If you aren't already familiar with ThruFlow™ you may wonder why does the surface have holes ? There are many advantageous to holes:
- They are speficially designed to comply with ADA requirements
- They let the sun light pass thru, and seagrasses, bog plants, and dune growth like that a lot
- They let rain water run thru, which reduces runoff
- They let storm tide rise up thru the decking material thereby reducing uplift in storms
- They make the material lighter, you'll thank us when your boss tells you to carry 100 pieces to the backyard
- They conserve material, and what could be more green than that
I have always looked at things and wondered, why did they do it like that ! Let's do that with ThruFlow. I hope I'm not giving away all ThruFlow's secrets.
Why are the holes in ThruFlow oriented across the path rather than with the path of the dock or pier. Of course if you turn a piece of ThruFlow™ upside down you start to see some of the reasons. The Plastic molded in Ribs run across the span that will rest on the stringers of your dock, deck or pier. That offers structural span strength, albeit across the short 15, 16, or 18 inch span from stringer to stringer. If the openings were rotated 90° from their current location you could not put nearly so many ribs in the structure. The panel would be much less strong.
Also, a requirement of the ADA ( American Disability Act ) which specifies that any openings in a walkway or ramp shall be less than 1/2 inch in the direction of travel. Its just 0.40 inches which meets this particular requirement.
Another thing, I've seen some deck material that has dizzying wavy patterns that give me vertigo even when I'm not walking over the water. ThruFlow on the other hand has a disciplined regular pattern. When you put it down in a long path its look changes to a pleasing texture. I think it looks disciplined and handsome. People got used to those classy stainless kitchen appliances pretty quickly. Did they look commercial ? I'll insert a picture of a ThruFlow™ deck around a pool, tell us what you think. I think it looks pretty good, as do the installed docks and piers I see.
Let the Sun Shine Thru
One of the first uses of ThruFlow was at the suggestion of the ACOE (Army Corp of Engineers). As it turns out, some sea-grasses are endangered, one I recall in particular is Johnson's Seagrass, however different areas of the nation have different species to be protected. In some areas they require light transmitting materials ( LTM ) based decking to reduce shadows for predator fish to hide in.
If you put a dock or pier over the water where sea-grass or other aquatic vegetation is growing, the reduction in light will reduce the growth. ACOE after much deliberation determined that the decking material must have 43% open area on the surface. ThruFlow™ meets that criterion.
There have been a number of papers written by the ACOE Jacksonville office that I am aware of. [ACOE PDF Here] . A quote from the article is:
"A type of plastic grating is manufactured by ThruFlow Interlocking Panels (1-888-478-3569). ... Panels are available in a variety of sizes and thicknesses. For safety, the grate should contain an anti-slip texture which is integrally molded into the top surface. The manufacturer or local distributor should be consulted to ensure that the load-bearing capacity of the selected product is sufficient to support the intended purpose. Contact the manufacturer(s) for product specifications and a list of regional distributors."
I don't like to think that engineers will specify, nor contractors install, nor end users desire, ThruFlow just because they are told they have to use it. There are many other benefits of ThruFlow which are detailed in this article and on this site.
ThruFlow has extensive studies of the various conditions and the light left to fall on the water's surface. Here is a PDF report off the ThruFlow Site LightPenetrationTest .
Pave the World Over, Not !
Some people occasionally speak with some disdain regarding our civililization's propensity to cover the planet with concrete. I have read of some municipalities that have required porous sidewalks. In areas where you might be designing in a wide ADA compliant dune crossing, nature trail or other raised improved passage way over vegetation, allowing the rain water to drain right thru can't hurt.
A Rising Storm Tide Lifts All Boats -- And Your Dock Too !
On the ThruFlow website there once was a testimonial from a customer in the Florida Keys. His ThruFlow dock survived the hurricane tidal surge while neighbors on both sides had their lumber decking based docks destroyed.
[ embed testimonial here ]
Common sense tells us that letting the water rise through the deck rather than trapping it will reduce the forces. This situation is further exacerbated by the requirement in many areas that the dock's deck be 5' above mean high tide. If the dock were low enough, the early surge would cover the dock and that in itself would offer a lot of protection for it. However, at 5' it may be at almost the worst level.
ThruFlow is a Heavy Weight When It Comes to Light Weight
ThruFlow is offered in 3' x 1' , 4' x 1', 5' x 1', and 4' x 4' panels. These are 4.2, 5.4, 7.0 and 24.0 pounds respectively. I guess if a dock contractor told you he could carry 10 feet of decking for a 5 foot width dock from the truck to the backyard, you'd want to see it. Not with Pressure Treated Lumber, that's for sure. 70 lbs, that's under the UPS limit.
I am told that some places way up north have solid water in the winter in their lakes and rivers. They have to bring the dock ashore every winter. Light weight means a lot to them. A temporary event dock would benefit in the same way.
Also, [ No Profile ] do they have the ThruFlow version yet ?
Highly Engineered, Minimal Material
When I hear people talk about 'green materials' there are all kinds of attributes or requirements for them to label something as being Green. My first car was a very used 1964 Volkswagon Bettle stick shift with no AC (and might I add, barely a heater). I have always valued efficiency, and that VW got somewhere around 30+ miles per gallon, and that was important to me. I remember gas was right around 30 cents per gallon.
I've always valued efficiency for efficiencies sake. I parallel efficiency with what people today call green. After all, grandma told us "Waste Not, Want Not". Pretty good advice for saving the planet, or what ever you have in your wallet for that matter.
If you look at the underside of thruflow you'll see molded in plastic ribs of considerable depth, interlinked with cross members. The top walking surface bridging the ribs is pretty thin but under the surface cylindrical stiffeners, but more than adequate as a walking surface.
Whether it is a bridge or a dock, in today's world almost all engineers start out with a requirement in terms of loads, the engineers determine suitible spans, beams and materials. There is alwlays present the goal to reduce costs which leads to using as little material as possible. When you think about it, minimizing material is in itself a concept compatible with 'Green Goals'. Furthermore, there is nothing to leach out, such as there is with Pressure Treated lumber.
ThruFlow is FRPP (made of fiber reinforced polypropolene) and can be recycled, but its going to be a long time before you want to do that. The warranty is 12 years ( see Thruflow literature for details) and estimates are that this material is likely to have a service life of 30 years.
Unlike many materials ThruFlow does not contain recycled material. If it did, it could never be as lightweight as it is. ThruFlow panels are 'Highly Engineered' and that requires the material that it is made from to by uniform and very reliably controlled. Its made of only the finest materials from suppliers with the highest quality control.
ThruFlow loadings are well over 100 lbs per square foot, when applied per ThruFlow's specifications 100 lbs, 135 lbs, 170 lbs loading, for the 3', 4', and 5' panels respectively.
