National Diversified Sales (NDS) is a plastic trench drain manufacturer based out of California. They have a fantastic selection of plastic trench drain systems that are used in residential and commercial applications. The 3 inch-wide Mini Channel is popular because its honeycomb design and inexpensive price appeals to contractors and homeowners. However, a big part of the drainage system’s popularity comes from the number of complementary grating options offered.
The standard grate offered with the Mini Channel is still a 3 foot long plastic grate, which is offered in six colors (gray, white, green, black, red, and sand). Gray was the go-to color in the past, but customers are now branching out for colors that blend with the hardscaping; sand and white plastic grates, especially, are gaining popularity.
For those with a more discriminating taste, NDS offers two slotted brass grating options. The 1 foot long brass grates come in a satin or polished finish. Besides being simple, shiny, and elegant, they contain chamfered holes for optional screw placement, which helps keep the grates secured in the channel.
Another option available for Mini Channel customers is decorative cast iron grates. These aren’t the ordinary slotted grates of yester-year; the cast iron grating product lines below illustrate the beautiful side of a functional product that was previously considered a necessary – and ugly – evil by many homeowners. (Note: these grates are shown with a baked-on oil finish unless otherwise specified but come standard in an unfinished cast iron.)
Currently, five styles of cast iron grates work with NDS’ Mini Channel system: the Acanthus, Interlaken, Carbochon, Locust and the Minnione. There are a few basic differences between these four Mini Channel grates. The Interlaken is an intricate geometrical pattern while the Minnione has a flowing design. The Locust pattern evokes the feel of leaves blowing in the wind. Meanwhile, Carbochon’s open area is only accentuated by its bold pattern.
Style aside, the most noteworthy difference in the grates is length. The Interlaken (11″ long) is an inch shorter than the Minnione and Locust grates (12″ long). The Carbochon (14” long) outdoes all three grates by inches. I think the length of the grates is important because it determines what you can do with the design of the run. Unfortunately, it is often overlooked during the planning stage and leads to extra work later on.
Another difference in the grates is how they fit into the Mini Channel. Take a look at the photo above. Minnione, the thinnest grate, does not rest in the channel with the same depth that Interlaken, Locust and Carbochon do. While the other grates are cast with tongues that fit snugly into the Mini Channel’s patented “flying buttress” lip, one gets the feeling that the Minnione sits on top of the drain rather than resting inside it.
The foundry uses cast iron as the standard material when making these decorative grates but also manufactures cast brass, bronze and aluminum grating for an additional cost. We should note that cast iron grates are uncoated (raw) and will form a rust coating over time. The rusting process, when reproduced artificially to save time, is called a baked-on oil finish. I find the resulting patina charming.
If your application doesn’t support this view, though, consider painting with an epoxy or powder coating. The powder coating process smoothes out the natural texture of the cast iron grates, giving them a softer, less metallic look. You can really feel the difference between the painted and baked-on oil finishes; the process encased these grates in paint rather than changing their outer layers.
Let me just demonstrate the difference between the two available finishes in another way. Look at the Interlaken grates shown below: in terms of color, they are very similar. But, if you look closer you can see the different shine, the thickly coated surface of the grate on the right. It’s been powder coated. The grate on the left, though, has a baked-on oil finish. I’ll leave you to decide which one you like better. For additional information on cast iron grating finishes, visit our “Cast Iron Finishing Options” blog.
Cost is all in a person’s perspective, especially when talking about trench drain products. A simple plastic grate that comes in six basic colors is available for a very low price per foot. NDS’ brass grate, a beautiful, no-hassle solution for those still worried about rust or decor, is the most expensive. The cast iron grates, which add style and variety, come for the more moderate price that falls somewhere in between and have beautiful finish options. They are the true extra mile, the art to efficiency, and are the balance if a cost-efficient and stylish grate is desired.
For cut sheets and literature on the products discussed here, download the available drawings embedded throughout the article. If you’d like a quote on a Mini Channel drain system or decorative cast iron grating, contact Trench Drain Systems (TDS) at 610-638-1221 or send an email.
There are many plastic trench drain manufacturers in the marketplace. By far, the top two manufacturers are Zurn Industries and National Diversified Sales (NDS). Zurn is a world class plumbing supply manufacturer headquartered in Erie, PA. One of the four business grouping Zurn has is Drainage Products. The Perma-Trench products represent the plastic trench drain component of their drainage products offering. NDS is a manufacturer of plastic components used in storm water management, irrigation, water flow control and landscape water and root management. They are headquartered in Woodland Hills, CA.
These two very different companies find an overlapping marketplace with their pre-sloped, high density polyethylene product lines. For NDS, their Dura Slope product line was an outgrowth of their landscape drainage product line development. This product was meant to be a high performing drainage product used in larger landscape and residential projects.
The Zurn Perma-Trench products (all high density polyethylene) were developed as an economical alternative to polymer concrete trench drain for industrial drainage applications. The work horse of the Zurn trench drain product line is their 4” wide channel call Z886. Both Dura Slope and Z886 have similarities in channel composition and drainage capabilities. However, each has strengths which should be considered when choosing a product for a particular application.
Dimensional Comparison – Above is a photo comparing the Zurn Z886 and Dura Slope channel bodies as received from our supplier. At first glance, the main difference you see when comparing two is the length. The Zurn product is 2 meters (80”) in length while Dura Slope is 4 feet (48”). Next, you will notice that the Dura Slope has a black plastic cover attached with locking devices. The Zurn channel has 4 metal “spreading bars” which are used to keep the channel walls from flexing during installation. Dura Slope’s black cover helps to prevent channel compression during concrete placement, but also works to keep channel free from debris during drain installation. As a side benefit, the locking devices come free with the Dura Slope channel.
The channel width, slope and colour are relatively similar between these two products. And likewise, both products can achieve continual slopes of 100 feet (96 in the case of Dura Slope) and have the deepest channel section being 12”. Look at the close up photo comparing the two below.
Flow Data Comparison – The flow data reported on the Zurn product is 20-25% higher than that reported on similar invert depth Dura Slope channels. This didn’t seem reasonable since both channels are so similar. To investigate the disparity, I compared Z886 and Dura Slope channels of similar depth. (See Photo Above)
Flow rate is a function of the cross-sectional area of the channel, the channel slope and the channel material. As the material in each is HDPE, we can ignore this as a factor of the flow difference seen. The cross sectional area of each channel seemed to be similar. Z886 is a full 4” wide with a rounded section at the bottom. Dura Slope has a top width of 4.5”, but, then goes into a taper to the rounded bottom which has a 4” diameter. Maybe, Zurn has slightly more area…maybe. Could the extra 0.05% slope of the Z886 explain the 20% greater flow data? I don’t think so.
Upon closer analysis, I learned that Zurn’s technical data defines the invert depth of a channel to be the distance between the top of the grate and the lowest point in the channel. Dura Slope, on the other hand, measures the invert depth as the distance from the bottom of the grate to the lowest channel point. The resulting 0.75” difference has an effect on the overall cross-sectional area calculation, and in turn, affects the flow calculation. In essence, Zurn measures flow of the channel without a grate while Dura Slope recognizes that you will have a grate in the trench while it is in full flow. When each company’s data is compared after adjusting for this depth difference, Zurn shows only an 8% higher flow rate than Dura Slope.
Channel Feature Comparisons – Other channel features worth noting include built in rebar clips and anchors, built-in bottom outlets, channel connections and end outlets. Both Zurn and Dura Slope products have rebar clips built into the channel body. (See above.) Rebar clips are used to help suspend the channel within an excavated trench during installation. Rebar sections are generally hammered into the ground. The purpose of the rebar clip is to attach the channel to the embedded rebar. The rebar clip designs for the Z886 and Dura Slope channels are different but equally functional. Z886 has a side clipping design while Dura Slope has a clip opening that is perpendicular to the channel. Both clips have tie wire holes. The Z886 wire tie hole is in the outer most side of the clip.
Rebar clips are additionally helpful to stabilize and secure the channel after it has been set in concrete. One complaint I’ve heard about plastic trench drain channels (as opposed to polymer concrete) is that, over time, there is a tendency for the channels to separate from the hardened concrete, leaving a gap that can fill with debris and pinching the channel opening. In comparison to polymer concrete channels, this is probably a true statement, though maybe a little misleading. To help secure the channel firmly into the concrete and minimize this separation, Zurn has designed additional anchor posts at each rib point of the channel. Dura Slope doesn’t have additional anchors at their rib points. However, the HDPE used to make the Dura Slope product seems to be more rigid, maybe because of added fillers used in the plastic.
A feature of every Dura Slope channel is a built-in bottom outlet. This gives the contractor flexibility in deciding the drainage points of a long run or the convenience of not having to order a separate adapter if a bottom outlet is required. To use the bottom outlet, a 4” diameter hole bit is used to drill out an opening in the channel within the bottom outlet. Thereafter, a 4” schedule 40 pipe hub or Sch. 40 hub insert (DS-126) can be attached.
Zurn’s Z886 bottom outlet design also gives you a degree of flexibility. The Z886 doesn’t have a built-in bottom outlet with each channel. However, separate bottom outlets are available in 2”, 3”, 4” and 6” diameters. These can be installed anywhere along the channel bottom which allow for more complex drainage configurations.
Both Z886 and Dura Slope have tongue and groove joint connections. They allow for quick and easy installation. Dura Slope has a trademarked DuraLoc TM design which snaps to lock the channels together once the tongue has been properly inserted into the groove. I am impressed to see how quickly these go together and how straight the channels remain after connection.
The Zurn tongue and groove joint connection slides together easy enough. But, it just isn’t as user-friendly as the Dura Slope product. To secure the joints into place, you are required to place a screw at each side of the joint so you can mechanically connect the channels.
One of the selling points for the Z886 channel in Zurn literature is the fast installation times due to the tongue and groove connection and the 80” channel lengths. The longer channel lengths are thought to reduce the hassle of connecting channel (which is what takes time in setting drain). When compared to traditional polymer concrete systems, this may be true.
However, you cannot make the same inference when comparing Dura Slope and Z886. I feel the quick locking channel design feature of Dura Slope overshadows any installation advantage that the Z886 product may have despite the longer channel size. Dura Slope is just easier and quicker to assemble.
While I’m on the soap box commenting about channel length, I want to point out that long channel lengths are best when you have larger, longer channel runs. For smaller projects, you may not have need for a full 80” section. For common trench drain applications, such as a 12 ft or 16 ft wide driveway drain, a channel with a 4 foot length would be optimal. If an 80” channel was to be used on this project, a portion of the channel would have to be cut and discarded. As the project becomes larger in scope, a certain amount of flexibility is inherited. Lengths can be changed easier in the field to accommodate the channel increment. And with larger projects, if a channel is to be cut and discarded, it is a much smaller percent of the project cost than it would be in a small residential project. This is not to infer that smaller length channels shouldn’t be used in larger drainage projects. Smaller channels can be quicker to install, and they are easier to store.
One feature that aids Z886 in large drainage projects is its extender panels. These are wall panels that can be added to a channel to allow the drain to be installed at greater depths or with longer continual sloping runs. Dura Slope doesn’t offer this feature.
A final feature to compare between these two systems are end caps or end outlets. Both products have caps and outlets made from HDPE, which makes it easy to trim and drill out in the field using standard power tools. Both have a design that allows the outlet to attach by inserting into a channel groove and the end cap (shallow end) to be attached with screws. Zurn’s outlets are supplied with screws, while Dura Slope requires you to purchase these separately. There will be an excess portion of the cap which needs to be removed, with both systems, to make the cap level with grade. Dura Slope end cap design shows a depth scale that corresponds with the channel you are using as the last channel to make trimming easier. Zurn’s end cap design has a saddle that rests within the channel to make screw mounting easier during installation.
To recap, below is a quick comparison of the Z886 and Dura Slope with respect to channel features and geometry.
Parting Comments – If we are to look solely at the merits of each channel, I would say that Dura Slope has more to offer both home owners and contractors. The Dura Slope was designed to be easy to handle, quicker to install, with minimal assembly required. I personally like the shorter channel lengths because they fit on my shelves and are much easier to ship to my customers. I feel the plastic used to make the Dura Slope is stiffer than that used in Z886, which leads to straighter channel installations and less channel-concrete separation.
Having said that, I acknowledge that the Z886 channel has advantages over Dura Slope in applications where long, continuous slopes are required. By using extender panels, runs as long as 300 feet of continual sloping drain are achievable. In addition, Z886 has a wider variety of outlet diameter options which can help in more complex drainage projects. This is one of the reasons why you will see Zurn Z886 specified on big jobs more often than you will see Dura Slope.
The channel component of any trench drain is important when considering the engineering properties and installation. But this is just half of trench drain. The portion of the drain that people see after installation is the grate. Increasingly, the channel grating is becoming the focal point of the trench drain selection process. Aesthetics, ADA compliance, load capability and corrosion resistance are all properties to consider when selecting a trench drain grate. Part 2 of this report will continue the discussion on Zurn’s Z886 and NDS Dura Slope by focusing on trench drain grate options available from each.
Trench Drain Systems is a company which specializes in providing quick solutions to drainage problems. For more information about the trench drain products discussed in this article, visit the website or call 610-638-1221 for immediate assistance.
The Z880 Perma Trench is one of Zurn’s most popular residential trench drain product lines. Its name may sound intimidating, but there’s nothing to fear from this plastic drain. It was designed for pools, patios and landscape drainage much like its competitor, the NDS Mini Channel. Both the NDS Mini Channel and the Z880 are 3” wide at the top, and both systems have similar features that give each other a run for the money.
Channel Body Differences
The difference between the two systems really starts with the channel bodies. Take a look at the photo above.
The Mini Channel (shown left) has a gray, honeycombed channel design meant to distribute load stress and prevent the system from collapsing. This design extends to the grate supports, which hang out from the channel walls in an upside down flying buttress.
You can see that the Zurn Z880 (shown right) has a thicker, solid channel body. It is composed of high density polyethylene (HDPE), the same material as the Zurn Z886 or NDS Dura Slope commercial-grade trench drain systems. The inherent durability of the channel body gives some “street cred” to this little patio drain.
The Z880 channel body also has “ribs” extending from the outer walls that give the channel extra surface area at vital contact points to the surrounding concrete. The ribs help “grab” the concrete, anchoring the system in place and providing additional strength. The channel will not separate from the concrete once installed. The ribs also add flexibility to the design of the system because they serve as cutoff points in the drain that can still connect to other modular channels or outlets. I’d estimate the cutoffs are every foot.
The walls of the Mini Channel are made of smooth PVC. The absence of ribbing is advantageous when installing in a paver patio but poses a problem in the long run if you want to install it in concrete. Without ribbing to act as anchoring points, the drain body can begin to separate from the concrete years after installation. In addition, water and dirt may begin to flow between the concrete-channel interface, causing the channel to pinch. To prevent this pinching effect and the subsequent weakening of the channel wall, make certain that the Mini channel grates are always securely fastened down.
Grating Option Comparison
While Mini Channel grates come in a standard slotted pattern, the Z880 grates (shown below) have a more decorative pattern that gives them a classier appearance. The thicker grate also holds more weight, providing more structural integrity than thinner Mini Channel grates, but ultimately has less open area for water to drain.
The Z880 and Mini Channel systems each offer six color options which are the same with one exception. The Z880 offers a sky blue grate while the Mini Channel offers a forest green grate.
If you choose the Z880 system, you’ll be surprised to see that the channel matches the grates’ color. Unlike pool drains by other suppliers, the Zurn Z880 eliminates this “edge line of a different color” that borders the grating. This gives the system an overall nicer appearance.
Grates for the Z880 system clip into place. Each grate has several “tongues” on its sides that snap into the channel grooves. It’s easier than buying grate screws and lock downs, won’t create weak points in the channel structure and can be popped out of place easier for cleaning.
Iron Age Grating Options – Cast iron decorative grating is available for both drainage systems. Created by Iron Age Designs, the grates are both beautiful and efficient.
The Mini Channel has four decorative patterns that fit the system, three of which are shown below: Minnione, Carbochon and Interlaken. Each grate is slightly different in terms of thickness and how it sits inside the channel. Iron Age cast iron grates make NO accommodations for screws needed to lock down the grate.
So far there is only one cast iron grate option offered by Iron Age for the Zurn Z880 pool drain. What amazes me about the pattern is that it’s a Regular Joe. No, really, it is. I’ve never found out who was behind it, but somewhere along the lines the decorative option for the Z880 drain became a cast iron slotted grate. Of course, it looks entirely more sophisticated than a standard slotted grate, but it’s something I’ve never stopped being amused about.
One thing that is not amusing about the Regular Joe grate for the Z880 is the placement of its “tongues.” In the picture above, you can see the inconsistency between the plastic Zurn grate and the Iron Age Designs option. The lockdown tongue on the cast iron grate is placed too high, which means it probably won’t secure into the channel properly.
I don’t want to sell the Z880 drain short, though. Zurn does offer four other decorative options, including a bronze decorative grate, for homeowners who want to upgrade from plastic without buying the Iron Age grate.
Whereas, the Mini channel may wear and tear more quickly (especially in regions of freeze-thaw) because of the cellular channel design, the Z880’s solid body design and anchoring points makes it a more rugged product over the long haul. The Mini Channel is a sleeker, less expensive channel drain system that works well when used with pavers. The Z880 is a sturdier system designed for concrete installation. These two systems are so similar, yet they are worlds apart.
Every so often an ADP (American Drainage Products) plastic grate is mistaken for NDS Spee-D Channel. There is a good reason for that. ADP was a company based out of Columbus, Ohio who carried a product line that overlapped with those offered by NDS (National Diversified Sales). In 1997, NDS purchased ADP and incorporated their product line into the NDS offering. The redundant products have been supported by NDS over the years but are being phased out. That is the case for the ADP 2” and 4” channel drains. Replacement components, such as plastic grates, and some channels are still sold by NDS, though they are difficult to locate.
ADP 2” Channel Grate – As first glance, the 2” ADP grate can be mistaken for an NDS channel grate because it is made in the same style as the NDS Mini Channel. The thin, slotted plastic grates come in an assortment of colors (shown below). The slots have a center rib running down the length of the grate, which makes it more structurally sound and gives it the “double slotted” look.
Distinguishing features between the two grates can be seen in the photos shown below. While the Mini Channel grate (left) is 2.75” wide and 36” long, the ADP Channel grate (right) is 2” wide and only 24” in length. Another subtle difference between the two can be seen in the screw hole locations. The longer Mini channel grate only has four locations screw holes used to attach the grate to the channel while the 2” ADP grate has six screw holes.
Grates are not the only replacement component available for the 2” channel system. End caps, channel couplers and channel supports can also be purchased for this system. Channels are available in 4 foot lengths but are not being advertized because NDS is trying to phase out this product line. If you like this product, you’d better hurry before it is gone forever.
ADP 4” Channel Grate – For the longest time, I incorrectly thought that the ADP 4” channel was a Spee-D Channel system. The two products are so similar, it can fool you. I was first introduced to the ADP 4” channel when I was replacing a trench drain in a customer’s driveway. The 4” channel drain had been installed in the drive without the proper support by the previous contractor and failed under use. When I removed the channel, I recall thinking that this must have been an older version of Spee-D channel because it had a few style differences yet still looked identical to the Spee-D Channel.
Many similarities exist between the Spee-D and ADP 4” systems. Channels are extruded gray PVC plastic and supplied in 10 foot lengths. The 4” wide grates are 24” long and are slotted with a similar slot design. But upon closer evaluation, the Spee-D grate (left) is about 1/8” narrower than the ADP 4” grate. In addition, the ADP grate (right) has slots with squared corners and screw holes that are directly opposite of each other.
Many more differences are apparent when you compare the bottom side of these grates. The Spee-D grate has a thicker, shorter rib section which defines the slot. The ADP 4” grate has thin, deeply protruding rib sections. These thin ribs, while making the grate more rigid, may also make the grate more brittle and easier to crack during aging. Another difference between these two grates can be seen in the lips that fit into the channel: the Spee-D grate has an elongated edging while the ADP product has a V-notch.
There are other grate options for the ADP 4” wide grate. One really interesting option is the flanged grating (shown on the top in the photo above). The purpose of the flange was to cover up or mask the plastic channel edging so there would not be a color mismatch in the trench drain after installation. I suspect, however, that the edging tended to fatigue and break under use. Maybe this is why NDS hasn’t used this idea in their existing product lines.
The ADP 4” grates of both styles are available in four colors: black, sand, green and gray. The flanged 4” wide grate is also available in the color “brick”. End caps, outlets, couplers and channel supports are also available for this system. While NDS no longer advertises these channels, they are available (for now).
The size, shape and material used to make a catch basin vary based on its intended application. Round plastic catch basins are smaller and usually found in residential applications while larger, cement basins are used for heavier duty projects. Many residential basins – even those on the larger side of the scale – feature optional decorative grating to make a potentially ugly drainage product look more appealing and less intrusive.
Over time, our sister blog has written several useful articles on the applications, sizes, installation methods and features of catch basins. They are listed with excerpts below:
“A driveway that slopes into a garage can direct storm water toward the house. Trench drain can be used to remedy this drainage problem by helping to redirect water away from the garage or living space. However, a big contributor to the water problem can also be downspout water. Driveways often have downspouts that drain roof water directly onto the pavement. If the driveway doesn’t slope away from the house or allow for adequate drainage, water pooling or flooding can occur. This article is about how simple catch basins can help to re-route downspout water…”
“There are a number of options available for landscape contractors and homeowners who need a large catch basin. By large, I am referring to a basin with a maximum size of 2’ x 2’. A catch basin of this size (2’ x 2’) is at the boundary that separates commercial products from residential products. Basins larger than 2’ x 2’ are generally made with the intention of being exposed to heavy traffic. This article will be discussing some of the “large” catch basin products available for residential application…”
“I like to think of a catch basin as the “first line of defense” in cleaning up rain water and drainage pipes. It is common for homeowners to put their downspout water into a pipe that then travels out to the street or a back yard location. This often leads to clogged drainage pipes. Over time, leaves, sticks and sand particulate from roofing shingles will build up in the pipe to gradually reduce drainage efficiency. A catch basin helps to reduce this problem in two ways. First, the grating that covers the basin filters out the coarse debris that finds its way through the downspout, thus “catching” the biggest contributing factor to clogged drain pipes…”
To purchase any of the catch basins in these blogs, visit our online store or contact Trench Drain Systems at 610-638-1221.
Recently, a number of people contacted us regarding the NDS 8 inch Pro Series Channel Drain. In a previous article, the 8” Pro Series was mentioned, though not in any great detail. In this article, I’ll elaborate on the channel and grating features this popular channel drain system.
The Pro Series by NDS
The Pro Series is a family of plastic channel drain products manufactured by National Diversified Sales (NDS) under licensing agreement from First Plast S.R.L. (Italy). There is a similar product line in Brazil made by Tigre Plastics that may be licensed under an agreement with First Plast, as well.
These injection molded channels are made with PVC containing ultra violet light inhibitors to help prevent fading and cracking. Pro Series channels are neutral (non-sloping), reinforced with ribbing every 4 inches and come in widths of 3”, 5” 8” and 12”. Options on grating, channel length, corner sections and outlets differ between the various width products.
However, each Pro Series channel features a unique, interlocking end joint connection. The reinforcement ribbing doubles as a cutting point (in the event that the channel needs to be shorted) which maintains the interlocking end joint connection. These features help make the Pro Series product line a smart, affordably drainage system for residential applications.
8” Pro Series Channel Details
The 8” Pro Series channel is used in applications where rain water accumulates rapidly or in applications requiring a larger runoff reservoir than is offered by the smaller Pro Series products. Technically speaking, the 8” Pro Series is named for its width, which is actually 7.875 inches wide. The channel width, or throat, is about 6 inches wide. All channel lengths are ½ meter (20 inches) and are available in shallow or deep profiles (shown below).
The 8” shallow channel is about 4 ½ inches from the top of the grate to the bottom of the channel. Each shallow channel will hold 2 gallons under static conditions (no flow). The 8” deep profile channel, in comparison, is 7 ¼ inches in height and will hold 3.5 gallons under no-flow conditions. The amount of runoff water that these drains will effectively handle depends on the length of the drain, the diameter of the pipe used to drain the system, the pitch of the channel and the size of the openings in the grate used with the system. NDS has technical data that can be used to design a trench drain system capable of withstanding rainfalls typical to your geographic location.
8” Pro Series Outlet Options
Both the shallow and deep profile channels have end caps that can double as a 3” or 4” sewer and drain pipe connections. (See Below) These end caps have knock out sections of plastic that enable water to flow out or in. The shallow profile channel has an additional fitting that allows 3” or 4” S&D pipe to be attached to the drain from the side or the bottom of the channel. The deep profile channel doesn’t have this option. Again, there are knock out plastic sections that cover each of the pipe attachments on this special outlet.
8” Pro Series Grating Options
NDS sells 4 grating options for the 8″ Pro Series. Each grate is 7 ¾ inches wide, 19 5/8 inches long and ¾ inches deep. You will need to have one grate for every section of channel, as they are the same length. Each grate is connected to the channel by 4 stainless steel screws (sold separately).
Two of the most common 8” Pro Series grates are shown below. The top grate in this photo is a pedestrian rated perforated grate (Part No. 836) which is ADA compliant and can drain 15.33 GPM per linear foot of grating. The bottom grate is the standard light traffic slotted grate (Part No. 837) that has over twice the draining capability of the perforated grate. Both grates are made of high impact Polyolefin and are light gray in color. Not shown in this photo is a glass reinforced nylon slotted grate (Part No. 838), which is said to be able to withstand heavy truck traffic while also being ADA compliant.
Two cast iron grates are available for the 8” Pro Series. These are shown below. The black slotted grate (Part No. 888) is made by NDS, has 54 GPM drainage capability per linear foot of grating and is able to withstand truck traffic. The decorative grate beneath the slotted grate is called the 8” Carbochon and is made by Iron Age Designs. This grate was specifically designed to fit the 8” Pro Series channel, is made of ductile iron, is ADA compliant and has a higher open surface area per foot than any of the NDS grating options.
The Carbochon grate isn’t supplied with bolt-down holes or a protective coating to prevent rust. However, the aesthetics and pricing of this Ironage product make it an attractive option to the standard slotted cast iron grate. The Carbochon grates are available from Trench Drain Systems and can be purchased with an oil-baked finish or a custom epoxy coating.
Pro Series Installation Features
The Pro Series channels have three useful installation features that are common to all available sizes. These are illustrated in the photo below.
Pro Series channels have a unique interlocking channel design that is the key to their modular system success. This “tongue and groove” design allows each channel to securely lock to the adjoining piece. The “male” end of the channel easily slides into the “female” side of the adjoining channel when adding length to the drain. This connection joint can be made stronger by using PVC cement at the contacts prior to locking the channel together.
Another key feature that makes the Pro Series a unique modular system is the reinforcing ribs. Not only do the ribs give the channel walls rigidity, they are designed to be a cutting point for channel shortening while still keeping the “male” end of the channel that is necessary for attachment. No other trench drain system on the market has this feature.
Each channel also has “feet” that can be used as a rebar attachment site during installation. Generally, rebar is hammered into the ground at the foot locations. Wire is then wrapped securely around the rebar and channel foot. Final adjustment can be made to the channel to ensure the top of the drain is set to the desired elevation prior to pouring concrete. Instead of rebar, wood stakes can be used. In this case, wood screws can be used to firmly attach the channel foot to the installation stake.
In summary, the NDS 8″ Pro Series is a high volume channel drain for residential applications. The wider channels help insure that water is quickly removed from hardscapes. The unique design of the Pro Series facilitates ease and speed of installation. Grating options are comparatively meager, but growing due to the new selections becoming available by Iron Age Designs. For questions regarding this product line, contact the folks at Trench Drain Systems at 610-638-1221.
Last entry discussed differences and commonality between extruded channel drains manufactured by NDS and Stegmeier. I wanted to continue along this path and discuss two other very similar extruded products — NDS’s Spee-D Channel and Stegmeier’s Flowmaster. The Flowmaster is marketed as a professional grade channel drain for swimming pool decks. The Spee-D Channel is sold as a general purpose drain for residential applications that include driveways, paver patios and pool decks. Let’s first look at the two products side by side. NDS Spee-D Channel is to the left while Stegmeier’s Flowmaster is to the right. Both channel drains have a similar cross section and have similar geometry. Both are about 5 inches wide and 3 inches deep. Both products are made from extruded PVC.
Two things stand out in the photo above. First, the wall thickness of the plastic is greater in the Stegmeier product. They also have a smaller amount of open air space than does the NDS product. This makes the Flowmaster channel much sturdier than the Spee-D channel. You can feel the difference when you hold the product. Normally, I don’t like to recommend extruded channel drains in regions that see frigid temperatures because of my concern for cracking during freezing and thawing. I think the Spee-D channel is susceptible to rapid deterioration in this environment. The Flowmaster channel drain stands a much better chance of holding up in colder regions because of the more rugged wall design.
The second apparent difference between these two products is the design of the grate rails. The Stegmeier product has a curved rail that requires a specially designed grate. The NDS product has a straight rail. This may not be much of a difference. But, I think the NDS design makes grate replacement and removal easier. Their design also lends itself to easy adaptation by other grate manufacturers.
Let’s look at some of the grating options of the two products. Below you see the Flowmaster with an aluminum slotted grate. It snaps into place wonderfully. You can buy this in three colors (silver, tan and white). This grate also comes in plastic (again three colors). However, if you wanted to use this product for anything other than a pool or deck application, you would have a difficult time with the grate. I feel the grate would compress or crush a little under car tire applications, for instance. Maybe I am trying to “over apply” this product.
On the other hand, The NDS Spee-D channel has a variety of structural foam grating that is capable of small automotive traffic. If you want ornamental cast iron grating, it is available from Iron Age Designs. Maybe, the Spee-D channel doesn’t look as good as the Flowmaster in a pool deck application, but it has a broader residential appeal due to the grating options.
Another difference between these two products is in the way they couple. The photo below shows NDS (left) and its well-engineered channel coupler versus Stegmeier’s simple design internal coupler. I don’t know which is best. I think the Stegmeier coupler is simple and gives a sturdier connection. I think the NDS system is neat looking, though. And my gut feeling is that the Stegmeier coupler will allow water to seep into the wall cells easier than the NDS coupler. It’s just my gut feeling folks!!
I guess the last thing to talk about is pricing and availability. List prices of both channels are comparable. However, the popular home improvement stores usually carry the Spee-D channel at well below list pricing. Grating is where the pricing differences will be felt. The
Flowmaster grates are generally more expensive than the “off the shelf” Spee-D channel grate. However, you will most likely have to special order any Spee-D channel grate if you don’t want gray plastic. Cast Iron grates for Spee-D channel can be ordered online in raw iron or with a Baked-on oil Finish. The Stegmeier channel products are sold in pool supply stores and by special order. Their distribution network is not as well developed as NDS. If you like the Flowmaster product line, and can’t find a dealer, you can purchase this product over the internet.
Last month, I wrote an article about a plastic channel drain product marketed by NDS under the “Pro Series” brand. This neutral channel product line is manufactured by injection molding. While injection molding is great for making intricate shapes, manufacturing costs associated with injection molding drive product costs up.
There are design and mold costs associated with all formed plastic products. However, extrusion, as a plastic manufacturing method, is well suited for high volume, simple shape production. Being a continuous method, the extrusion process is continuously producing products (more units per hour) and drives down unit of the finished part.
Designed in the cross-section shape of the final product, extrusion dies are less complicated and less expensive to make. When hot plastic is passed through the die in the actual extrusion process, a continuous stream of product is made. Plastic PVC pipe in manufactured by this process.
In the case of plastic channel drain, this “stream” of molded plastic comes out looking like a plastic roof gutter (see photo below).
This article will address extruded plastic channel drains. In part 1, I will discuss common features in pool deck drains manufactured by NDS and Stegmeier. I also discuss the NDS Mini Channel product.
NDS Micro Series vs. Stegmeier Deck Drains
The NDS Micro and Stegmeier deck drains are narrow channel drains designed specifically for swimming pool decks. Generally speaking, these extruded PVC channels are 1.5” wide and 3.25“deep. The channels are used to form a perimeter around a swimming pool to create a drain for incidental pool water. All the products are designed to be installed in concrete. However, channel anchoring techniques during installation differ between the two brands.
Below you can see the NDS Micro Channel (left) compared to Stegmeier’s standard deck drain. Both products are extruded “box” channels. Later, slots are cut into the top surface to form the drain holes. NDS seems to use a small mill to form this slot while Stegmeier appears to use a carbide saw blade. The NDS Micro is actually more narrow (1.25”) than the Stegmeier products (1.625”). The Stegmeier product also has a more rigid feel to it.
NDS offers its Micro Channel pool deck drain in three different colors. That’s it. Stegmeier’s deck drains come in 4 colors and 4 styles. Two of the styles are like the above “box” channel with the integral drain grate. However, they have two other products that have an awesome “press fit” grate that make channel clean out very easy. Stegmeier’s Frontier Deck Drain has plastic “press fit” grates that come in 4 colors. Stegmeier’s Treadmaster Deck Drain has an aluminum grate for the more commercial swimming pool look. These grates come in tan, white and silver. I’m sorry I don’t have photos of these now. In the interim, check out their website www.stegmeier.com.
NDS Mini Channel – The next “size up” in extruded plastic channels is the NDS Mini Channel. This is a unique product that is both economical and sturdy enough to be used in light traffic areas. The 3” wide and 3” deep channel allows for larger water flow than deck drain while giving the home owner a greater selection of grating options. As with deck drains, the Mini channels are connected with couplings and are available with a broad selection of special junction sections.
The highlight of the Mini Channel system is with the grating options. You can select from six colors of plastic slotted “light traffic” grates. These come in 3 foot lengths and can be screwed into place. NDS also offers decorative plastic grates in two patterns and six color options.
If you want a more durable or ornamental product, you can have a slotted brass or cast iron grate. The brass grates are available in polished or brushed finishes and come in one foot lengths. The cast iron grate is available in four patterns (Minione, Interlaken, Carbochon, Locust).
NDS offers a line of channel drain systems called the “Pro Series”. These channels are injected, molded from polyvinyl chloride, and have a neutral slope (no slope). They come in a variety of widths (3”, 5”, 8” and 12”). According to NDS literature asterisk notes, this product is technology licensed from the Italian trench drain manufacturer First Corp.
This product line really has many options if you don’t want pre-sloped channels. From a manufacturing point of view, it makes sense. NDS production facilities would need to stock a bunch of injection mold dies of varying depth in order to make pre-sloped channel systems Injection mold dies are expensive!
With the Pro Series, NDS instead opted to make four channel widths to account for different flow situations. Three of the widest products have two depths (shallow and deep channels). So, in effect, there are seven different channel options in the Pro Series.
The photo above shows three of the four width options (I didn’t show the 12” wide option). The 3” and 5” wide channels come in 40 inch lengths (1 meter). The 8” and 12” wide channels come in 20 inch lengths (1/2 meter).
Pro Series Channels Mean a Flexible Layout
A key feature of the Pro Series trench drain product line is the ability to cut the channels to any desired size. The channels come with a “double ridged” cut line every four inches (4”) along the length of the channel. This makes it possible to trim, for instance, 8 or 12 inches from the channel in order to custom fit the drain into a tight area.
Trim the channel using a simple hand saw. By making your cut in the slot formed by the double ridges, you can easily change the length of the drain while retaining an edge that allows all the standard hardware (end caps and other channels) to be attached . There is no patching of the channel in a custom length situation.
While you can cut a channel to a specific length, specialty channels are available for making 45 and 90 degree bends in the drain.Side outlets are available in 5” and 8” wide channels. Another notable feature is that every channel has a bottom knockout. This gives you flexibility when it comes time to place a bottom discharge. You can place a bottom outlet wherever you want.
Pro Series Grates: Know Your Options
Grating options are not extensive with this brand and vary by channel size. For instance, the 3” wide Pro Series channel only has a gray plastic grate suitable for pedestrian or light vehicle traffic. This may be adequate for home owners that are looking for a budget driveway drain.
The 5” wide Pro Series drain, however, has the most grating options. Plastic slotted grates (class B loading) are available in six (6) colors. Perforated plastic grating is available, but only in gray. A cast iron grate and a high impact resistant plastic slotted grate are also available in 5” width.
The 8” and 12” wide Pro Series products have fewer grating options. With the 8” wide channels, you have a choice of three plastic grates, one of which is perforated, and one slotted cast iron grate. The 12” wide channel only has a plastic slotted grate (light vehicle traffic) and a cast iron grate for heavy traffic. All grates, no matter the width, come in 20 inch lengths.
One thing I like about the Pro Series product line over other NDS brands (such as the Mini or Spee-D series) is that it offers more durability and life to your drain system because of the grate to channel width relationship. I feel it is important to have your grate wider than the channel of the trench. This is particularly important in plastic trench drain products. If the grate is wider than the channel, then the concrete that surrounds the trench will be giving added strength to the channel. Systems that don’t have this added support have to rely solely on the strength of the plastic channel. In this later case, if the ledge that supports the grate breaks, the load capabilities of the grate fail. More on this when I cover other NDS channel drains.
List prices of the NDS Pro Series cover a broad spectrum. The least expensive is, of course, the 3” wide system and prices go up as do the channel widths. Grates with higher load capabilities also come at a premium.
Disclaimer: I am not an organic chemist or a plastics engineer. I’m gathering this information from other sources and I may not be explaining it as accurately as I need to.
Polyolefin — is a polymer produced from a simple olefin, or alkene as a monomer. For example, polyethylene is a polyolefin produced by “polymerizing” the olefin “ethylene”. Another common polyolefin is polypropylene. I consider polyolefin a general term for a family of plastics. (http://en.wikipedia.org/wiki/polyolefin)
Polyethylene — is a semi-crystalline plastic with excellent chemical resistance, good fatigue, and wear resistance. They can have a wide range of properties which are determined by the length and degree of branching of their polymer chain. In general, polyethylenes have good resistance to organic solvents, high impact strength, are light weight, resistant to staining, and have a low moisture absorption rate. They are easy to distinguish from other plastics because they float in water. (http://en.wikipedia.org/wiki/polyethylene)
HDPE (High Density Polyethylene) — HDPE is the most common polyethylene used in industry. It offers excellent impact resistance and high tensile strength. Technically speaking, it has a low degree of branching and thus a stronger intermolecular forces. HDPE is non-toxic and meets FDA and USDA certifications for food processing. It is commonly used for the manufacturing of milk jugs, margarine tubs, detergent containers and trash cans. It is also an excellent material for use in trench drain and storm sewer pipe.
Polypropylene is an economical material that offers a combination of outstanding physical, chemical, mechanical, thermal and electrical properties not found in any other thermoplastic. It has a lower impact strength that does HDPE, but it also has better tensile strength and superior heat resistance.
Structural Foam — is a structure imparted to an olefin during processing that gives the plastic addition strength and resilience. More on this later.
PVC (Polyvinyl Chloride) — Is a widely used thermoplastic polymer. Over 50% of the PVC products manufactured are used in construction as a building material. PVC offers excellent corrosion and weather resistance and has a high strength-to-weight ratio. PVC is inexpensive, easy to clean, and a popular replacement for wood and concrete building materials. It is used in house sidings, drainage pipe, window profiles and plumbing fixtures (such as some trench drain). Despite appearing to be an ideal building material, concerns have been raised about the costs of PVC to the natural environment and human health. (http://en.wikipedia.org/wiki/polyvinyl_chloride)
Fiberglass Reinforced Polyester — Polyester is a category of condensation polymers which contain the ester functional group in their main chain. This group also includes polycarbonates. Polyesters are popular for being used as a woven fabric. When fiberglass is added to polyester, the resultant material is more durable and resistant to impact.
UV Inhibitors — These are chemical additives that are added to plastic which help to retard the damaging effects of ultraviolet light to the plastic.
Injection Molding — This is a forming method by which intricate trench drain products (or other plastic shapes) can be shaped. In this process, a heated and liquid thermoplastic is injected into a mold that contains a cavity that has the shape which is desired. Once injected with plastic, the mold and part is cooled. The resulting plastic shape is removed from the mold and trimmed of flashing (excess plastic). This method is needed to form pre-sloped trench channels. Though mold costs are expensive, one mold is required for each size of pre-sloped channel.
Extrusion — Another method of making trench channel is extrusion. In this process, a heated batch of thermoplastic is continuously injected through a water-cooled die. The shape of the die will determine the cross-section of the extruded part. This method can be used to make simple, non-complex parts such as pipe, tubes and u-shaped channels. The most inexpensive channel drain products are made using this forming method.