The Culture of Residential Concrete: Fighting the Good Fight
In the harsh winter of 2009 - 2010, many residential homebuilders experienced failed driveways in the Midwest. The concrete they had placed prior to the winter freeze scaled, and they wanted answers. Some complained that driveway failures were as high as 30% that spring, an unusually high number. These projects were so numerous they were brought to the attention of Jereme Montgomery, Executive Director for the Nebraska Concrete and Aggregates Association, for analysis.
As a result of these residential driveway issues, Jereme got together with the local Ready Mix producers, a few residential concrete contractors, and some passionate homebuilders, and created a working cross-industry group. This group’s mission was to assess the driveway failures and to seek a resolution.
TAKING CONCRETE INDUSTRY GUIDELINES TO THE HOMEBUILDERS
Jereme went in front of a Midwest homebuilders’ group that spring to address these concerns and failures, and to communicate minimum industry requirements regarding durable concrete. He quoted concrete industry guidelines straight out of ACI’s manuals on maximum water-cement ratios, proper curing methods, durability in freeze-thaw environments, not over-finishing the concrete, proper air requirements, and so forth. To say most of the audience was rather suspicious to his testimony is an understatement.
Despite the tough crowd, he soon discovered that some of the builders listened and changed the way they constructed driveways. They took him up on his advice on selecting higher quality concrete mixes. They maintained proper water-cement ratios. They started curing the concrete after placement. Some even began to protect new residential driveways from water and salt intrusion with penetrating water repellents, such as L&M’s AQUAPEL.
Despite having newly minted concrete standards promoters in residential homebuilding, Jereme isn’t wildly optimistic that residential driveways will be properly placed and finished in the future. He thinks driveway scaling will continue because the finishers placing the residential concrete are not getting paid to place quality concrete. They’re getting paid to “finish it and forget it.” Jereme stresses to the builders that if they want better quality driveways, the concrete laborers have to be paid to produce quality work. To change this environment requires a cultural shift, a new perspective in the way residential builders think about and sell concrete driveways
OFFER THE HOMEOWNER CHOICES
Homebuilders ought to consider the following questions as an alternate way to sell concrete to the homeowner: “Do you want to upgrade your driveway’s concrete? Do you want a more durable mix? Do you want a salt and water repellent applied to make your driveway last even longer? Do you want some customization in to your driveway? Do you want color?”
This is a great way to go about changing residential concrete specs because everybody gets paid. Additionally, the average homeowner simply lacks concrete education. If the typical homeowner were given choices about their driveways and patios in the design phase, they’d seek further education on the subject, prompting good questions about concrete quality, longevity, customization, and so forth. These are choices most homeowners don’t even know they have.
DURABILITY IN MIX DESIGN
In Nebraska, most of the residential market concrete mixes are sand and gravel mixes, which are inexpensive due to the state’s natural surplus. However, this doesn’t mean that the mix is freeze thaw durable. For example, a concrete contractor wouldn’t place a grout mix in driveways. In a mix design comparison, sand and gravel mixes are one step above grout. It takes a lot of water to get to a 4” to 5” concrete slump with a sand and gravel mix. The current industry standard is nothing more than 0.45 water-to-cement ratio. This is the maximum water content allowed according to ACI 332-14 for concrete subject to moisture and de-icing. In standard sand and gravel mixes, the water-cement ratio ranges may exceed industry requirements. The mix design plays a huge part in concrete durability right from the start.
COMPARING THE RESIDENTIAL CONCRETE MARKET TO THE HEAVY HIGHWAY CONCRETE MARKET
It is interesting to compare the heavy highway concrete market to the residential concrete market. In heavy highway, they have very tight specs. Everyone is expected to bid according to the specification. They test for concrete strength by doing core samples. The heavy highway market has quality assurance. Contractors get fined if their work is not up to certain standards. In short, the heavy highway concrete market is highly controlled and standardized. Unexpected things still happen, but are minimized through proper quality assurance programs. Conversely, most residential concrete markets have none of these standards, no regulations, improper specs, nothing to ensure quality concrete in driveways.
standards are currently trending. According to Randy Stark of Consolidated Concrete, “while the residential market quality has gone up, it is an ongoing process [of changing the culture]. The most success we’ve had is having a sit-down with admix producers and have them present to the flatwork guys what’s going on. Through NC&AA and the ready mix producers, we’ve offered training to flatwork customers.”
Stark continues, “We like to have concrete professionals like LATICRETE L&M teach our customers about the importance of curing and sealing concrete, and its fundamentals.”
About the Author:
Jereme Montgomery has a Bachelor of Science degree in Construction Management from the University of Nebraska. He has over 18 years experience in concrete. Since 2006, he has promoted concrete and aggregate products as the Executive Director for the Nebraska Concrete & Aggregates Association. He is also past President for the American Concrete Institute-Nebraska Chapter and current member of the Construction Industry Advisory Council for the Durham School of Architectural Engineering & Construction.
He runs a concrete industry podcast called Concrete Garb. To subscribe to his podcast, visit: http://www.concretegarb.com/thebirdsnest/
Executive Director, Nebraska Concrete & Aggregates Association
5700 Seward Av, Suite B | Lincoln, NE 68506
© 2015 L&M Construction Chemicals, Inc. | ConcreteNews Summer 2015.