or Vinyl Garage Door Seals Better?  


Brush and Vinyl seals provide similar services, but each has its own advantages depending on what is being installed.    


Vinyl weather seals boast a better aesthetic and array of colors, making them a popular choice for residential garage doors.    


Brush Seals emphasize efficiency over aesthetics and are extra durable, making them a great choice for the irregular surfaces of commercial and light industrial garage doors. Brush Seals can stop 99% of air infiltration and can be up to three times as effective as Vinyl Seals. The soft bristles of the Brush Seal won’t scratch or mark any surface they touch, making them perfect for dock levelers, conveyors, and industrial machinery.   


Our Brush Seals are classified to U.S. and Canadian safety standards by Underwriters Laboratories Inc. for application to hollow metal, steel-covered composite, rolling steel and passenger elevator-type fire doors rated up to 3 hours. All Action Industries brush weather seals are UL Listed making it the perfect choice for use on fire door applications. Commonly used as a Smoke Seal on elevators, Action Industries brush seals are perfect for irregular surfaces and is in compliance with UL10B standards.


Which Garage Door Brush Seal Should I Use?    


While all Brush Seals offer protection, the best choice for you is largely dependent on what use you want to get from the seal. Action Industries carries several sizes and types of Brush Seals in Slim-Lin (fits a #2.5 Channel), Standard (fits a #4 Channel), and 


(fits a #7 Channel). These styles can be used on dock leveler brush seal kits, side seals, passage sweeps, and much more!      

Standard and WeatherBlock Garage Door Brush Seals


Standard and WeatherBlock brushes look similar but serve different purposes. While the Standard seal is perfect for almost every entry point, from home use to business needs, it is susceptible to extreme weather conditions and light leaks from rain. The WeatherBlock seal is identical to the Standard seal but has the addition of a durable EPDM strip sandwiched between the filaments. The EPDM strip takes advantage of the filaments' flexibility and protects your door against extreme weather and leaks. WeatherBlock seals are perfect for industrial and commercial uses, such as food processing facilities, where preventing light and outside contaminants is essential.     


For more information on Standard versus WeatherBlock, see the video below:



Flex Brush Garage Door Brush Seals


While Standard seals are great for smaller jobs, larger orders can be expensive to ship and difficult to install due to their rigid build. Action Industries has negated this issue by revolutionizing Brush Seal transportation with the FlexBrush. Made with non-PVC and 100% recyclable materials, the Flex Brush has a flexible backing made from polypropylene instead of metal. This allows for exceptional flexibility with no lack of quality.    


The Flex Brush is shipped in a reel and easily coiled up to make transportation to job sites simple. Its continuous roll allows for the exact brush length needed to be cut on-site with no scraps, splices, and a reduction in PNs/SKUs.    


The Flex Brush weighs up to 40% less than metal-channel brushes, which is perfect for weight-critical installations and can save you significant amounts in shipping costs. The bristles are incorporated into the seal's base to prevent them from being pulled out, and the material resists corrosion and chemicals.    


Flex Brush is sold by the reel, although Action Industries can send exact footage upon request.


Zebra Garage Door Brush Seals


Zebra Brush Seals are eye-catching, high-visibility markers designed to catch the eyes of workers with their yellow and black stripes, reducing the possibility of car, bus, truck or tow motor accidents. Zebra Seals are perfect for fire doors, barn doors, dock levelers, and any other entry point where visibility is important. 


The Zebra Seal is a stick brush with polypropylene filaments wrapped around a steel rod. The filaments are durable and designed to never hold water or freeze, making them an ideal weather seal for doors in sub-zero environments. The Zebra Brush works with all standard #4 retainers and standard rolling clip-on retainers from Action Industries.     


If these brushes do not fit your needs, Action Industries offers an expansive amount of customizable Brush Seal parts for every job. Be it custom brushes, color brushes, specific materials, and more, Action Industries will ensure you have the right material for the job.   


How to Install a Garage Door Brush Seal


Action Industries makes installation easy with its Brush Seal Kits to save you time and money during ordering and installation.    


Instructions for Brush Seal installations can be seen below:     

  1. Measure the header of the garage door.    

  1. Lay out the retainers end to end. Mark the length of the header onto the retainer.    

  1. Cut the retainer and trim off the excess brush.    

  1. Install the top retainers with provided screws from the installation kit. Start at one end of the header and work your way across.    

  1. Pick a side to measure, taking into account the already installed top retainer.     

  1. Lay the retainers down. Mark the measurement of the chosen side onto the retainer.    

  1. Cut the retainer and trim off the excess brush.    

  1. Install side retainers with the provided screws from the kit.    

  1. Measure the final side.    

  1. Lay out the retainers. Mark the measurement on the last side onto the retainer.    

  1. Cut the retainer and trim off the excess brush.      

  1. Install the final side with the provided screws from the kit. 


When to Replace Garage Door Bush Seals    


When to replace a Brush Seal can depend on a variety of factors, such as the climate and how often the door is used. Generally, a Brush Seal lasts around five years, though some can function up to ten in generous conditions.   


Signs of wear include the bristles being worn, falling out, and a lack of consistency in the seal across the entire door’s platform. Potential draughts can be caught by taping a piece of paper around the sides or top of the door and watching for movement. If the paper moves, air is entering through the seal. Inspecting the door after rain to see if any liquid leaked through will also indicate damage.    


Check your Brush Seal at least once a year to look for any signs of wear and plan to replace the seal at the first sign of issue to ensure your door maintains full protection. Usually, you can just replace the brush and keep the retainer on your door, saving money in the process.     


Action Industries has every part for every door, and our vast variety of Brush Seals is no exception! With no minimum order quantities at checkout and fast shipping, Action ensures that whether you’re renovating your garage or hired to install a commercial door, you can depend on affordable, timely service.

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