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.