MR. KOJO NNAMDIFrom WAMU 88.5 at American University in Washington, welcome to "The Kojo Nnamdi Show," connecting your neighborhood with the world. We're shaping the city with Roger Lewis. Here's a pop quiz on the Washington skyline. The District of Columbia has a height limit that says no building can be taller than, A, the Washington Monument, B, the Capitol dome, C, the National Cathedral, D, none of the above.

MR. KOJO NNAMDIDespite urban legend, the correct answer is none of the above. The District of Columbia's building height limit involves a formula based on the width of the street on which the building sits, with the maximum height allowed being 130 feet. Congress set that cap in 1910. And in the century since then, residents' desire for a city resembling Paris rather than New York has kept the limit firmly in place, but the low-rise landscape has economic repercussions.

MR. KOJO NNAMDIAnd D.C. Mayor Vincent Gray sparked new discussion recently with his suggestion that modifying the height limit of some areas east of the Anacostia River could attract companies that need more space. Joining me to explore the link between the city's height limit and its economic vitality, Roger Lewis is an architect. He writes the "Shaping the City" column for The Washington Post. He's also professor emeritus of architecture at the University of Maryland College Park. Hi, Roger. How is it going?

MR. ROGER K. LEWISHi. Thank you.

NNAMDIAlso joining us from Phoenix, Arizona, is Chris Leinberger. He's a visiting fellow with the Brookings Institution and a professor of real estate at the University of Michigan. Chris, thank you for joining us.

MR. CHRIS LEINBERGERAlways glad to be on, Kojo.

NNAMDIRoger, urban legend has it that the District of Columbia, with its insistence on low-rise building, is modeled on Paris, which Thomas Jefferson liked so much. How did our cityscape develop?

LEWISWell, there's the long version and the short version. I think that the cap on the height limits really in the 19th century was established, perhaps most powerfully by the fact that it was very difficult to fight fires, commonplace of the 19th century, much above 40 or 50 feet. And there were other considerations. There were no elevators then.

LEWISAnd I think that there were a lot of people that because of the technology available and, if you will, the kinds of building traditions (unintelligible), I think, there was just no impetus to build buildings much taller than four or five stories. So I think you have to move into the 20th century to get on to the full story of how things got higher.

NNAMDIWith one other...

LEWISOne...

NNAMDI...brief stop in the 19th century having to do with the 1894 construction of the Cairo Hotel on Q Street, Northwest.

LEWISRight. And that building, that -- the Cairo Hotel is the catalyst, if you will, for the height limits -- the height restraints that were put on in 1910. The Cairo was built on Q Street, on a street with a lot of row houses that were...

NNAMDIWhere it still reigns majestically.

LEWISExactly. And this building was 160 feet tall, where everything else around it was a third of that height, and everybody looked at that and said, wait a minute, maybe this is not a good idea. And, of course, the -- that included the -- people had to worry about fire. And that was one of the major impetuses, there were others for the Height of Buildings Act in 1910.

NNAMDIOn to the 20th century.

LEWISWell, the 20th century, just to summarize very quickly, the 1910 act and subsequent zoning provisions allowed for buildings that could get as high as 130 feet, depending on the width of the street and where they were located in the area, and also depending on what had already happened, what had already been built. There is one exception. I should point out that on Pennsylvania Avenue, the buildings were permitted to go more than 130 feet.

LEWISWe have the technology, as everyone knows, today in the firefighting and safety provisions, construction technology to build a lot higher. All we have to do is look at other cities. But Washington, I think, because of its traditions and because of very strong sentiments about the character of the city, particularly the historic L'enfant portion of the city, there is great resistance to even considering tweaking the height limits of -- for any reason at all.

NNAMDILet's see if that's changing. You can call us. 800-433-8850. How do you feel about raising the building height limit in certain parts of the District of Columbia? 800-433-8850. Or go to our website, kojoshow.org, and offer your opinion there. Chris Leinberger, the D.C. law basically allows a building to be 20 feet taller than the width of the street and sidewalk it sits on. Is that a common formula?

LEINBERGERNo, it's not. There's very few height limits worldwide, obviously, but there are some. And, by the way, with this discussion, Kojo, nobody is talking about building in what would be considered sacred places, you know, going above the height limit, say, at the Mall...

NNAMDIRight.

LEINBERGER...or that would block views of the major monuments. So I, you know, that's off the table. Nobody has talked about that. So, you know, Pennsylvania Avenue, generally speaking, is safe. The issue is, are there places that we can grow because we're going to need to pick more places for growth. And this is a good problem. That downtown D.C., the downtown demarcated by the White House and the Capitol, the last major project that can be built is under construction as of three months ago.

NNAMDIOne at the old convention center site.

LEINBERGERExactly. And this is all very good news considering where downtown was 15 years ago, when there were, you know, 30, 40, you know, empty parking lots. It was dull, dangerous and boring to go downtown. Now, it's just the opposite. It's a very lively and the best real estate market in the country. So this is all very good news. But, you know, good news, bad news is that the rents are now the highest in the country, more than midtown Manhattan.

LEINBERGERAnd that means that only high-end law firms and finance firms and lobbyists can go downtown. That doesn't employ the most of us. And, as I say, we are almost out of land. And, in fact, in the greater downtown, when you add in NoMa, down by the ballpark, DuPont Circle, the West End, the numbers show that we're going to be out of land, out of building capacity, out of employment capacity in 10 to 15 years. So we have to think about it.

LEINBERGERYou know, where is that growth going to go, because it's been such a great story this last decade, where we're now gaining market share on the suburbs after 60 years of losing market share and jobs and office space to the suburbs. Now, we're gaining it. It'd be a real shame if we went back to the bad old days of the late 20th century.

NNAMDII want to go back for just one more second, though, Roger Lewis, talk about how the height limit impacts the architecture in Washington. Since developers can't build up, they apparently built out as far as possible and take advantage of every inch they're allowed. The result seems to be low, boxy buildings and so-called loft apartments with eight-foot ceilings.

LEWISWell, the apartments built recently, just to make a point about some of the better developments of recent years, some of the apartments that have been built recently actually have more than eight-foot ceilings, which is good. They've gone to nine feet. They're small apartments, unfortunately. In fact, we should come back to this. I know Chris would love to talk about this too. The rental market, for example, right now is unbelievably tight.

LEWISAnd one of the things that tall buildings are quite well suited for is providing housing, providing rental or condominium apartments. Right now...

NNAMDIWe will come back to that.

LEWISBut I think the -- what you hear from the architects is that because of the zoning constraints and the height limit and the sizes of parcels, the block and street pattern sets some of this. A lot of the buildings look sort of the same volumetrically. They're -- as you said, they're boxes. There are some open space requirements, which have produced, of course, courtyards, and many of them are voids in the middle of these buildings.

LEWISThere is, at some -- at one level, if you squinch your eyes and look at a lot of buildings, they're kind of the same. Where the architect has the most leeway is essentially in manipulating the street facades. I'm talking now downtown. This is much less the issue once you get onto sites that are farther away that are adjacent to open spaces where the architects can play with more than one facade.

LEWISBut by and large, the great bulk of the commercial real estate in the area of Washington, about which Chris was talking, the architect has relatively little leeway beyond, again, doing composition on the facade facing the street and to some extent, they can play a little bit with the silhouette against the sky, but not very much, because even there you're limited to heights of penthouses and ornamentation.

NNAMDIYou know, Chris, we contacted the National Capital Planning Commission about the pros and cons of changing the city's height limit. Among other things, the National Capital Planning Commission speaking about the Height Building -- Height of Buildings Act of 1910 says while it's easy to say that the law should be changed and that doing so would solve certain problems, it's not that simple. Any change would have consequences, and currently, buildings are oftentimes not even built to allowable height limits.

NNAMDITherefore, before we do anything that might change that skyline, we should ask ourselves some serious questions. Here are some of the questions the National Capital Planning Commission feels that we should ask. Is it because we're running out of developer space downtown? Is that necessarily a bad thing, especially if the scarcity of developer space downtown may be -- may have led developers to consider building in previously ignored locations such as NoMa or Southwest and may in the future spur development east of the river?

NNAMDIIs it because office rates are so high? As former Vancouver planning director Larry Beasley told the audience last year at an NCPC-hosted event, height changes, unless they are dramatic, are not going to make too much of a difference in the economic performance of Washington. What do you say, Chris?

LEINBERGERI would definitely agree with what they said, that we need to study this. I'm -- some mornings, I wake up 60-40 in favor of raising the height limit in certain locations. Some mornings, I wake up 40-60. And they are certainly right that the height limit has pushed out development into NoMa, into the Southwest Waterfront, down by the ballpark, and that's all very positive. The question is, just how much more land do we have? If it's only 10 to 15 years, which, of course, some projections say is the situation, that that's like tomorrow, that, you know, from a planning point of view, we need more inventory to really attract the development that would then attract the jobs to the District of Columbia.

LEINBERGERAnd so I'm not saying, let's rush out and raise height limits. I'm saying, we've got to study this now and think about it. And there's also something that people have not thought about, and that is, is that the -- is what it's known as the air rights above the height limit are very valuable. And if you take a typical office building, has 20,000 square feet per floor, and at the low end, that's worth 50 bucks a square foot. That translates into a million dollars per floor that is owned by, Kojo, you, Roger and me, the citizens of D.C.

LEINBERGERWe own that. It's not owned by the property owner. And so it, you know, it comes to be, you know, hundreds of millions of dollars. And I think we should just have a discussion. And if we, the people, decide that we don't want that money and we want to keep the height limit, that's democracy at work. But if we look at that decision and say, hey, it's going to cost us $500 million to keep the height limit in NoMa. We might have a different decision if, in fact, that was known, how much money it's costing us, we the people.

NNAMDI800-433-8850 is the number to call. Is there a part of the city where you think taller buildings would be a good idea? Roger, D.C. Mayor Vincent Gray reportedly expressed interest in modifying the height limit east of the Anacostia River in parts of Ward 7 and 8 to allow taller buildings that would attract companies that need more space than lower buildings would allow. How would taller buildings, in your view, impact that part of the city?

LEWISWell, I think we ought to clarify a couple of things to answer that question fully.

NNAMDIYes.

LEWISChanging the height limit in certain areas is, that does not mean suddenly having skyscrapers running around the D.C. area. I mean, I think that there is a kind of immediate negative reaction on the part of many people to any discussion about this because they envision something that, in fact, is not what's being suggested.

NNAMDIAllow me to read this email we got from Jonathan.

LEWISGo ahead. And then we'll continue...

NNAMDI"No, no, no," says Jonathan. "One of the reasons that the District is so much more livable than New York City, where I was born and raised, is precisely because of its comparatively low-rise buildings. It was a primary consideration when we purchased my home in Washington. Where buildings go above the average height, the city becomes very typical, losing its charm and, frankly, becoming a potential terrorist target.

NNAMDIIt reduces home values and cheapens the look of our beautiful city. No, thank you." Underscoring the point you're making, Roger, that when people think of raising the height limits, they think, oh, we're going to skyscrapers.

LEWISYeah, and I -- that's -- I address that almost exactly, that objection in a paragraph in the article I wrote on May 7 in The Post. I'm not gonna read it, but I will summarize it. I mean, I think the -- I think that's part of the problem, is the immediate reaction of a lot of people is that as soon as you talk about height limits, it opens the barn door and all the animals get out. That was Jonathan Yardley's reaction to my first article on this in the 1980s when he countered my article with his.

LEWISLook, the fact is there are areas of the city where adjusting height limit restrictions -- and we should point out that height limits are ultimately arbitrary. You asked that question earlier about the width of the street plus 20 feet. That is an arbitrary formula. Height limits are always a judgment call. And my argument is -- and I think Chris agrees with this -- is that there are places in the city where taller buildings, where instead of a 60-foot limit, it might make sense to go to 80 or 90 feet. We're not talking about 400 feet.

LEWISThere are places where, I think -- if I can put on my urban designer architect head, I think there are places where somewhat taller buildings would actually improve the aesthetic quality of a community. And I think that, for example, in, east of the River, there are sites -- I haven't done the study and I think -- by the way, that is absolutely a prerequisite to doing anything, is a very detailed, not shotgun, but rifle-shot study of the city, which really has to be done by the Office of Planning and NCPC, but -- that would locate places where it would make sense to change the height limit, which might be a change of 10 percent or 15 percent or 30 percent.

LEWISSo I think that that -- I think I'd go along with Gray's recommendation that we ought to be looking at that -- and this was what Chris was saying -- there and a number of other places. There was an -- just one other point. There was an excellent article -- I referred to it in my column -- written in the -- last December by Lydia DePillis in the City Paper. I hope I'm pronouncing her name right. DePillis' article actually addresses a lot of these issues, and I thought it was a very good article on this subject.

LEWISAnd she actually identified a number of areas in the city that, in fact, might very well benefit in all respects from some changes in the height limits without compromising the quality or aesthetic character of Washington, D.C. I just want to add one other thing. I think the L'enfant portion of the city, which is less than half -- far less than half the city's area, the area that Chris was talking about, probably should remain sacrosanct.

LEWISAnd I -- while we might add a couple of stories here or there, I don't think you're gonna see -- I don't think anyone would support adding towers, tall, tall buildings to that part of the city.

NNAMDIGot to take a break. But these are just a few of the areas that Lydia DePillis mentioned in the article Roger mentioned in City Paper: in Northwest along upper parts of Wisconsin, Connecticut and Georgia Avenues, especially near the District Line, in Northeast, Fort Totten and Brooklyn, parts of Rhode Island and New York Avenues, the McMillan sand filtration site, where taller buildings at North Capital and Michigan Avenue would, in her view, yield enough density to justify creating more public parkland.

NNAMDIAnd in Southeast, along Benning Road, Minnesota and Pennsylvania Avenues plus the Congress Heights area near the Homeland Security complex that is under construction. Now you can rush to your phones to tell us what you think about that, 800-433-8850. We have a lot of calls already, so you may just want to send us a tweet, @kojoshow. Go to our website, kojoshow.org, or send email to kojo@wamu.org. I'm Kojo Nnamdi.

NNAMDIWelcome back. We're shaping the city with Roger Lewis. Today, we're discussing D.C. building height limits with Roger Lewis. He writes the "Shaping the City" column for The Washington Post and is professor emeritus of architecture at the University of Maryland College Park. Joining us by telephone from Phoenix is Christopher Leinberger. He's a visiting fellow with the Brookings Institution and a professor of real estate at the University of Michigan.

NNAMDIBefore I go to the telephones, Chris, I'd like you to weigh in on Mayor Gray's proposals that he feels that modifying the height limits in certain parts of the city east of the Anacostia River would be a good thing.

LEINBERGERI think it's a very smart idea that, as I mentioned earlier, that the cause of the scarcity of office space, our prices, our rents are the highest in the country, which really means that when, for instance, Lockheed came to the D.C. region and then, of course, when Hilton brought their headquarters to the D.C. region, they never seriously considered downtown or greater downtown D.C. They are in the suburbs.

LEINBERGERWe should have the ability to compete for those kinds of jobs and the back office space and, you know, look at places. My favorite -- you had talked about different places that it could go -- is the Minnesota Avenue Metro station. Right now, PEPCO has a mothball fleet or a mothball plant there, right on the Anacostia River...

NNAMDIYep.

LEINBERGER...on the east side, and it's got a lot of open space there that is used to store pipes and other outdoor storage, a very inefficient use of Washington, D.C., land. You've got the Minnesota station. You've got the H Street streetcar being built out to it. It could be a tremendous location. And the important thing is, it's close to the Southeast and Northeast, the section of our town that needs the employment so badly.

LEINBERGERAnd so it would open up a whole new market for us as far as employers that could come to town that are not willing to pay 80 bucks a square foot downtown, but could pay 30, 40, 50 bucks a square foot at the Minnesota Avenue Metro station.

NNAMDIRoger, before we go to the phones, an emailer wants to know, "What the heck is NoMa?" It's the area north of Massachusetts Avenue.

LEWISExactly. (laugh)

NNAMDIBut we use it as a kind of short hand so frequently in this broadcast and others, that we sometimes forget that there are people who are unfamiliar with the term. On to David in Washington, D.C. David, you're on the air. Go ahead, please.

DAVIDYeah. I'm just a little skeptical about this idea that we're running out of land. Thirty years ago, much of what we regard as downtown was not really very nice to be around, and there were not many offices there. There's so many parts of Washington that can still be developed. The idea -- really, it just seems to me that the push for it would come from developers 'cause, of course, you can make more money if you have more buildings to rent out.

DAVIDBut, I mean, that is not in and of itself a justification for expanding. And also, this idea that we have $500 million tied up in air rights, that only assumes that when they change it, we start charging more money for higher floors. But there is -- that's not gonna happen. If they zone it for a higher, then it's just gonna be -- that'll be free. We'll give away the air rights. I mean, any...

NNAMDIWell, David, before you go any further, how do you respond...

DAVIDOkay.

NNAMDI...to Mayor Gray's suggestion/argument that taller buildings in Ward 7 and 8 of the city would attract companies that need more space? That does not seem to be "driven" by developers.

DAVIDWell, I would like to see the argument that it's necessary to get taller buildings to attract people. I'm kind of skeptical of that idea. There's so much land available for development that could be very attractive.

NNAMDIHere is Roger Lewis.

LEWISDavid, I have to take issue with you, and I think Chris would agree. I mean, there are -- there's not a whole lot of land. I mean, the point that Chris made at the top of the show is that there's actually relatively little developable land left to be developed. Now, there's -- I mean, maybe you're thinking that there's -- there are lots and lots of neighborhoods and sub-neighborhoods where you might like -- where there are existing buildings, there are existing communities, where one might speculate that, over time, they will be redeveloped, that what's there would be raised and something new will happen.

LEWISBut that fact is that's not -- that isn't in the picture. I mean, I think that most of the developable land in the District has been developed. And I think that was the point Chris was making.

LEINBERGERYes. And, you know, just the rapidity by which downtown has turned around is really the argument. That, if somebody had said 15, 20 years ago that downtown D.C. would be built out in 2012, they would have you committed. Well, it's built out in 2012. Shocking. And so -- and I definitely agree we need a study to understand what is the capacity, what is the carrying capacity of the greater downtown and also other places that employment growth could go, because we just don't know.

LEINBERGERAnd so, rather than using opinions, let's get some facts. But I think that the key issue here is that if there is a shortage and -- oh, oh, oh, and by the way, developers don't like this, property owners don't like this, because they like having a constrained market, which artificially drives up prices. All my developer colleagues tell me, oh, don't talk about that, because my existing buildings might have, you know, might have more competition, and therefore, the prices might fall. So this is not developer-driven.

NNAMDIThank you very much for your call, David. We move on to Jen in Washington, D.C. Jen, you're on the air. Go ahead, please.

JENHi, Kojo. I'm sitting here looking at the satellite map on Google Earth of Washington, D.C. And the area east of the river has more green space than all of the other part of Washington, D.C., combined. And that is an asset on many respects, but particularly on an environmental level. And when you're saying, well, we've got land, we've got to develop it, we've got to develop it, I say, actually, no, and that growth is not necessarily always the answer to these problems.

JENAnd everybody likes to try to, oh, jobs, jobs, jobs when they do this. Well, what are kind of jobs that we're talking about? We're talking about low-skilled, minimum wage, service jobs for hotel and service workers or high-priced jobs for people who are gonna commute in from Maryland.

JENWhy not take that beautiful green space east of the Anacostia River, which people have been working so hard and succeeding to clean up, and make that our treasure, our national park, and also focus on what can be done with green spaces so that people over there can have an urban permaculture-based economy.

JENOf course, that sounds utopian. But if you want to do a study about what's really practical and what we need, those people need food. And they don't need to be getting it from Wal-Mart, unless, I guess, suppose you can surround the Wal-Mart by tall buildings.

NNAMDIWell...

JENI just don't buy it.

NNAMDI...Jen, here is Roger Lewis.

LEWISWell, I think, again, Chris and I probably would agree completely with you that there's a great deal of public parkland, open space, vegetated acreage that should not be touched. And one of the reasons that -- transit-oriented development, for example, you've probably heard that term. One of the reasons that smart growth advocates talk about transit-oriented development and greater density and higher buildings is it allows us to accommodate population that wants to live in a place, for example, people want to live in a city, more people than ever before want to live in a city.

LEWISWe don't want to have them go tear down this forested and vegetated landscape to live there. What would make sense, for example, near a lot of transit stations would be to increase density using, among other things, higher buildings. So I would argue that one of the advantages to raising the height limit in certain places is to, in fact, enable us to preserve more -- assuredly preserve these open spaces that you and I and, I think, most Washingtonians appreciate.

NNAMDII'd like to hear our listeners respond to this. Do you think it's possible to allow taller buildings in some parts of the city, but not in other parts of the city? 800-433-8850 is the number to call. We'll go to, yet, another listener. Here is Ralph in Washington, D.C. Ralph, you're on the air. Go ahead, please. Hi, Ralph, are you there? I don't think Ralph is with us any longer, so...

LEINBERGERKojo, could I talk about the environmental impact?

NNAMDIThis is Chris Leinberger. Please go ahead, Chris.

LEINBERGERYeah, the-- this is new research that's come out over the last five years or so, so, you know, I'm sure not many listeners know about this. But we've come to realize over the last few years -- research at the Urban Land Institute, from various environmental organizations and from Brookings, that high-density living is much more environmentally sustainable than low-density sprawl.

LEINBERGERThat if you move a household from, you know, Montgomery County into the District of Columbia, their energy usage and their greenhouse gas emissions will probably drop between 60 and 80 percent, 60 to 80 percent drop. And the built environment, our buildings and our transportation system, emits and uses over 70 percent of greenhouse gases and, of course, energy.

LEINBERGERSo building higher density is going to be the number one solution of how we're gonna become energy-independent and how we're gonna address climate change. Now, there's, you know, lots of reasons -- there are lots of things we have to do. But the numbers and the research is now in, that if you want to deal with climate change, we're gonna have to live in high density where we unintentionally share our heat with our next-door neighbors and we walk or take transit to get around.

NNAMDIIndeed.

LEINBERGERSo this is a sustainability major environmental kind of issue.

NNAMDIRoger Lewis, you've made the argument that increasing height limits, as Chris was pointing out, is the equivalent to increasing density. You've even described the elevator in a tall building as vertical mass transit.

LEWISYeah, it's...

LEINBERGERWell, it is.

LEWISYeah, yeah. I mean, it's transit.

NNAMDIOn now to Andy in Mount Pleasant in D.C. Andy, you're on the air. Go ahead, please.

ANDYHi. Kojo, this is a fascinating program. I would like to say that I'm agnostic about the idea of increasing the height limits in Southeast. And I live in Northwest. I think I don't understand the economic needs of people in Southeast well enough to say yes or no to what they would want to have happen. I appreciate the idea about the density, being it more environmentally sustainable. I agree with that. I really question this idea that we need development forever.

ANDYIt sounds to me like this is what your guests are saying is we need development forever. We're running out of developable land. And therefore, we need to do something about it. And we need to go up. The idea of smart growth assumes that we have to grow forever. And I guess, as an environmentalist, I think maybe we need to grow for a while, but we're assuming that we have to grow forever. This is a finite planet. This is a finite city. I don't think you can grow forever. And I'm really -- I'm sort of appalled at the assumptions...

NNAMDIWell, are you starting with the premise that there should be a suppression of population growth?

ANDYI think that -- I think population growth has to stop. And I think economic growth has to stop eventually. I think we're on a finite planet...

NNAMDIHere's Chris Leinberger. Chris Leinberger?

LEINBERGERI absolutely agree that population growth is the underlying economic and environmental disaster waiting to happen on this planet. But most recent U.N. projections, just the last few weeks, say that we're gonna be hitting 10 billion people on the planet until we level off and begin to decline. And in the U.S., the projection has called for 100 million people between now and 2040. The question is not should we grow, but we are gonna grow. And then the question becomes, where do we put the growth?

LEINBERGERAnd I'd like to put it in the most environmentally sustainable place as possible, as opposed to letting them carve up more forest land and more farm land out on the fringe. So we are gonna grow, and I really wish we weren't. But I'm not gonna advocate for a one child policy, personally.

NNAMDIThank you very much for your call, Andi. Roger, opponents of any change to the height limit worry that we'd end up with tall buildings next to short buildings and that the short ones would suffer. How do you blend heights without wrecking anyone's view or blocking their light?

LEWISWell, I'm glad you asked that because as a designer, I think that's one of the things that we architects wrestle with all the time, even in areas where the height limit isn't an issue. The relationship -- one of the things that I think talented and concerned architects and urban designers worry about is the relationship between buildings, buildings with each other, buildings with open space, the quality of the streetscape. These are all very critical design issues that have to be carefully studied.

LEWISThey're generally not really addressed by zoning ordinances, in that zoning ordinances address the height limit. One of the things that perhaps some of our listeners have heard about is interest, increasing interest in what are called form-based codes or form-based zoning codes, which much more explicitly address the issues of the interrelationships of buildings to each other and to the streetscape and to public space, et cetera.

LEWISSo I think that's a very important issue. It's something we -- certainly, at the University of Maryland, we've been worrying about it since the school was founded in 1967. All our students graduate knowing that that's one of the -- even if their client doesn't raise that concern, it is their concern. It's their responsibility. So I, again, one would hope that the public sector planners in the City Office of Planning, and CPC, if they were, in fact, to undertake the kind of study that Chris and I are advocating. That would be part of the study.

LEWISIt would, you know, how do you transition from buildings that are 40 feet to buildings that are 140 feet. And if you want to see how bad that can be, go to Houston, Texas, my hometown, where there is no zoning and where, in fact, you can see exactly that situation.

NNAMDIGot to take a short break. When we come back, we'll continue this conversation on D.C. building height limits and whether or not they should be modified in certain parts of the city. All the phone lines are busy, so if you have a question or comment, go to our website kojoshow.org or send email to kojo@wamu.org or a tweet @kojoshow. I'm Kojo Nnamdi.

NNAMDIWelcome back. We're shaping the city with Roger Lewis today discussing height limits in the District of Columbia and whether they should be modified. We're talking with Christopher Leinberger. He is a visiting fellow at the Brookings Institution and a professor of real estate at the University of Michigan. And Roger Lewis writes the "Shaping the City" column for The Washington Post. He's a professor emeritus of architecture at the University of Maryland College Park. A lot of callers like to talk about this, so let's start with Trevor in Bethesda, Md. Trevor, your turn.

TREVORHi. Thank you very much for taking my call. So I have a quick comment before I have a question. My quick comment is that I think it would be very imprudent and very unwise of us to not perform one of -- a very, very, very detailed and very careful examination of where in the city we can increase the building limit because we have space, and it would be very wasteful.

TREVORBut my question is about redevelopment. And I'm wondering, well, I know we spoke about this earlier. What is the problem with redevelopment and why is that not on the plate?

LEINBERGEROh, I think redevelopment is definitely on the plate. And, in fact, it's been taking place so beautifully that, as they say in downtown D.C., we're almost out of land. And, of course, the other thing about redevelopment is that we've got very important historic buildings that we don't want to touch, that they are sacred too. And I'm not talking about, you know, government buildings. I'm talking about just old commercial buildings that you don't want to destroy the historic fabric.

LEINBERGERAnd, of course, you don't want to go into the neighborhoods where there are, you know, late 19th, early 20th century townhouses. So it just limits how much land we have. And, again, that's why we have to study it to figure out really how much land we have, so we're dealing with facts, not just, you know, not just opinions.

LEWISTrevor, what -- I would add that there is a lot of micro redevelopment that goes on. There's a lot of -- many projects every year are essentially owners or developers picking up a property, a small property or single building and redeveloping that or even raising it and building something new. That's going to happen continually. Cities -- that's in the nature of city building and city evolution, that there is site-by-site property redevelopment.

LEWISBut the kind of redevelopment that used to occur, I think that's history, I think for the reasons Chris points out, historic preservation forces and other considerations.

NNAMDIAnd, Trevor, so you do think that there can be some modifications of the height limits?

TREVORI think it's limited, but I definitely think that like...

NNAMDIBecause...

TREVOR...was mentioned, there needs to be a serious study about it.

NNAMDIBecause I wanted to talk about specific areas after, of course, a serious study. Roger Lewis, Wisconsin, Connecticut, Georgia Avenues, the upper parts, as the column suggests in the City Paper or the article suggested in the City Paper, especially near the District line, what do you think about that?

LEWISYeah. I mean, I, again, my -- this is very much sort of windshield survey stuff. But I've spent a lot of decades running around the city, and I think there are areas even closer in, but still outside, beyond boundaries, beyond Florida Avenue, where it would be perfectly appropriate to relax slightly height limits by 10 or 15 or 20 percent. And as you get, of course, farther away from the L'enfant planned city, you not only are not gonna see those buildings.

LEWISI mean, even if you build a building that's 150 feet tall, it will be hardly noticeable. But, again, we're taller buildings. And I'm thinking a lot about housing. I mean, I keep thinking about the fact that there is a tremendous shortage right now of rental housing in the city. And if you're looking for a 2 1/2 or a three-bedroom apartment, forget it. You can't find it. So I think there are -- as I said in my article, I think there are both aesthetic arguments for doing this and real estate and economic arguments for doing this.

LEINBERGERAnd by the way, the issue of the neighbors around high-density development is that they actually win twice. If you draw a firm boundary around the high-density development, say, around the Friendship Heights Metro station and you do not let any high-density growth go into the neighborhoods, and that you manage the unintended consequences like people parking in the neighborhoods during the day, which we can certainly do -- in fact, we do do, then the people that are living around there have the best of two worlds.

LEINBERGERThey can live in suburban splendor and walk to great urbanism. And the research shows that their housing values go up between 40 and 100 percent per square foot, compared to comparable houses that are not within walking distance. So they benefit personally because their quality of life goes up. But that's not commonly understood, but the research demonstrates that that's what happens.

LEWISAnd it is -- I will say it's understood, Chris, by people who live in Arlington, Va.

LEINBERGERAbsolutely. Arlington gets it. I mean, they are the model. Arlington is -- I use them throughout the nation as the model.

NNAMDIHere is Gary in Washington, D.C. Gary, your turn.

GARYYeah. I recently bought a house in Southeast D.C. in Ward 7. And I would definitely be for a thorough study -- you know, you know, I'm thinking, you know, here we got Ward 7 and 8, guinea pigs, again. Wards 2 or 3 wouldn't be even considering going, you know, putting in the large or higher buildings in their area.

NNAMDIOh, wait a minute. Wait a minute, Gary. That was Mayor Gray who talked about Ward 7 and 8. In the article that was in the Washington City Paper, it talked about -- and I just asked about – Northwest, along upper parts of Wisconsin, Connecticut, that would be Ward 3, Georgia, that would be Ward 4.

GARYOkay. But they're gonna start in 7 and 8.

NNAMDIHow do you know that?

GARYAnd it would be a long time before they would get around to those other wards. Seven and eight would be the guinea pigs. And I have no problem with development, but I've seen what has happened. I used to -- I lived in Reston for, like, four years. And I saw, you know, the huge skyscrapers that they have over there. Now they have destroyed a lot of the quaintness of that city. I'm thinking about the Silver Spring area, where the Discovery Building is now. A lot of those neighborhoods gone. And for...

NNAMDIWell...

GARYTalk about the jobs...

NNAMDIBut, Gary -- Gary. Gary, let me ask this question. On the one hand, you wouldn't want those wards to be guinea pigs for more group homes and the like, would you? So you don't want them to be guinea pigs for those kinds of social endeavors. You don't want them to be guinea pigs for development with higher height limits. What would you like to see happen in those wards so that there can be greater economic viability?

GARYI have -- I said, I have no problem with development. But it has to be done carefully. Well, they said do a thorough study and get significant input from the neighborhoods.

NNAMDIOkay.

GARYThat's all I'm saying.

NNAMDIOkay.

GARYI think that's very fair. And...

NNAMDII think that's fair.

GARY...I think, Kojo, is that growth in D.C., which follows growth patterns throughout the country, goes -- over the last 50 years, it has gone to the favored quarter, the favored 90-degree arc coming out of downtown, and we all know where that is. That's the Northwest.

NNAMDIYep.

GARYIt is the white upper middle income concentration. It's the same thing as in the rest of the metropolitan areas throughout the country. We're beginning to see growth going to the Northeast and into the Southeast. And that is -- you're not seeing that in any other Metro area in the country. And that's to be relished and really encouraged to have the growth go into Ward 7 and Ward 8 because, you know, 20 years ago, you couldn't beg people to go there as far as economic development. Now that's where the market may want to go, so let's encourage it.

NNAMDIThank you very much for your call. Roger, let's talk about residential buildings. What's the demand for apartment buildings, and how would that market respond if the city were to relax the height limit in certain areas? It seems that there's an increasing demand for two, three and four bedroom apartments in the city.

LEWISWell, we, yeah. When we've talked and written about that. The census, 2010 census has shown, among other things, great demographic shifts, ethnographic shifts. We know -- and Chris probably has the data on this much better than I do -- but we now know that there is increasing interest in a large part of the real estate market. This gets back to the growth discussion. And living in urban situations.

LEWISPeople that have empty nesters, people whose kids are grown and the dog just died want to move back to places where they can walk and not always have to drive and mow the lawn and worry about painting the shutters. There are a lot of younger people who are leaving places like Reston and Columbia because they want to live in a city. So what we are seeing -- certainly in Washington, and I think this is true of many other cities which have a lot of amenities to offer, is a kind of growth, which is really in-migration of people who are specifically choosing to live in urban situations.

LEWISAnd you couple that with the economic situation right now, financial market situation. There's great desire on the part of a lot of people to want to rent rather than buy something. So I think what that's meant is that very tight rental market. From what I've read, there -- the vacancy rate in rental apartments right now is practically zero. And one of the things that you can build quite readily and even make affordable is apartment buildings that will house the people that want to live in the city and not necessarily continue moving out into the edge cities or the sprawling suburbs.

LEWISSo I think -- Washington, in fact, as I recollect, has started on the growth curve upward after years and years of decline. It's not by the hundreds of thousands, but Washington has turned around.

NNAMDIChris, are there certain building heights that make sense economically?

LEINBERGERThere are certain breakpoints as you go up, as far as the infrastructure of the building and, of course, particularly, elevators. And so if you go up, you know, seven, eight, nine stories, you've got one cost per square foot. If you go up to 10, 12, you've got a higher cost per square foot and you don't get much for it. So, yes, there are just practical realities of the construction of these buildings that really necessitate you considering going up, you know, higher than seven, eight stories, if you're gonna bother going up higher at all.

LEWISYeah. Let me be specific on that. Under the -- under codes, under building codes, at 75 feet, when you're over 75 feet in height, the building -- a building is considered a high-rise. That's actually a term of art. So one of the things that a lot of projects developers do is they try and keep below 75 feet. Once you're over 75 feet, you're into high-rise construction under building codes, and that does mandate another level of infrastructure and construction quality.

NNAMDILet's go to Ab in Southeast Washington. Ab Jordan (sp?), we only got about a minute left. Go ahead, please.

AB JORDANYeah. Just two things. I'm a member of a church that owns five acres in Southeast of Ward 8. So, you know, in terms of studying this question, we would love to see it. I mean, we would love on our property to go up, you know, to have more expansion. But the question, Kojo, is when you lay that issue about economic benefit and what have you -- one of the callers who just called, he said there's greater economic benefit -- the problem is, we haven't seen that accrue to all of the people in the District of Columbia.

AB JORDANAnd so that's where the issue is. I mean, yes, we've grown, but the people like me who've lived all their life in the District of Columbia, who've grown up here, we're not the ones who benefit from that...

NNAMDIAnd Ab has been an activist and political candidate in the city for the last 45 years or so. You want to make sure the benefit is spread around, Roger Lewis.

LEWISYes. Well, I think Ward 7 and 8 are certainly places that need to be looked at for this.

NNAMDIAnd I'm afraid that's...

LEINBERGERAnd, by the way, churches are just perfect because a lot of churches downtown have really had their bacon saved, financially, by having redevelopment take place on their church property, on their church parking lot, and it has allowed them to stay and renovate their church and really be much more engaged.

NNAMDIWe're running out of -- Christopher Leinberger, thank you so much for joining us.

LEINBERGERThank you.

LEWISThanks, Chris.

NNAMDIRoger, always -- Roger Lewis, thank you so much for joining us.

LEWISYou're very welcome.

NNAMDIYou can guarantee that if there are hearings about this in Southwest Washington, Ab Jordan Jr. will be on hand. Thank you all for listening. I'm Kojo Nnamdi.