Green Roofs - Living Architecture Monitor - Summer 2012 - (Page 12)

CURRENT RESEARCH INDUsTRY PROFEssIONALs wEIgH IN ON gROwINg MEDIA qUALITY CONTROL gROwINg MEDIA Is A CRITICAL AND OFTEN NEgLECTED COMPONENT OF A gREEN ROOF PROJECT, PROBLEMs wITH gROwINg MEDIA CAN COsT UPwARDs OF TENs OF THOUsANDs OF DOLLARs, IF NOT MORE, TO REMEDY AFTER INsTALLATION! CHUCK fRIEDRICH, GRp, RLA, ASLA, CAROLINA STALITE COMpANy A very good friend of mine once told me to “watch out for pigs eating ham sandwiches”. On more than one occasion I waited for a purchase order that never came, only to find out that the specified Stalite growing media was substituted with “Brand X”. For those of you that know me, that was not a good day for said contractor. There was actually one project where I found local fill dirt on a roof. This scenario can be avoided if those in charge understand that growing media is an engineered substrate and not a soil. However, what if it is those who are managing the project that are pulling the old switch-a-roo? Landscape Architects that are not being paid to manage projects usually surrender that duty to the general contractor (GC). When the money runs low, the inferior “Brand X” makes its way onto the roof under the “value engineering” excuse. This clandestine operation can also be an arrangement during the bidding process between the GC and his accomplice (the favored subcontractor) under the guise of “approved equal”. When this occurs it is always fun to sit back and watch the show. We are all aware this happens, so how do we ensure that growing media that is specified is the same growing media found on site? What if all you have is a performance specification, especially one with a wide range of nebulous FLL parameters? The only way to prove that it is the real deal is to test it again on the job site, and again- and again money money. Anything can be tossed into the mix as cheap filler between the time the truck leaves the blender and when it makes its way onto the roof. I would not rely on gimmicks like colored indicator chips because they do not set off an alarm that the mix has been tampered with. When it is on the roof, how do you know you got the real deal? Stalite has always provided their proprietary recipes for the whole world to see; “a percentage of this and a percentage of that” and so on, so visually it is very recognizable. MIKE CURRy RLA, ASLA, GRp SALES & MARKETING DIVISION MANAGER MIDwEST TRADING HORTICULTURAL SUppLIES INC. Only purchase media from a high quality, reputable and experienced soil blender and TEST IT! Quality control sampling should be required in the specification, and samples should be pulled during the production of the media according to the spec. If there is any question, or as standard procedure, these samples can be tested and compared to the spec, the material on site, and to the original submittals. The sampling and testing methodologies should also be specified and followed by the manufacturer and anyone collecting samples of the material on site. Inconsistent sampling methods could cause deviations in test results. Similarly, the same testing laboratory should be used for all the samples being tested on a project in order to minimize inconsistencies in the results caused by variations at the labs. In addition, lab results can vary from test to test, and from line to line, even on the same composite sampling. It is also a good idea to have a qualified individual evaluating the lab results to determine if any variations are within what would be considered a standard deviation for that particular media, or if it is a different media altogether. KEES GOVERS, GRp, bSC.AGR, TECHNICAL SALES MANAGER LIVEROOf ONTARIO INC As a green roof supplier/manufacturer you have to start with a proven and tested growing medium, the blending recipe for which needs to be adhered to rigorously. A good consistent formulator is the next requirement. Not only is adherence to the mix recipe important, so is cleanliness. A good growing medium full of weed seeds LIVING ARCHITECTURE MONITOR / SUMMER 2012 / 12

Table of Contents for the Digital Edition of Green Roofs - Living Architecture Monitor - Summer 2012

Green Roofs - Living Architecture Monitor - Summer 2012
Letter from the Chairman
From the Founder
New Standard on the Use of Lightweight Aggregate
Urban Agriculture Declaration Caps Amazing Summit Debut
Economics of Biophilic Design
Brad Rowe, David Spalding, Cornelia Oberlander, Paul Kephart
Green Roofing Industry Sees Triple Digit Growth
Green Roof Local Market Symposiums
Industry Professionals Weigh in on Growing Media Quality Control!
CitiesAlive in Chicago Oct 17th – 19th
Green Infrastructure Ontario Coalition Changes our Perspectives on Infrastructure
Improving Tax Abatement
10th Anniversary Commemorative Pull Out Section
Halifax Seaport Farmer’s Market
Leadership Knows No Bounds- Virginia Russell
Policy Profile- A Home for Biodiversity on Green Roofs
New Industry Products
Plant Profile: Chives Thrive on Green Roofs
Half a year, Full-Fledged Growth
In God We Trust – All Others Bring Data!
New Corporate Members
Professional Calendar
GRHC Buyers Guide
Green Supremacy by Zach Williams

Green Roofs - Living Architecture Monitor - Summer 2012