The Simons Institute for the Theory of Computing has a new home in the Melvin Calvin Laboratory building on UC Berkeley’s campus. And skirting the southwest edge is a new polished pervious concrete path! The next time you find yourself on campus, I hope you bring some water and pour some out on their new pervious path!
This is where the path is adjacent to Optometry Lane.
Polished Fine Pervious Installed in Los Altos Hills!
A new residence has installed a pervious concrete driveway - but what is special is the size of the aggregate! It is a 1/8 inch aggregate that polishes up beautifully! You can see this incredibly smooth and polished look starting at the gates and sweeping up to the front of the house. Pervious concrete is also featured around the parking pad in the back and there is a wonderful view of the valley below. All the photos in the gallery below!
Read MoreSausalito Fairytale: Harrison Park
Harrison Park, a tiny oasis in the residential area of Sausalito boasts one of the only playgrounds in the city, as well as a pervious concrete path! Take a look around and the next time you are there, check out Harrison Park in the hills of Sausalito!!
Have you been? What do you think? Let us know in the comments below:
Stormwater Sleuthing - Episode 2 - Palo Alto
David Liguori is back in the field, this time comparing a long sloped asphalt driveway with a neighboring long and sloped pervious concrete driveway during a rainstorm last year.
What did you think? Do you have a Stormwater Sleuthing location (in the Bay Area) that you would like David to investigate the next time it rains? Let us know in the comments below or contact us here. Thanks!
USGBC Greener Builder - a fantastic conference!
This was originally posted June 19, 2013.
Lauren Wray, our Director of Marketing, attended the USGBC’s Greener Builder Conference last week. Apparently the Greener Builder Conference is even GREENER then the Green Builder Conference that occurred in November! This conference did not disappoint. From the opening panel, pictured below, featuring Jeffrey A. Birdwell, Michael Deane, Kevin Hydes, Kirsten Ritchie and moderated by Cliff Brewis, the focus was on leading edge sustainability, and strategies to get regenerative planning and innovation into the building industry.
There were good options for every panel, but as pervious concrete sub-contractors, we went to the subcontractor panel, hosted by John Home and Jeff Swinyer of Rudolph and Sletten, pictured below.
Lauren, pictured below, was interested in the drive toward clear performance specs to allow for differentiation at the sub-contractor level. As a pervious concrete subcontractor, we differentiate ourselves with our embrace of leading edge technologies for mix design and installation. Unfortunately, many current specs don’t reflect the progress in the installation, mix designs, equipment and curing materials that has developed in the last few years.
The next panel we attended discussed Environmental Product Disclosures (EPDs), a labeling system that discloses the resource footprint of the many materials that go into the built environment. The panel also included the next iteration, the Health Product Disclosures, which discloses the materials and chemicals that have been proven or correlated in causing health problems for humans.
Central Concrete, a sponsor of the event, has been heavily involved in the EPD project for disclosing the materials for the concrete industry. Below is a photo of the panelists from this panel.
The last panel of the day went over Net Zero Energy buildings with John Andary and Scott Shell, pictured below. It was a fascinating look at what is currently possible with technologies now: buildings that use as much energy as they make. The building case studies discussed also illustrated how livable and workable these spaces were, with thought for passive heating and cooling. Many of the designs features windows that bounced daylight far into the building envelope, as well as fresh air ventilation. It was a wonderful talk, even though their topics stayed primarily inside the building envelope.
The final speaker, Jason McLennan, pictured below, gave a wonderful talk on self limits. His talk really stood out for his candor and optimism. For a young guy, has accomplished quite a bit in the green building spaces. Currently he is pioneering the Living Building movement.
After his talk, Jason McLennan was joined by George Salah, of Google, and David Gottfried of the USGBC. They discussed everything from George’s living-building home construction project to Jason’s motivation to do the work that he does: “I give a shit.” That was wonderful.
FInally, after it was all over, we found that there was a fantastic array of beers, wine and snacks to round out the day’s networking. It was a great event, and one we will look forward to attending next year!
A BIG thank you to Charlie Nucci, who took these photos at the event. You can find more about Charlie and his work at his website here.
NRMCA Technician Training in Truckee - A Success!
David teaches the NRMCA Pervious Concrete Technician class by the NRMCA local sponsoring group ACI Northern California chapter. The class location was in Truckee, CA and after the class and test, the class went out the TNT Materials Yard for a demonstration pour. We had good pervious pouring weather and great participation! If you would like more information for upcoming NRMCA pervious concrete training classes, go to the ACI website here: www.ACI-NCAWNV.org.
Check out the photos below:
Graniterock Quarry Tour - with Photos!
The Bay Area Pervious Concrete team went to visit Graniterock at their Aromas location. Lauren arranged for a tour with Graniterock with their testing group. We piled into a car wit Katha and Greg, both in the Graniterock materials testing group. First we went to visit Big Bill, the massive material spreader.
Big Bill (pictured above) was at the end of a 3mile conveyor belt bringing material from the waste end of the crushing processing to the spreader. The wheels were at least 10 feet in diameter! It was a massive machine! The material being spread looked like moon dust!
After leaving Big Bill we went into the quarry. You could see the step-like traces of material that had been removed. The terraces started at the top of the hill and went rather deep, below sea level! There was this massive truck (pictured above)that was moving the 'raw' rock and rubble close to the initial crushing machine (picture below). The crushing machine was in the quarry and it was even more massive then Big Bill the spreader! Here are a few photos of the team with the crusher. It was not running at the time, I would imagine it would be deafening! From the large initial crusher, another conveyor, shorter then the 3 miler, takes the material to the processing yard.
The material on the initial conveyor is then sorted into two sizes (big, for dry processing, and smaller, for wet processing) before being further sifted, crushed and rinsed to final product sizes and blends. The processing yard was a maize of conveyors, buildings on stilts (the crushing/processing/screening) and piles of material. Going into their control tower, we could see the levels of complexity and organization to keep all of that machinery moving that went unseen in the maize outside the windows. Even further beneath the surface of the processing yard was another conveyor in a tunnel beneath the main stockpiles, to allow for high control of the custom blends and product development.
Graniterock's newest addition to the quantitative analysis even had this fabulous quality assessment program that noted the size of final aggregate moment to moment to ensure consistency of the final product. They could, in real time, plumb their data and understand how consistent their product was, and make appropriate adjustments to bring it back into line. That type of feedback allows the quality team to be responsive to current inventory as well as give the operations team insights as to how well their processes are processing. It was a fantastic set-up, although I may be a data geek.
It was a fantastic tour of a great facility. We learned a lot about the aggregates that we use frequently in the Peninsula as well as how it gets to us. Really good quality rock makes even better pervious concrete! Please send us comments or questions! :)
Water Conservation Showcase a success!
Our own Lauren Wray attended the USGBC and P&E’s Water Conservation Showcase this year. The Bay Area Pervious Concrete Booth was in this video, above, and photos of Wray and pervious concrete made it into PG&E’s “Currents”, a P&E news site. Check out the video and let us know your thoughts! Did you attend the Water Conservation Showcase this year?
The Rational Method and Pervious Concrete
The Rational Method is used by many storm water civil engineers to understand storm water runoff. Frequently it is being invoked to understand the impacts of pervious concrete. Frankly, the Rational Method has no place designing with pervious, and this is what we are going to discuss.
The simplest reason being, the Rational Method is there the allow engineers to size the necessary sewer line appropriate to the runoff on the site. However, when pervious concrete is well designed and installed for most or all of the parking or access areas, there will be no runoff from that area. It is even possible, pending some limitations**, to capture most if not all of the adjacent runoff from impervious roofs or other impervious. That would make the runoff coefficient 0 or even negative. Given that, Q becomes zero, or less then zero. At that point, no drain pipe is needed to carry away the storm water, and the Rational Method is not the appropriate method for quantifying storm water.
This hints at the total shift that is before us - the way we previously understood hardscape and the associated negative externalities (runoff, storm water pollution, heat island effect, aquifer depletion) is turned on its head. Now these previous negative externalities are accounted for and reversed, and we are able to maintain the preferred hard & durable surface with pervious concrete. Pervious concrete allows storm water and pollution to filter in and infiltrate, allowing microbes and soil to be the filter that they are for the rest of nature. Pervious concrete mitigates the heat island effect in 2 ways, having a high solar reflectivity index as well as allowing a water and air exchange between the soil below and air above the pavement.
But given that codes are still being written, and some building and design professionals do not know about pervious concrete and its benefits we must still use the Rational Method. So I propose a stand-in coefficient.
To review the Rational Method for those of you who don't use this equation frequently,
Q = the necessary size of the pipe to capture the runoff being generated by C, I and A.
A = The area whose runoff is being measured.
I = The rate of rainfall in a given time horizon.
C = The coefficient that is determined by the type of ground covering being measured, below you can see one version of the chart referenced.
As you can see in the above chart, [impervious] paved surfaces gave a runoff coefficient of 0.94 for the 5-year storm event. Toward the bottom of this chart, "Lawn" and "Parks/Golf Courses/Cemeteries, 8% impervious" have a runoff coefficient of 0.21.
As far as I know, there is no such coefficient for pervious concrete to be used in the Rational Method. On the one hand, it isn't really necessary, as infiltration hardscapes may make the Rational Method less necessary. Or, perhaps the Rational Method will be adapted to vet and verify successful implementations of LID measures. In the meantime, it seems that a stand-in number is necessary - what if we were to use the "Parks/Golf Courses/Cemeteries, 8% impervious" 0.21 as a reference, and then include the >0.21, as it is less then 0.21, however it is unknown how much less at this point, for research has not yet been completed.
What do you think? Is this a reasonable way to discuss the Rational Method and pervious concrete?
** The limiting factor when dealing with pervious concrete is the subbase soil’s infiltration rate. Given enough area and enough reservoir base, it is possible to infiltrate a serious storm.
If you have more information please contact us, and we would be happy to discuss this with you.
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Sources: chart http://www.iowadot.gov/design/dmanual/04a-05.pdf
conversation and cocktail napkin - inspiration to post
Pervious Patio at the Hyatt Regency SFO
The Hyatt wanted a new look and feel for two areas on either side of a walkway that connected the north entrance and the parking garage. They wanted to rip out the existing plants and replace it with a usable patio space. They also wanted pervious concrete - so they called us!
After we installed the Polished Pervious® concrete, we scored it, completing the look. The Hyatt put out this sleek and modern furniture, turning this previously unusable corner into a nice place to take a break! Below is the larger area, to the east of the pathway.
Stormwater Sleuthing - Episode 1 - Woodside Runoff!
David Liguori went out into the field, during the last rain, to see what the stormwater runoff situation looked like in Woodside, California. Watch the video below to see what did and didn't run off!
What did you think? Do you have a Stormwater Sleuthing location (in the Bay Area) that you would like David to investigate the next time it rains? Let us know in the comments below or contact us here. Thanks!
I Spy Video on PERVIOUS CONCRETE!
25 objects in just under 3 minutes -> How sharp are your eyes?
We have created an ISPY video on the World's Longest Driveway! Can you find all of the items listed below? Feel free to send this link to the keenest eyes you know. Use the full screen option, to catch all the great details! It took me 3 tries to catch everything - how many did it take you? A list of the items is below the video.
Egg carton, Buzz Lightyear toy, V8 bottle, Clipboard, Rubber rat, Hammer, Talking lizards, Santa hat, Manila envelope, Wall-E figurine, Hackeysack, Tennis shoe, Hardshell glasses case, Blonde doll in a pink dress (polly pocket), Rubber chicken, Stack of CDs, Newspaper, Pliers, Roll of tape, Magnifying glass, Padlock and key, The Lost World paperback book, Stuffed animal monkey, Spray bottle & Bar Simpson doll
How many objects did you catch the first time?
Pervious concrete and trees
How close can you pave to a tree?
Normally, it is inadvisable to pave inside the drip line of a tree. Depending on the size and age of a tree that can be a fairly sizable area. This can be problematic when traffic or use requires paving close to the tree. When traditional impervious pavements are installed near older established trees, it can spell the end of the tree. Is that true of pervious concrete?
It turns out there are two students at Texas A&M are doing this very research! Their recent work reveals pervious concrete does, in fact, enhance the growing conditions of established trees relative to traditional concrete. They poured traditional concrete around a few established trees, pervious concrete around a few established trees and left a few trees with no cover for the control, and measured tree health for a little over a year. The results: the trees surrounded by the pervious concrete had more trunk growth during the year then the trees surrounded by the traditional concrete!
What does this mean for you? The good news is that you can integrate pervious concrete paving into plant friendly parking lots and hardscape design, knowing that you are not compromising tree health. This also may open previously impossible parking or other paving possibilities due to the ability to extend the pervious concrete closer to the tree, well within the drip line. Yes, it can make installation tricky, but it can be done!
The takeaway is that pervious concrete is great for protecting mature trees. As you can see above, our clients think so too!
You can read more about pervious concrete effect on trees and their growth by reading the Texas A&M research paper listed on our Resources page.
2 Symptoms of Failed Pervious Concrete
2 Symptoms of Failed Pervious Concrete - Raveling and Sealing
Recently it has come to our attention that there appears to be a discrepancy in what a high-quality pervious concrete jobs looks like, and what has been passed off as high quality but in fact is not at all quality.
Failed installations have 2 main features: raveling and sealing.
Raveling is when the aggregate comes off of the slab as cement coated gravel. That can be an indication of poor mix design, poor installation technique or even misunderstand the weather's impact on the day of the pour.
Sealing is when the water pools and does not go through. It is possible to have sealing at the top, where it looks blotchy, or just beneath the surface such that the finish looks appropriate but does not drain. This is an indication of poor mix design. An experienced pervious concrete installer understands how critical the proper mix is and works closely with his ready-mix partners to get it right.
As we at BAPC have said before, pervious concrete is a tricky material and only those who are qualified, experienced and show a commitment to ongoing learning about techniques and mix designs are able to install and place pervious concrete with a consistent high quality.
We have created this video, complete with an amazing sound track, to illustrate what failed pervious concrete looks like, and what successful pervious concrete looks like. If you would like us to come out and evaluate your slab, or better yet, if you would like it done well the first time, please contact us.
The GREENEST mix - Pervious Concrete can get GREENER
The Greenest Mix we have ever devised!
Guest post, written by David Liguori
I wanted to give you a quick update on one of the more significant developments we’ve achieved lately.
In our continuing quest to further improve the performance of pervious concrete we have developed an “ultra-green” mix design for which we have recently received test data. The mix contains only 245 lbs. of cement, vs. 5-600 lbs. for regular concrete, and 245 lbs. of supplementary cementitious materials (scm). The scm consists of a combination of fly ash and slag, both industrial waste products.
We used this mix this past January on a 2,000 ft. long (by 10’ wide) driveway in Palo Alto(photo above) and 3 months ago on a 5,000 sqft. driveway in Los Altos Hills (photo below). They are both performing quite impressively. Absolutely no surface raveling, all of which typically takes place in the first month or two if it’s going to happen, water infiltration rates of 700-1,200” per hour and compressive strengths above 3,000 psi.
As I am sure you know the addition of the scm’s slows down the rate of early strength gains but ultimately results in higher overall strength. In the case of the ultra-green mix our 28 day numbers are in the 2,600 – 2,900 psi range and to our delight the recent 90 day test came in at an outstanding 3,520psi. These type of results and data continue to increase our confidence in pervious concrete as viable long term stormwater management solution.
If you would like more details, contact us here and we will get in touch!
xx
This is the video from the longest (and greenest) pervious concrete driveway in the world!
Bunyan Pervious Roast 2012 - Hot days in the desert!
Bunyan Pervious Roast 2012 - Just outside Las Vegas
Out in the Nevada desert, outside of the Vegas we know is a far dustier affair known as the Pervious Roast. Dave Mitchell and team put together a spectacular 3+ days of speakers, pervious pours and food, which by all accounts was very informative and fun.
Our own David Liguori spoke at an un-scheduled moment to go over what goods and the not-so-good installations look and sound like. The video will be posted in an upcoming blog post. There were also presentations from Scott Erickson of Evolution Paving, and Jereme Montgomery.
BAPC's Rob Estrada was able to snag a picture with Matt Offenberg, of bell-ringing fame. You can see how glad they are to head into the (air conditioned) NRMCA meeting.
~ Update: Lauren Wray
- Photo Credits: Robert Estrada, David Liguori, Lauren Wray
RC Ready Mix - Sample Slab with Decorative Pervious
We teamed up with RC Ready Mix to do a sample pour over in their yard, with their aggregate. They wanted to see how it went down, and we wanted to see how our mix design would work with their rocks. Not only did the installation turn out REALLY WELL, but Rob Estrada was able to really show us all a few MORE possibilities for decorative pervious concrete!
The first question is always ‘how well does it drain?’ Check out the video below to watch the front end loader dump a bucketful of water on the slab!
We agree with the driver, thumbs up! A few days later, Rob went over there to try some designs to see how they could look. We are well known for our Polished Pervious™, which you can see below, next to the Classic Pervious Concrete.
To get a closer look at the great texture, we took a close up. You can see the Polished Pervious Concrete ™, and then set into the pervious a pattern that was added well after the plastic was pulled up.
And here is where Rob really let loose! As Rob added these layers of color and texture to the Pervious Concrete, you can see the window that RC Ready Mix installed when they were framing. That allows one to see the water going through the layers of the Pervious Concrete System.
Here is most of the slab - you can see the suns and the moon and the gorgeous colors that were used!
If you would like to see this in person, it will only be in the yard for a limited time. Contact us for more information.
Pervious in Paradise 2012 - a recap!
The NPCPA’s First Annual Conference
Bay Area Pervious Concrete went to the US Virgin Islands for the Pervious in Paradise conference. David Liguori attended, because well, someone had to!
It was a great meeting with a small group with most of the attendees presenting content over the 2 days of speaker and 2 days of break outs. David presented on the Bay Are Pervious Concrete decorative finishes. We have a downloadable deck of our decorative finishes here.
The final day everyone gathered at a local school to pour a driveway with a local contractor. The concrete truck had to take a ferry to get to the island from the batch plant an island over. The mix was 2 hours old before it even arrived on the site! Fortunately, we had had many, many qualified folks to help offer guidance, work, shovel and supervise.
See you next time!
Tweet comments with @BayAreaPervious and @NPCPA #PerviousinParadise
Did You Say Decorative Pervious Concrete?
We have just compiled an entire gallery of Bay Area Pervious Concrete’s own decorative concrete innovations! Featuring everything from a metallic fleck, to our exposed smooth aggregate finish, and custom aggregates and borders. Pervious concrete no longer has to look like rice crispy treats. Visit our Bay Area Pervious Concrete’s Decorative gallery for all the hot looks!
Polished pervious concrete featuring integral color and metallic fleck finish
Give us a call or email us if you would like more information, a driveway or parking lot in the below finish, or an in-office presentation with samples!
Let us know what you think on Twitter.
A new parking lot at the Beth Abraham Temple
Monday we poured pervious concrete in the parking lot of the Temple Beth Abraham. Below are the finished photos.
