Avoiding Visible Seams in Artificial Grass Installations
The Most Recognized Problem in the Synthetic Turf Industry Today
In this last year I have traveled across the nation assisting contractors in repairs and installations of synthetic turf seams. Whether it be residential, commercial or sports fields, seam problems have become a growing epidemic. Contractors are pulling their hair out because their seams are either visible, ruptured or installed improperly. I am often asked “What do I do to ensure that the seams will be undetectable and withstand the test of time”?
This month I will get in more detail regarding seam problems and how to acknowledge where they come from and how to prevent them. I will also teach the basic understanding of the Superseam Tool and its method which will allow your installation of seams to be effortless.
Terms to Remember
Seam- Any line formed by abutting edges.
Seam Separation – Separation of two sections of synthetic turf that are seamed together.
Seam Rupture– The breaking or bursting of two sections of synthetic turf due to thermal contraction, wear or manipulation by physical force.
SGW Superseam Pro Adhesive- the Industry’s #1 Synthetic Turf Adhesive
Cohere – To stick together; be united; hold fast, as parts of the same mass
Scrim: the backing of a synthetic turf roll that extends beyond the fibers of each side of the roll
Gauge: an outline of rows of tufted fibers stitched into the backing of synthetic turf rolls.
Synthetic Turf Thatch– Textured yarn situated below the face yarn to enhance recovery of fibers when wear becomes present.
Synthetic Turf Mohawk- When two sections of synthetic turf are joined together, the fibers formed a ridge causing a visible line to be present.
Superseam Tool – A patented aluminum template designed in a convex/concave “S” shaped pattern to make synthetic turf seams undetectable.
Subgrade Soil Stability: the underlying soils being of quality, firm and steadfast
Compaction: An increase in the density of something
Gauge: an outline of rows of tufted fibers stitched into the backing of synthetic turf rolls.
Dense Yarn/Fiber Pressure: Increase in density of yarn/fiber creating pressure
Synthetic Turf Seam Integration: the action of forming two sections of synthetic turf together to unify as one
Seam Reflection: the dynamics of light (sunlight) creating the connected seam to be visible
Adhesive Seam Compression: pressure that is applied to seaming area of two sections of synthetic turf onto adhesive glue and seaming tape
“Understanding the components of synthetic turf that is being installed is the key to every successful installation especially when it comes to seaming” – JW
Inspecting the synthetic turf that you purchase is the first step in having a successful seam installation. This does not mean that the turf is defective. It is a common practice in being successful. Inspecting the edge of the roll will allow you to decide how many gauges that you will need to cut in away from the scrim edge. A majority of synthetic turf backing becomes thicker within a few gauges in, away from the scrim. (Factory flange that is removed).
Please note: The gauge width dimension is from fiber row to fiber row, so when you are seaming the two sections together, you are connecting them per the manufacture’s gauge dimensions. You can find the gauge specifications for each product on the Synthetic Grass Warehouse web site as well as their particular spec sheets.
Make sure you acknowledge the measurement between the gauges before you remove the scrim. If the synthetic turf is manufactured with a 3/8” gauge width then you will want to connect the two sections of the turf together and keep the 3/8” gauge width during the entire seaming process. If the synthetic turf is manufactured with a ¾” gauge width, then you will want to connect the two sections of turf together and keep this ¾” gauge width during the entire seaming process. This ensures accurate integration without the seam being too close or too far apart. If the distance between the fiber rows is spaced too wide, not only will the seam be visible, but it will also become very noticeable once you place your infill materials into the synthetic fibers.
Take a sharp turf/carpet knife and cut between the second or third gauges from the edge “Scrim.” Change out the cutting blade every 20 feet to ensure a clean cut. Do not cut into the fibers or too close to the fiber row, as this will cause the fibers to fall out from aggressive foot traffic. By cutting two-to-three rows in from the edge of the scrim, this will give the new seam integrity, strength and a fresh edge.
If the distance between the fiber rows is spaced too wide, not only will the seam be visible, but it will also become very noticeable once you place your infill materials into the synthetic fibers.
Leaving too large of gap between the two sections of the seam will cause the seam to be noticeable. When connecting the two sections of turf together and a gap that is larger than the manufactured gauge is installed, the seam will allow more infill to lay within the seam line which will cause it to be recognizable and you will have to re install the seam.
Cutting the seam fibers can cause the seam to be visible. When cutting the edges for a seam you must be careful not to cut any fibers. Making these mistakes by cutting fibers at the seam causes more infill to lay within the seam line and you will have to re install the seam.
RULE OF THUMB: It is always recommended to secure and install the seam first prior to cutting the edges and completing the rest of the installation process. Synthetic turf has a tendency to move due to heat transfer and could cause the seam to separate throughout the day.
When both sections are placed together at the proper seam width, secure both sections with spikes, nails or staples approximately 18 inches on both sides of the seam. This will prevent both sections from moving while constructing the seaming process and will allow both sections to be folded over for placement of seaming tape. DO NOT FORCE NAILS, STAPLES OR SPIKES ALL THE WAY DOWN FOR THIS PROCESS! THIS IS TO ONLY SECURE THE SECTIONS OF TURF SO THEY DO NOT MOVE DURING THE SEAMING PROCESS.
NAILING SEAMS WITHOUT GLUE: Securing the seam with nails or staples could make the seam more visible due to manipulation. I highly recommend using the seam tape and glue/adhesive method. Using this method you never have to worry about the seam being manipulated or damaged by nails or staples. Always remember: The larger the head of the nail, the more visible the seam will be. Make sure to spread the fibers to allow the head of the nail to pass through the fibers to the base of turf backing or your will create divots by trapping the fibers with the nail heads. This must be a common practice on every nailing procedure. If the installer’s preference is securing the seam with spikes, staples or nails down the seam edge I recommend doing this in a “stitch” pattern.
Too many nails or staples that are placed at the seam will manipulate the fibers and cause the seam to be noticeable. If you are going to use nails to secure the seam I recommend using a nail that has a head that is equivalent in size of the gauge of the turf you are installing. This will allow the nail to manage its way down in between the gauges. Example; if the gauge is 3/8” wide then you surely would not use a nail that has a head larger than the gauge width. If the nails are placed too far in from the seam this will cause the edge of the seam to flip up and will definitely make the seam visible. If the nails are placed too close to the edge of the seam this will allow too much infill at seam line and will be noticeable. This is why I recommend using the seam tape and glue method. The seam tape and glue method does not require any manipulation due to nails or staples.
If you are using staples you must understand the sub-grade conditions. Using staples in hard, rocky areas can cause the staple to bend outwards and cause the seam to separate. (Notice the pictures above of staple width after being placed in these type of conditions)
1. There are three visual inspections to every staple that is placed to prevent trapping of the fibers. 2. You have two spikes on the staple that you must clear fibers from. 3. You have the crown of the staple that you must clear fibers from.
When installing staples you must constantly inspect the seam width during the seaming process. This will ensure that the staple does not pull apart the seam if it is subject to hitting rocks, or hard soils.
If you have an installation that the seam was pulled apart due to staples, this is my recommendation for the repair.
Vacuum out the infill on both sides of the seam. This will allow workability for the seam to be opened, inspected and joined back together. Place the seam together and secure the seam on each side with Nails approximately 18” away from the seam. I have instructed some contractors to temporary tape the fibers back with an adhesive tape to be more accurate in repairing the seam. Open the two sections to be seamed and place SGW seam tape at the center of seam and secure. I recommend using a 1/8” trowel when placing adhesives to synthetic turf seam tape. This will place the adhesive evenly on the seam tape to prevent the excess to seep up and through the seam. Use the 1/8” trowel and place SGW Superseam Pro adhesive onto seam tape. Connect the two sections always inspecting the connection width to make sure it is placed tightly together. Place 50lb bags (SGW Infill bags are 50 lbs) on top of synthetic turf center of seam for compression of adhesive. These steps will prevent any manipulation of fibers and create a strong undetectable seam.
SEAM TAPE & ADHESIVES
When both sections of synthetic turf are secure and the seam is perfectly in place, fold open both edges of the two sections to expose the subgrade. Place SGW seam tape down the center of the seam and secure with spikes, nails or staples. This will prevent the seam tape from rippling while placing the glue. **Please note: SGW seam tape is manufactured with a plastic film on one side. This side should be face down and resting on the subgrade materials. The plastic film prevents moisture coming up through the seam tape, which may cause failure. **
Roofing Repair Tape is NOT! Made for synthetic turf seams. Many contractors are using this economical, fast roofing repair tape as a synthetic turf seaming tape. Roofing Repair Tape is not manufactured or tested as a Synthetic Turf seam tape. It does not have the ability to successfully cohere two sections of synthetic turf together. The pictures below show that the roofing repair tape only touches the exterior of the gauges and does not reach up and between the gauges to the backing. I personally have witnessed hundreds of seam failures that were seamed together with roofing repair tape. You can easily pull the seam from the tape months after the roofing tape has been placed. I recommend to never use this as synthetic turf seam tape.
Superseam Pro Adhesive is a single component Urethane adhesive. It is the professional’s choice of synthetic turf glue adhesive. Its adhesion strength has been tested against its competition and outperformed them all. In fact it averaged 200% stronger then the leading competitor. Superseam Pro Adhesive has excellent shear and elongation properties, along with its ability to withstand harshest weather conditions with great longevity. Superseam Pro Adhesive can be used indoors or outdoors with proper ventilation. Superseam Pro Adhesive has many uses in the synthetic turf and carpet industry including “Glue Down” on exterior surfaces as in concrete, pavers or clean asphalt.
• Superseam Pro Adhesives are manufactured in the U.S.A with no pigments. Pigmented adhesives can be a concern for staining surfaces that are other than its use. • Excellent water resistance. • No foaming through seams at high temperatures. • Excellent Freeze Thaw Strength and longevity • Much thicker viscosity than other leading adhesives on the market today. • User friendly and workable cure times. • Great adhesion and superior strength in heavy traffic areas. • Superseam Pro Adhesive can be used in Synthetic Turf Glue Box applications. • Bonds to Wood, Concrete, Clean Asphalt Paving, Fiberglass Seam Tape
• Superseam Pro Adhesive coverage rate varies upon substrates surface condition. • When seaming synthetic turf 12” Seaming tape the coverage rate is approximately 50 linear feet per gallon (12” wide spread at 1/8”using the Superseam Trowel). Thicker applications are up to the professional.
Superseam Pro has been tested and maintained its strength under water during its curing process to ensure its stability and bonding strength. This test ensures its longevity during harsh wet climates.
Superseam Pro withstands freezing temperatures and remains strong and flexible in addition to preventing seam rupture, even during the hottest days.
I strongly recommend placing the Superseam Pro Adhesive on the seam tape early in the morning or late afternoon to prevent yarn shrinkage. The heat of the day will not only cause the seam to expand and contract, it will also cause the synthetic turf glue to set up too quickly or bubble/seep through the seam. You may learn more about yarn shrinkage on the SGW website.
Too much Seam Adhesive can affect the seam and its fibers integrity. Placing the wrong adhesive especially in the hot summer months can cause the adhesive to seep up through the seam line and stick to the fibers making the seam visible. Using moisture cure adhesives that creates excess foaming properties can also a cause seam failures, I recommend NOT using these. Excess foaming causes the seam to lift, creating noticeable seams. I recommend using Superseam Pro adhesive which does not foam and can be used in harsh weather conditions.
When your seam integration is complete I recommend placing infill bags or weight (no heavier than 50 pounds) on top of the seam after gluing for approximately 30 minutes. This will allow for proper compression to allow adhesive/glue to reach the entire backing between the gauges/stitch rows.
Final Inspection of the seam throughout the seaming process is very important, especially in hot summer installations. The heat may cause the synthetic turf to expand and contract which will cause the turf to move. After the Adhesive/Glue is placed, inspecting the seam while connecting the both sections together will allow the installer to make adjustments to ensure the seam is tightly seamed together. When applying adhesive on days with higher temperatures, always inspect the installed seam throughout the curing process. This will prevent the adhesive to bubble/seep up through the seam and drainage holes. Just because your seam is glued and you have other tasks to complete the entire installation does not mean you avoid final inspection of the seam.
Improper Subgrade materials under the seam construction can cause the two connecting sections to have different elevations causing the seam to open up. Placing infill to this seam thereafter causes the seam to separate revealing a line of infill. Prior to adhering the two sections together make sure the subgrade compacted and is neat, smooth and free of any gravel. I recommend the top layer of materials below the turf be of DG, Chat or a mixture of fine sand and small gravel. If gravel or large stones are present, you are asking for trouble and will surely be returning to do repairs.
Subgrade Soil Stability and its Involvement to a Successful Seam: It is very important that soils or grading materials that are placed under the synthetic turf be of quality and can reach approximately 80 percent compaction. Compaction is accomplished by vibrating, tamping and rolling the sub-base materials. This establishes a solid base in which to drive the nails while installing the turf. Common failures to seam ruptures are caused by underlying soils not being of quality, form and steadfast. Substandard subgrade materials that are unstable cause the underlying subgrade to expand and/or contract. For Example: Soils that have extensive water intrusion, expansive properties, high in fines, low in aggregate, will cause instability. This may cause the seam to move and separate.
Too much Infill pushed into a seam can cause the seam to be visible. When large amounts of infill is placed at a seam it will trap the fibers and cause the seam to part leaving the seam line visible. I recommend hand filling the seams to perfection then complete the entire project by drop spreader. This will lessen the chances for visible seams.
Using improper seam tape will cause seam rupture and cause the seam to be visible. Most seam ruptures are caused by seam tape that is not of quality. If the adhesive and synthetic turf is not able to cohere properly to the seam tape this will cause future seam failure. Note; Drywall seam tape is not to be used seaming synthetic turf together.
Placing synthetic turf seam tape improperly is another reason why seams fail. SGW Synthetic Turf Seaming tape is manufactured with a plastic film on one side. This film side MUST be faced down against the compacted underlying subgrade materials. This plastic film protects the seam and its adhesive from ground moisture. If the plastic film side is placed up and adhered to the backing of the synthetic turf the seam will pull apart and will have to be reinstalled properly.
It is important to secure the placement of the seam tape directly in the middle of the seam to ensure equal adhesion and placed tightly against any hardscape areas. This will assist in the strength of the seam and its integrity for years to come.
Trimming of the fibers at the seam location may be needed. Sometimes when seams are cut, fibers may be pulled up and cause the fiber to be higher than the other surrounding fibers. Using a pair of scissors carefully trim the elevated fibers.
Excessive Power Brooming/Fibrillating causes “dulling” of the fiber. When the fibers at the seam are over brushed it leaves scratches on the fiber which allows a different reflection from sunlight. The “dulling” of the fibers usually causes the over brushed seam to become darker in color.
“Both contractors and homeowners get so frustrated when their hard work is upstaged by seams that are visible due to the Mohawk.” – JW
The Mohawk is a result of pressure. A majority of synthetic turf manufactured today has “Thatch” fibers integrated between the turf fibers. These “Thatch” fibers are tufted within the primary fibers which allow them to stand upright and prevents premature matting. When the scrim (flange at the edge of the roll) is removed, the pressure of the fibers push outwards. When the two sections edges are joined together for the seaming process they push into each other causing the dreaded “Mohawk”. The Patented Superseam Tool and its method causes the “Dreaded Mohawk” to disappear.
The picture above demonstrates how one piece of synthetic turf was cut by using two methods. One method was a Superseam cut, and the other a straight seam cut. When the sections were connected together the straight seam cut caused a visible line which I have named the dreaded “Mohawk”. This patented Superseam and its design creates a concave/convex edge which allows the fibers to integrate within each other.
Q: What is the Superseam Tool made of? A. The Superseam Tool is made of high strength Aluminum, which makes the Superseam light and durable for many uses. Its dense quality allows cutting blades not to grab while sliding down the Superseam Tool.
Q: How much waste is left after using the Superseam Tool? A. When used correctly, there is approximately 3″ inches of waste on each section of turf. “Very cheap compared to a visible seam and a bad reputation.”
Q: Should I use the Superseam on every seam installation? A. The more you use the Superseam Tool the better you will get. The main objective is never having to go back because your client is unhappy with visible seams.
Q: What are the offset marks in the Superseam Tool? A. The offset marks allow the Superseam tool to integrate into one another. The offset mark is usually used at the exterior edge of turf normally at the hardscape, curbing or pavers.
Q: How do use the Superseam Tool up against a curb or wall? A. You will have to fold the turf back and remain on the snapped chalk line as per the instructions.
Try the New Superseam Putting Green Tool!
The new patented Putting Green Superseam Tool is now available. It comes in 6 foot lengths and its unique shape is designed for putting greens to create flawless seams.
Synthetic Putting Greens expand and contract more than regular synthetic turf grasses which cause separations in seams. The Putting Green Superseam Tool interlocks two sections of putting green turf together for a stronger bond preventing separation and seam rupture. Its unique design allows the Superseam to be seamed over slopes and undulations without it effecting the play of the golf ball.
The New Superseam Putting Green Tool makes the seams to magically disappear!!!
Practice Makes Perfect.
To master the Superseam Tool, it is best to position yourself with one knee on the rear of the tool while placing your hand firmly on the surface. Then use your “Knife Hand” and slide down the tools “S” side as shown in this picture.
The Superseam Tool is designed to connect as many Superseam Tools together by using the Superseam Connector and hardware. You can quickly fasten multiple Superseam Tools together for production and better efficiency.
If you are a beginner or have long seams to conquer with the Superseam Tool, Use a grey metallic sharpie marker and mark the Superseam Tool prior to cutting. This will make your Superseam more efficient and prevent user error.
Minimal Trimming May Be Needed.
Not all Superseam installs are perfect. Trimming may be needed if the Superseam is overlapping. Overlapping may be caused due to elevated slopes or mounds in the underlying grading materials. It is better to trim than it is to have a gap between any seams. Remember the objective is to create an “Undetectable Seam”.
The Superseam tool is not for every seam installation, however, when you are installing synthetic turf that has a 50 ounce face weight or greater, don’t take the chance and regret it later. The Superseam tool is available in 6’ and 4’ lengths and can be ordered with a connector bracket. The connector bracket allows the installer to connect multiple Superseam tools together for more efficient seams.
Now Enjoy the Magic of Superseam…“The Undetectable Seam Integration Tool.”