Let it Rain: Green Roof Implementation in the National Capital Region
Rainfall in urban areas can result in the overflow of local streams, rivers, and sewers. DC Greenworks Interim Executive Director Sara Loveland discusses regional rainwater-management concerns, the local legislative landscape, and opportunities for the federal government to increase their environmental stewardship by constructing green roofs and utilizing other low-impact development techniques.
Sara Loveland: Thanks everybody for coming out today and braving the rain. We joked earlier that you know, since Diana titled the lecture "Let it Rain," you know, perhaps that was the modern day equivalent via email of the rain dance. So, we got what we asked for which is great. The green roof outside looks really great so I do recommend that you guys check it out.
It's just going the dorm in C stages, but the rain is not too bad and the views are spectacular. So, if you have a chance you should go. I just wanted to start with a little about DC Greenworks so you guys understand my background. We have a very general mission, it's just to promote urban social revitalization through environmental restoration.
So, there are many different things that we could promote. Many different activities that we could be involved in. We happened to focus on low impact development in the National Capital Region over the last 15 years predominantly because the storm water issues are the ones that we find to be most pressing and they are also the ones that needed the most exposures.
So, people weren't really talking about them. And we felt there were a lot of ways we could do that and involve the community in a very sort of low tech ways. So, lots of opportunity there.
And our services to these extent include basically anything that will promote these issues. So, consultations, installation, advocacy, training, we basically do it all. Some of our recent accomplishments things that I think are applicable to you know, I guess viewing our operations. We have 35 people who have gone through green roof training.
This is a low tech training it's not a certification, but these means that they've been you know, present on job sites with us. They've learned to install green roofs. These are people just like yourselves. So, they come out as volunteers and we train them on how to install green roofs and then they oftentimes go on to start their own companies or they are already currently perhaps a Lead AP, and wanted to just see a practical application, you know getting their hands dirty of what they're doing.
So, a great opportunity for us. And other significant accomplishments for DC Greenworks, we've installed 50,000 square feet of green roofs. When I show you some of the numbers of what people are installing across the country later, you'll going to say 50,000 seems really small.
There are companies in DC who do 50,000 in a day. So, we do 50,000 square feet over many greater projects and the reason for this is that we try to take on projects that nobody else wants. So, the ones where there's no profit margin, the ones where the logistics are extremely difficult, the ones where you're dealing with the home owner and it takes a lot of time and a lot of education.
And those are the things that we like to do because we think that those benefits are tremendous. But then we do things as big as testifying for a senate sub-committee about what the benefits of green in the National Capital Region or what are some of the potential cost are. And we currently have $500,000 in grants under our oversight. These is for a number of different things including research and also management of DC subsidy programs which I'll talk a little bit more about later.
And we also most excitingly have developed a roof raising model. Roof raising model I alluded to a little bit earlier. He have people who are both unstaff and who are paid staff members who come to us and everybody works on the green roof, and everybody gets hands on training. So, everybody works construction at least part of their time.
We also have volunteer events which we call roof raising which are modeled after a barn raising. So, these is essentially a modern day urban equivalent of a barn raising where we have everybody come together, help build the green roof and then you celebrate it with a party and a band, and some micro brewed beer. And we don't take ourselves very seriously in these respect.
And I'd just like to outline a little bit of our vision and you guys can read these on your own, but we really felt like as we came in to a new administration and we felt sort of the social tides changing that there was going to be a lot more focus on urban impact as opposed to looking at suburban development.
And so, we now believe that the time is right for us to say, "Listen, if we're going to change what we're doing, if we're going to use more green infrastructure versus gray infrastructure. These are the ways that we want to see done and these are the priorities that we'd like."
And I think probably the most striking here is one that grows in strengthens the skills of our workforce in the green collar job sector because what we're talking about through implementation of low impact development technology is essentially fundamental shift in the job base in the DC region.
So, here is the main challenge there are 1100 communities across the country who lived -when I say communities these are predominantly urban concentrated, high density urban areas that have a combined sewer system. So, essentially what these means if you looked at the diagram. The diagram is showing you essentially what the system looks like without rain and with the system looks like with rain.
The really critical point here, people would know what a combined sewer system is. Know that we live in one. OK. That's half that's good that number is increasing. Actually, every time I talk the number is increasing which is fantastic. So, what these means is that all of the pollution that comes off of our streets, and then the pollution that comes through our toilets, through our sinks, through our industrial waste uses, all combines ahead of the treatment plant in our sewage systems.
And so, that's fine when you're running at normal capacity, but the minute that you have an extreme volume of rain that hits every impervious surface on every building, on every roadway, or every parking lot all of that water is going into the same system. And the system doesn't have the capacity to fund all of these. And so, where you see the water on the left hand side just you know, pouring over and going normally into the treatment facility.
On the right hand side what that's showing you is raw sewage being pumped into our rivers. And I'm not sure if you guys all caught the number that Diana mentioned at the beginning her introduction, but it's compelling. It's a billion gallons of sewage every year that we pumped directly into the Anacostia and the Patomic Rivers.
So, it's no wonder people make jokes about the terrible state of the rivers in DC. It's for good reason, it's not just one random error and factory of river that nobody is regulating. It's us, it's all of us everyday, every time we flush the toilet, every time it rains.
So, these is an ongoing thing. To manage that the Clean Water Act of 1994 mandated that all of these jurisdictions have a combined sewer overflow control policy.
Now, what these means to you is as you're bucking along any recreational areas along the river you see a sign perhaps that says, 'This is a sewer outfall zone." What that's advising you of in sort of fancy speak away from what's really happening is that raw sewage right here enters the river.
So, if you were to go into the river, if you were any of the fish in the river, or any of the other aquatic life, you basically are sitting in a toilet or worse depending on where it is located. So, there are those there are the signs, we need to issue advisories when there's a heavy volume of water and there are remediation plans.
Now, remediation plans which I'm going to talk a little bit more about in the district include gray infrastructure, and green infrastructure. So, gray infrastructure is roads, pipes, sidewalks, buildings, utilities of the built environment. They typically have one purpose. So, they managed sewage, they convey cars, they transport people. They do things like these.
And then there is green infrastructure which are living and moving pieces which often have multiple functions so they contribute to the community and they do things like process sewage or permidiate pollution. These particular graph is taken from the Green Infrastructure Foundation and I think probably the best visual display of the difference between gray and green infrastructure and what they contribute to society.
Hardware based and short life span for gray infrastructure. I know you guys have thinking, 'well but how about hi ways? They're long term right? That's not a short term thing'. But think of how often the hi ways needs re-paving. Now our office is in the H St Northeast Corridor and I'm not sure if ay of you have been there recently, but it's a major artery living the east side of town.
And the streets are like about as bad as downtown Baghdad. And that's not going to stop anytime soon. But, that street has only one purpose, it does nothing else besides convey automobiles. So, that's a great example of a gray infrastructure.
Now, green infrastructure with living parts, higher employment to capital ratio, these are the things we're talking about where we'd shift our job based from being people who are constructions workers laying pavement to being people who are gardeners tending plants.
Now, obviously that seems to be a fairly black and white comparison, but there are many degrees of - I don't want to say gray many shades of green in between there in moving towards the green collar job force. So, in DC the one I guess main overarching thing that I'll mention here and go through in numbers later is that our combined sewer overflow control plan is mandating a $2.2 billion gray infrastructure component which is a storage tunnel. So, where you saw the system here instead of increasing the capacity of the plant or finding other ways to stop water from reaching the plant for now essentially diverting the plant through a series of tunnels as large as Metro stations, which will hold several million gallons of water in the event of a rain.
And then just process it through the plant after the bulk of the storm has gone through. So, $2.2 billion for a storage tunnel if you do the math across District of Columbia residence, it doesn't really sound like a good deal for anybody right?
So, are you excited to pay for that? Anybody? OK. Awesome. So, the alterative to that is green infrastructure. Now all of these components are green infrastructure. We'll talk about green roofs specifically today. Is anybody here seeing one of these terms for the first time? I'm so impressed right now.
I hear bioswale a little bit.
Call it out don't be afraid bioswale. Bioswale is like a rain guard, and the difference is that a rain guard's focus is it acts more as a troff, and a bioswale is going to act more as a channel. And so, essentially the idea is to absorb water along the way, but it is still channeling and ultimately to some digestive form.
So, also pervious or permeable pavement, that's the other thing I'd like you guys to pay attention too. These is the difference between having actual materials that absorb water through them, and having materials like brick where you can absorb water in between them.
Although everybody should make a note that if you see brick sidewalks in DC that does not mean that they are either pervious or permeable because they laid them entirely of black top underneath those. So, there's absolutely no water permeate in the surface there. And also rain barrels which we install a lot of.
Those are I think probably fairly popular many of you know mystery back to the 70s, they're reemerging now. So, that we have a really great program called River Smart Homes in DC where you can have a rain barrel installed on your home courtesy of the District of Columbia government.
There's only a $30 co-pay. Also trees, and you guys will say, "Trees, oh everybody knows about trees that's easy. That's sort of the low tech thing." But you would be amazed how many people don't know that they need to plant a shade tree, to protect their homes.
So, we'll continue moving on and if you guys have questions about other techniques as we go through. At these point I'd like to recognize my staff members. This is Ashley Hannah, she sit on the second row. And then Ty Voyles is in the back here. If you have any questions about these technologies after the lecture are definitely welcome. Also if you'd like to approach them.
So, these are three example of green roofs that we've built in DC and it gives you an idea of the scope of our clients and both of the movement, I think. So, we have everything from the picture on the right hand side which is a garage in Georgetown where the client would work from home and had a studio in his home and he just looked out of the black tar roof everyday, and thought, "Well, I don't want to look at that. Couldn't I look at something better?" And so here you have a garden.
So, and people would say, "You're not really getting any energy benefits on your garage?" Yes, but you are getting the aesthetic benefits in the storm water management benefits. The other two buildings on the left hand side are both receiving numerous benefits from these. So, we'll talk a little bit more about this in the next side.
But, the list is pretty extensive if I went to the science behind all of them we could do like a two and half hour lunch and I was joking that we don't have enough Martinis on a Wednesday for you guys to take a two and a half hour lunch. So, we'll just move through them pretty quickly. But retaining storm water runoff is the one that we talked about most frequently and that's the case today.
Also habitat for repatriation of native species, and the favorite quote on this is that, "We murdered the habitat when we built a building." Right? So, these is our idea of trying to mimic that. We can't replace the natural habitats, but green roofs mimic the natural habitat that was there. So, it provides a more fertile breeding ground for things that we want to see in the cities.
Now, if they tell you that we want birds and bees in the cities I tend to get reactions like, "Birds, I like birds. Birds are great. But bees, I don't like bees. Why would I want bees." I think that the media in the past couple of years has brought I think to the mainstream the attention the focal point on why exactly we need bees and what the issues are of bees or not surviving and thriving. So, we should all want them to be participating in our urban corridors.
And also reduction and ambient air temperature is very important. There are several reasons for this. So, it contributes to a reduction heating and cooling cost because you're adding insulation to your building. Also because any mechanical equipment located on the roof is going to gain efficiency as a result of being located there and having lower temperatures.
Additionally on a larger societal benefit, it reduces the urban heat island effect which is the miles and miles of concentrated black top in impervious surfaces that are absorbing heat and continuing to radiate it throughout the day and making the average temperature in our cities several degrees higher than in the outlying ex urban and rural areas.
Additionally the increased life for the waterproof membrane and definitely should not be ignored if you only have to replace your roof every 60 years as opposed to every 20 years. Tremendous benefits for the building owner there. And providing aesthetically pleasing outdoor space. This is going to be the most important in the highest density neighborhood.
So, for example for a homeowner, you may have a nice area where you could retreat you in your roof or you may just use it for some of the other benefits we've outlined. But, if you were in a multi-family building or if you are in a commercial building these is amenity space. This is private outdoor space -the only that city dwellers get sometimes.
So, you really want this to be a highly functioning beneficial space for all the building users. And additionally the last thing I'll mention because these is sort of the shocker in the crowd pleaser is that solar panels operate more efficiently when the ambient air temperature is lower. And so, green roofs actually helped increase the efficiency of solar panels
Now, many people view solar panels and green roofs as competing products, but it's entirely possible to do an extensive or intensive green roof system and to do side mounted solar panels above a green roof system and you're going to get more bang for your buck that way. So, you're increasing your insulation,decreasing your consumption, and increasing your availability to generate electricity at the same time.
Now, these are the top 10 Metropolitan areas for green roof insulation in the last year and 2008. So, you'll notice that we come only behind Chicago and we think that we actually may overtake Chicago this year because it's been 2009 has been a very big year for green roofing in Washington DC.
And as you can see when the spread is only 30,000, it's not that hard to overtake them. One major project on one major federal building makes us the leader in North America in green roof implementation. And again when I was saying the numbers that maybe the DC Greenworks Installation numbers wouldn't be that impressive
.The town of Newton Square, Pennsylvania installed 48,000 square feet last year. So, that's probably their city hall or something that they decided to green and so in one day they greened more than we've done in our entire eight years of promoting innovative technologies. But, the enthusiastic and very cool thing about this is that, number one , you have a chance to be leaders, and number two, one of the reasons that we are on the top of that list is because we are now a policy leader as well.
So, it took DC a little bit of time to catch up on this, I'll be honest and I know as Washingtonians we all like to think that we're the center of the free world and we're leaders on everything, but really we were behind the curve on the green movement for a very long time and we've just now caught up.
So, there are several reasons for this but first I'd like to tell you a little bit about what the best policy is that's out there because these are the things that are probably or take away for working on other jurisdiction.
There is a density bonus whereby if you increase the amount of pervious surface on your lot you can add additional square footage to your building. This typically means you can increase the height if the building, you can increase the footprint in exchange for having more pervious surfaces.
So, if you build a green roof, you can build a bigger building. There are two things to be concerned about here, one is that you don't want to increase private green space on the top of buildings and decrease public green space on the ground level because that's a societal benefit where you have sort of a give and take there and you don't want it to be that the masses don't have green space, but the private few has many.
And additionally in DC the density bonus is not as much of a benefit because there are very few areas in DC where you can get any density bonus because of height restrictions. But what you can get in DC is fast track permitting, you can get this in several other jurisdictions across United States.
What this essentially means and it sound sort of cheesy is green light permitting. So, if you go in with plants for a green building, the city has made a commitment to help your plans get through the approval process faster.
These obviously as we all know can equate to dollars saved in time and money. And I think also just frustrations. So, that's the attractive benefit. There are also direct grant programs, we have several of these in DC now we have two actually. And there are couple of different ways you can get them outside of our subsidy programs.
So, for example if you have an interesting project on the headquarters of a non profit or on a low income housing project, or you know, something like this. You can potentially go to the Department of the Environment and receive large sums of money to do these demonstration projects. DC Greenworks is happy to help you do that and help you plan these projects.
But there's a lot of many out there that you can get just for having an innovative idea. So, don't think that everything has to be by the book. These is what the form is, and these are what the programs are. But, we do also have direct grant programs, so those are typically where we say we want to pay you per square foot. However many square feet of green roof you put in we want to pay you for that.
We being either the federal government or the local government often with money from the federal government from the EPI. And the reason they're doing this again is to offset the need for capacity in gray infrastructure. So, for every amount of green infrastructure we implement, we do have to implement less gray infrastructure.
Preferential loan programs are something that we're just starting to see develop here. Many of you may be familiar with them on the West Coast. This is how the solar industry got so big in California because banks in jurisdictions worked together to provide preferential loan rates or to provide loan rates that were backed by city bonds, things like these.
So, that homeowners could do things to generate alternative energy. And in this way it was a very simple payback calculation because you could say I will generate X kilowatt hours. I was paying Y for these kilowatt hours. So, my loan payment should be no greater than V. But, when you're talking about energy savings, it's a little bit different.
And so we I think on the East Coast are starting to have some really interesting programs in the works. And I would recommend that you check out the energy zone in the Annapolis if you think that you are looking for a loan product because we, I believe will have a similar product coming here soon.
And also there are storm owner fee credits, so I'll talk a little bit more about storm water fees in the following slides, and I think that will give you an idea than in the fact that credits are not really a true incentive on their own, but they will become. So, additionally in the local landscape we have many photo facilities installing green roofs.
Now, they do these for a number of different reason, but recent very large scale installations include the Department of Transportation, the EPA, the Department of the Interior, and the Smithsonian. So, thank you to the Department of the Interior for hosting us today. And they have installed the 5,000 square foot green roof outside.
And I'm told that they're going to be installing tens of thousands of square feet of green roofs on the rest of the building as part of their capital plans in the next two years. So, this is very exciting because it's a historic facility as well. They will be the first historic facility to completely retrofit their building.
Additionally there are private companies that are demanding green office in retails base. Most of these are shareholder mandates, but a lot of these can filtered on to you guys as well. So, make demands when you're buying products. Make demands with companies that you're doing business with. Tell them that you want them to be green.
It starts as simple as that and then it gets larger and then they're looking for green office space before you know it. And then every building has to be green. And additionally the DC Green Building Act supports green roof implementation to some extent, but because it really only applies to new construction and very large significant renovation. And only mandates lead silver.
We don't really feel that it's strong enough to make any significant impact on storm water issues. So, we also have as I mentioned the DC government leading the way. Now the outline of the programs that are available currently $5 per square foot up to $20,000 for small buildings. And now that is administered by DC Greenworks.
So, if you're interested in receiving a green roof grant and you own a home, a small business, any of these smaller buildings who would be eligible. So, up to 4,000 square feet in footprint. You can talk to Ashley about the application afterwards and she'll make it really easy for you.
The new program that's just being announced this week is run by the Anacostia Watershed Society, it's $7 per square foot and there is no limit to the amount that they will finance for any roof over 5,000 square feet. So, now you're talking about a really big pool of money here obviously because they're starting at $35,000 in subsidy.
And if you are in a commercial or multi family building most likely your footprint is 10,000 square feet or greater. So, we're talking about $70,000 being the starting point. Now, the reason the district is doing this is two fold. There's one, the EPA Clean Water Act combined sewer overflow agreement or control plan agreement.
And then there is also the implementation of impervious surface fees. So, impervious surface fees comes as part of the stir design to make the polluter pay. These is the best system that we've seen. It's being in acted all across the country. It's being passed fairly rapidly now through almost every major city council.
It struggled a lot in the late 90s and the early 2000s, but it's pretty much the accepted way of doing business now. Wherein your fees for storm water are not calculated by your water consumption, but rather by your runoff. So, you will have two different parts or your bill now. You all have these if you are DC resident or DCWASA bill payer, effective May of 2009.
So, you pay one portion of your bill based on your consumption which if you're a parking lot owner is nothing. But another portion of your bill based on your runoff which if you are a parking lot owner is significant. Now, this diagram shows the GIS mapping, so Geographic Information Systems mapping which DCWASA uses to determine your perviousness.
All of the areas identified in blue are impervious. So, these is the area they're calculating for your bill. Now, as a commercial building owner you could get it with some pretty significant bills down the line. But it's still fairly small because these are benchmark in the ER use and equivalent residential unit which is a 1,000 square feet.
Now to make it easy and also because there's very little financial benefit for the city ones you calculate the man hours. Every home dwellings or single family home attached or detached is judged as one ERU regardless of their lot size. And you would think, "Oh, but my lot is much smaller and I don't want to be built unfairly." Except that these calculates out to $26.40 a year. It's nothing. It's an entirely negligible fee.
It has absolutely no impact on the amount of money that it's going to take for us to remediate our very pressing pollution and storm water issues. So, when you calculate all these out across the city, across all building types, across all square footage, these fee generates $6.9 million a year.
Now, remember I told you that $2.2 billion was the number that was going to cost us to build these tunnel. It would take 318 years for us to pay for that tunnel if we were to continue paying fees at these rate. So, I'm sure that you all can imagine the escalation that's going to take place in these fees over the next 10 years.
Now, when we look at the federal government landscape this is I think some of the most compelling numbers. There's a very low return on investment if you're looking at just all sitting here at pervious surface fees. But when you combined them with things like the extended roof life, and the reduced seeding and cooling cost and the increased value of the amenity on your building.
Now, you're really starting to talk about dollars that you can calculate in your building value and in your rentable dollars per square foot value. And the federal government owns 7% of the building stock in DC or 7% of the pervious building or impervious building surfaces. So, there are 260 million square feet of building footprints in DC of that the federal government is almost 18.5 million.
That means that every year not including parking lots and other vacant lands, the federal government pays $485,000 in impervious surface fees. So, as this escalates you can see that the federal government would be paying millions of dollars of impervious surface fees which is still a drop in the bucket for the federal government. And again since we're in storm water I can make these jokes, but they probably spent more than that on toilets last year, so it's fine.
Now, here's what we would like them to do. Let's start talking about what they've been doing and what we really want them to do. Basically they have two main manuals that are going around the federal government that are sort of the bar of fore facility managers. So, the first is greening federal facilities.
This is a 2001 addition, it has not been revised since 2001. While it had the most cutting edge landscaping techniques at that time and it does use language like, we would like you to consider, and we think these are good. It doesn't specifically say wherever possible you should use these techniques. And it doesn't use any stronger language the type that we would like to see.
GSA also in 2008 just released sustainability matters which is a very beautiful profile of all of the different case studies of green buildings that the GSA has participated in. These is available as a very, very large pdf, but as a free pdf online. If you just Google GSA Sustainability Matters.
Now, again I think it's a really great step in the right direction, but what we do want to see is a more comprehensive and stronger language about storm water management practices because it does not specifically say the facilities managers or maintenance managers should consider as high as priorities any of the landscaping forms that we'd like to see on both the ground and on the roof.
So, the other thing that I wanted to bring up again just very briefly is the lead silver designation that's being applied to many federal facilities as well as the DC Green Building Act which does not go far enough to meet our comprehensive storm water remediation goals. So, we would like to see aside from just needs over standards something being called out more.
And I get to concretely which is actually the furthest thing we want to be in front, but we want to see something called out more concretely saying what we're willing to do to acknowledge significant storm water issues aside from any lead ratings.
Now here are some examples of how the federal building decisions can impact us -everything around us. So, for example job creation in these market would include suppliers and manufacturers of green roofing materials, gardens, and nurseries specializing in green roof plants. It would also include jobs for design and engineering professionals which I have a feeling many of you in the audience are. So, yehey for you.
Also, jobs for contractors and landscapers. And especially green collar job training. So, for example, they saw the entry level jobs that I was talking about earlier. This is a fundamental shift from working at McDonalds to working on a green roof. And I know that that makes a town like a very, very wide spectrum, but there are many shades of green in between.
And if we can start to move our job base along it would be pretty beneficial for us. So, the number here from Germany is saying that their industry in place approximately 12,000 people in green roofs. And if December were to increase so if all the roofs are green it would be 100,000 people.
I know you're saying, 'well once we green on the roofs how is it going to continue to include those people. Well, you do need men on some of these roofs and you do need people to take care of the plants and it is a different industry than just having tar up down on your roof. So, we are fundamentally going to be shifting the way that we spend capital on our buildings.
But as you can imagine I think these 12,000 people in Germany who work in green roofing are probably fulfilled with their jobs. I think they understand the societal benefits of it. I think going to work outside on a daily basis is attractive to many of us. It's a very different type of job from the traditional gray infrastructure core base.
Now, there are many community cost savings that can result from this. So, we would like to talk specifically I think about increased storm water retention and decreasing it to expand or rebuild related infrastructure. These goes back to the $2.2 billion level again.
So, these pipeline is currently under construction. There is not much we can do to change that, but if we change the way that we build new communities and if we change the way that we remodel or rebuild the communities that we're in now. There's the potential to save money by building less of these gray infrastructure.
You also see decreased cost of meeting green house gas reduction goals in adapting to climate change. So, for example interior building inflation is a very, very important thing. And I would never say that the green roof substitutes interior building inflation. But we want every building to have the tight assembler possible and the most inflation possible.
Now, there are a number of different ways that you can combine green roofs with your roof insulation and we think that those provide a ton of benefits, but the one thing that just insulating and not green roofing. Can't say is that it reduces the urban heat island effect which ultimately reduces the need for your home to heat and cool itself. And there's also a decreased need for healthcare services.
Now, this is highly debatable, but based on implementation of just all green infrastructure in general. You will see increased quality in air quality and water quality. So, reduction in ground level ozone from the reduction of urban heat island effect equals a reduction in asthma, a reduction in allergies, reduction in pollutants in urban environment, it's a very simple equation.
Now the amount to which this happens and the extent to which you realized health benefits is very dependent obviously on the amount that you implement these techniques in the prior state. Additionally, you can't continue to have buses spewing fumes everywhere the way that they have been and say that we're going to improve ground level air quality.
So, lots of variable imply. Also, of use of green spaces increased in worker productivity and creativity. How many of you have a view of a garden from your office? One. Got one, anybody else? Two, three, four, five. OK. How many of you are jealous of the people who have a view of a garden from their office? There we go.
So, you guys can see the difference I'm sure. I don't need to explain to you what these benefits are as you can realize them. The last couple that we would talk about, again are horticulture therapy now. Horticulture therapy many people when I start talking about these will say, " Oh, that sort of touchy feely and passive experiences with nature and vegetation. I really don't know what that means."
And what can you really tell me about what that does. But, I think for a person whose been called a tree hugger, I may be a little bit sensitive about this. But, it does have an impact on you to have plants around you. And you probably don't know this until you live in an environment where you have only built environment, only gray infrastructure.
And my pretty significant awakening in my entrance into the environmental movement was stimulated by a year spent living in Jakarta where I think there are a sum total of five trees and you could probably count them on two hands. It's really not that big of an exaggeration.
But we would live the city on the weekends and go out to the rainforest and just the change in your overall demeanor and your body is an amazing thing to experience. And in Washington we're fortunate because we do have trees and we do have parks all around us. And so, you're only seeing that in varying degrees.
But if you think of a world without these things. Try to imagine a world with the most that we could have and what the difference between those. So, I think then probably you'll see what we mean by marginal benefits. And we also believe in conserving resources and in recycling. So, there are a lot of different green roofing materials now that are using recycled composite PVC's, plastics, all sorts of things.
So, we think that that is going to have an additional benefit. Currently the state ratably but seven years is the life cycle of a green roof in terms of the carbon footprint total, take you seven years to recover the footprint of installing that roof, but obviously when the project has a life of 50 years, you would say that the life span is far outsetting.
And then the other thing about conserving resources is that if you don't have to re-roof every year. There's a lot of labor that 's saved in that. So, again these is how we're shifting the labor is this labor in stripping roofs and reinstalling roofs and mopping tar or is this labor on tending plants. So, we're just shifting the job base.
Now, the focus we're today was in the National Capital Region and implementation, and all of you are here because you were interested in that. And so, there are several things that you can do now that we'd like for you to do now. Install a green roof is the first one. So many would say, "Where am I going to install a green roof, and these money, and like where am I going to get it?" But, many of you can plant a tree.
So, if I didn't get you on the first bullet point, I'd definitely got you on the second bullet point. So, don't leave here today thinking that you're going to get off scot-free because you don't have a roof.
The next that I would say is volunteer with the storm water group, like DC Greenworks. So, again if you'd like to volunteer, you can talk to Ashley after the lecture today. And she'd be happy to share with you a couple of different things that you can do to volunteer with us.
Other things that you need to do are urge your building to implement LID techniques and support businesses who practice safe water techniques. Let's say, so businesses who reduce water consumption, who reduce water pollution. Businesses who appreciate the environment that they do business in are probably going to be better stewards of your accounts as well. So, we hope that you all take the opportunity to take action on one of these funds and let us know how we can help you if possible. That's all for today.
Sure. We definitely have youth working with us and volunteering with us. So, for example we had a summer youth employment team from the Mayor's green summer job core. There was 48 student this year. We believe we're going to grow the program to over 100 next year. these are people between the ages of 14 and 20.
And these is probably their first experience with environmentalism and they have a component through the DC government where they're doing classroom learning, and they are also working with us in the field for six weeks. So, that's a pretty amazing development
Additionally the DC public school system is making huge strides with advocates in each of the schools developing environmental curriculum. And you will see over the next five years a very aggressive schoolyard greening campaign which I think is going to be pretty innovative in getting kids at a very young age involved in environmentalism and understanding what their consumption of the resources as well.
So, the agricultural component of that I think also is hugely important here. Right. If you're in an older building an extensive system is probably the easiest for you to support it always is. The range of weight of the system is probably the most important because there's another, again I could do another whole hour on planning your green roofing project and what your construction considerations are.
So, you can do it on our website a lot of that as well. but again remember I said that you should talk to my project manager and he's in the backyard too. So, I'll make sure he ambushes you.
Anybody else? You're exactly right it cease and all. So, in the first two years of establishment because you have a lot more open areas, the roofs are more prone to except weeds. So, we typically when we install green roof asked for a two year maintenance package with it and so that would be quarterly maintenance.
That's now after two years you have pretty significant coverage so the maintenance is minimal, but I'm not going to say there's no maintenance. You do want to have somebody up there at least twice a year checking plant health. But again green roofs there are many different types of them as well, so depending on what type you installed, different maintenance requirements.
So, that's just an extensive roof. Obviously if you plant a grove or an intensive roof that's much deeper where you could have trees, and shrubs, and things. It's going to be the same maintenance as a ground level landscaping plan. With an extensive system which is about four inches is what we're typically talking about.
We would say that it captures the first inch of rainwater in a 24 hours storm. So, imagine that telling you that it's going to absorb an inch every 24 hours before it reaches saturation. So, in every additional four inches of growing medium that you add, could absorb an additional inch of rainwater.
Any green roof projects? We just did a really awesome project and that I think Ty would probably love to tell you more about. It was another garage project and these is for a family with young children, and they actually have access to the roof and so they're going to be gardening on their garage roof, very, very cool.
So, now we're finishing I think that was probably our last for the season. We may fit one more in, but we won't do anymore planting this fall. It's sort of a challenge because if your waterproof membranes is really sensitive right? You don't want to poke a hole in it because that means you have water in your building. That's the very simplistic way to look at it.
And that if you can control that, so you for example are aware of your membrane being sensitive, and you are not going to use any like pointed spades on your roof, you're oK. with that. In a public setting, you know, any place where you get in a condominium association or commercial building or things like these.
It's very difficult to govern who is on your roof and who has the training to work on your roof. And one errant hoe struck through the membrane could cause significant damage. And so, that I think is probably the biggest issue that I've heard so far outside of load bearing requirements which are pretty significant the deeper you get with the soil duct.
So, imagine that as you get deeper and deeper you need to add beams, and add beams, but what we found typically like DC historical structures, you can support up to like maybe about eight inches before you're looking at really significant amendments. They're totally cost prohibitive. So, new under pinning, new steel beams shut through the building, things that you would never even consider doing so.
There are struggles there where unless you really have a shell of a building or a new construction opportunity, the depth of the soil can sometimes be a challenge. But, you know, then I think that combined with who's actually using the roof or probably the two biggest barriers. But, I definitely would encourage people to do like this garage installation I just explained.
I think this is an amazing thing. So, you build on your garage, you build it strong enough and now you've all of a sudden got 500 square feet of garden on your rooftop. So, I think that's probably the easiest and cheapest way that you could very quickly get a farm
Gosh, it's difficult to tell. Right. If you think that the extensive system probably maxes out at 35 pounds per square foot saturated, I mean if you would just double that again for every four inches that you go up, that's a safe rule of thumb that will keep you within the right margin. But, additionally if you're going to be gardening on the roof or spending any amount of time on it, you can pretty much bypass any of those considerations of the system because you have to manage for your load.
So, there you really don't want to be anything under a 100 pounds per square foot. Right. So, 35 pounds is the max saturated weight of an extensive system. But, you know, as you go up you're going to increase the max saturated weight, but then you also would add your weight if you're turning it into a recreational or agricultural roof. Historical green roofs. The Hanging Gardens of Babylon.
I mean obviously it's a technique that's been used throughout history, but what's really interesting the Kennedy Center has green roofs. Many people don't think of those as green roofs, because they're so traditional. But there are trees built on an overhang over a major road. That's a green roof.
So, a green roof is a green roof, we'll call it a spade, but never take a spade up on it. So, that's a good rule of thumb. Also the GSA in that book that I mentioned, Sustainability Matters. One of their favorite case study on there is a 35 year old green roof that they totally tout. It's a ground level green roof, it sees a lot of recreation, it's over a parking duct they never had any issue with it.
So, if you have any client saying, "Oh my god, my green roof is going to leak and then what am I going to do?" Be like, all right. The GSA do you know anybody more demanding than them? They have one. They like it, it's 35 years old. Here you go, go check it out. So, that probably helps. I mean, is that the ammunition you're looking for. Anybody else. All right. If there's no more questions, thanks for coming here guys and sharing your lunch hour with us. We really appreciate it.
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