National Diversified Systems (NDS), a plastic trench drain manufacturer based in California, has a dazzling display of trench drain systems that appeal to homeowners and contractors alike. This 3 inch wide channel system comes in 6 foot long, easy to install sections. This product is popular because of its simple construction and inexpensive price. However, a large portion of its allure also comes from the variety of grating styles it has available.

The most common grate for the Mini Channel is the standard 3 foot long gray plastic grate (shown on the right). NDS also offers a plastic grate in 5 other colors (white, green, black, red, and sand). For those with a more discriminating taste, NDS offers two simple brass options (shown on the left). The one foot long brass grates are slotted and come in a satin or polished finish. Besides being simple, shiny, and elegant, they contain chamfered holes for optional screw placement which help to keep them fastened to the channel.

Decorative, cast iron products have recently become available for Mini Channel customers.  The cast iron grating product lines offer a beautiful side to what may otherwise be only functional. Currently, three styles of cast iron grates work with NDS’ Mini Channel: the Interlaken, Carbochon and the Minione. These products are not ordinary slotted grates. The Interlaken is an intricate geometrical pattern while the Minione has a flowing design.  Meanwhile, the Carbochon has a bold presence that only accentuates its open area.

 There are a few basic differences between the three Mini Channel grates. Style aside, the grate’s channel fit is the next most noteworthy difference. A comparison of the three grates illustrates this difference.

 The Minione is a thinner grate than the Interlaken. It does not rest in the channel with the same depth that Interlaken and Carbochon do. One gets the feeling that the Minione sits on top of the drain, rather than in it.

This could mean that the Minione grate is more susceptible to become dislodged than the other. The Minione grate is designed with two dimples that are the locations for optional screw holes (they do not come pre-drilled). If used with screws, the Minnione becomes as reliable as any other grate in its class. Another small difference between the grates is the length. The Interlaken (11″ long) is about an inch shorter than the Minione (12″ long), and the Carbochon (14” long) outdoes both grates by inches.

Cast iron is the standard material used to make these decorative grates. Cast brass, bronze and aluminum products can be manufactured for an additional cost. We should note that cast iron grates are uncoated and will form a rust coating. In some cases, the rusted look can be endearing.

If your situation doesn’t support this view, though, consider painting with an epoxy or powder coating.  I had two samples of the Mini Channel grating painted because I was curious to see exactly how the process would affect the grates’ performance and appearance over time.

The results, if I may say, are charming.  The powder coating process smoothed 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.  One particularly interesting fact to note:  the grates shown to the left have been painted neutral colors – black and dark brown, but with a purchase over 60 LF a wide variety of colors can be chosen from.  Wowzer!

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.

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.

Previously in this blog, I documented the assembly of a small run of trench drain that was to be used in a garage that was being built. This current article will address the installation of trench drain in an existing driveway. Most homeowners that purchase trench drain are looking to resolve an existing drainage problem. From my observation, driveway drainage problems are the most common. The problem can vary from being merely a low spot in the drive that causes the pooling of water to the unfortunate deluge of water that enters the garage each time there is a heavy rain.

In this situation, the homeowner was getting water into his garage with every hard rain. Further investigation suggested that water was running through a seam at the asphalt-garage floor interface and filtering to the foundation which caused dampness at the base of his basement walls and an over active sump pump. In addition to having a driveway that gently sloped toward the house, his house was at the low end of the street, which made his site more prone to collecting street run-off. To make matters worse, he had downspouts from the roof on either side of the garage door that supplied more water to the affected area.

To remedy his problem, it was decided that a trench drain be installed abutting his garage floor to accept the water from his downspouts. The water was to be discharged toward his back yard, which sloped to a creek. The home owner selected a pre-sloped 4″ wide polymer concrete trench drain (Polycast 600) with cast iron grates and steel channel protectors. The drain channels of this system were pre-sloped (not neutral) so water would flow the moment it entered the drain.

The Installation

Prior to any work, a sheet of plastic was hung to protect the garage door and siding from slurry and concrete splashes. A cut line was made in the asphalt 20 inches in front of the garage door using a concrete saw. The diamond blade on this saw had a 6″ cutting depth which made it able to cut through the 4 inches of asphalt and another 2 inches of the gravel below. This asphalt strip was then cut into smaller squares for easy handling during removal.

The sectioned asphalt and underlying gravel was removed manually. In this case, gravel and asphalt was put into the back of a pick-up truck and taken to a land fill for disposal. During this time, the downspouts were fitted with the 4″ PVC fittings necessary to divert the roof water into the trench and drainage pipe.

To assemble the channels, placement began at the lowest point (invert out) and progressed to the shallowest end. A level line was established just below the surface of the asphalt and 14″ from the edge of the garage floor. Installation hardware was attached to the first polymer channel section (4 foot length). The channel was then set in place, suspended 4 inches above the excavated surface, with the use of #4 rebar.

The top edge of the channel was adjusted to meet the level line. Vertical adjustments were done by sliding the installation chair on the rebar. Horizontal alignments were made with the adjusting bolts on the installation chair. Installation hardware was added to the end of the second channel and attached in an “end to end” manner with the first channel. Again, the second channel was suspended 4″ above the excavated surface and adjusted laterally and horizontally on the rebar supports to match the level line. This technique was repeated until the last channel section was put in place.

Once the channel was assembled, end caps (with knockouts) were installed, down spouts and piping was attached and grates were put in place. The grates were wrapped in plastic sheeting to protect them from concrete, as well as to help keep concrete out of the trench. Some people place a strip of plywood in the grate recess during concrete pouring. This is a good idea. It allows you to keep the grates clean and the trench free from concrete and not deal with the plastic sheet.

Concrete placement was done next. For this installation, the drain was centered in a 20″ wide excavated trench that was approximately 12″ deep. A minimum 4″ space was below the channel and 6″ on either side of the channel for concrete to fill. No reinforcing was used in the concrete (4000 psi mix). The concrete truck discharged the mix directly into the trench. Two men placed the concrete in the trench using hand tools. It would have been useful to have a pencil vibrator during the placement. Never-the-less, concrete pouring only took about one half hour.

Once the concrete was placed and the truck had left, the grates (with plastic sheeting) were removed and concrete finishing began. After removal of the trench cover, some clean-up of the channels was required using a wet rag. Trowels and edging tools were used in the finishing. Once the concrete began to set and finishing was complete, the grates were put in place and the lock bolts were tightened.

On the following day, some house-keeping was required to complete installation. Concrete forms were removed, dirt was placed in areas affected by the excavation, mulch was replaced, flower planters were put back construction rubbish was picked up and the asphalt driveway was power washed.