# Tower In The Park - a design problem, or a demographics problem?



## Zach759 (May 20, 2010)

If I'd want to be around greenery I'd live in a house not a tower. It just seems silly.


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## Time69 (Mar 9, 2008)

memph said:


> I also have no idea how the average was calculated since the average sky view factor I get for the courtyard is either 0.48 or 0.51, not 0.57, so it seems like their effectiveness is exaggerated. The courtyard model also seems to assume you don't need to make any room for streets and that the bottom of the building can't be used. A lot of highrises will have a large podiums with uses that don't require natural sunlight as much such as offices, retail, parking garages, gyms, etc. Natural sunlight is also not the only thing that matters, windows can still let light in even if the sun doesn't shine directly through them, and people might be willing trade natural sunlight for a better location. There is just no way you can have FSIs of 15+ with lowrises like you can with some highrises in New York, Hong Kong, Toronto, etc.


I agree it is a bit of a disapointment that only tables and no curves per floor number is provided in this paper, and quite astonishing that no more precise work with full light simulation done on this aspect.

However, the bottom line is that for each shape and generic pattern, the density (in FSI term) is asymptotic (I did some simple formulas like March on Maple, unfortunately lost the file, but typically up from 10 floors you almost don't gain anything), and this is primarily due to the fact that when you make a building higher, you cannot make it thicker, and especially true for housing : you can make an office tower much thicker than an housing tower (big open plans with elevators, coffee machines, meeting rooms in the center, open space around), except if you put really huge flats, housing building limited to around 12 14 meters thickness.

Also true that the courtyard model presented doesn't include streets/roads.

But for FAR/FSI computed at the city or city block level including streets (half streets area around taken into account for a block), I don't think even in New York or Hong Kong you go up to 15, much less in fact. Read somewhere (cannot find link back) that the densest place in terms of FSI is the chicago ring with a value of around 7. And in fact if you look at latest housing high rise in HK they are more like high rise slabs than towers.

The point is that for a given FSI, if you compare a "towers pattern" and a "slabs pattern", the slab pattern (with less storeys for the given FSI) will lead to better natural lighting in the flats.

Bottom line is that this is a bit "counter intuitive", and can also "piss people off", breaking the "higher is better and is the future" mantra (interesting for instance that March mentions in his paper an architect from Singapore that got pushed to some "cheap work" for having said it).

And for instance the average FAR of central Paris (with "haussmanian" buildings or courtyards blocks 6 to 8 storeys high) is 3.5 (and up to 5.5) when the "la defense" one is around 2, and the one of the "seventies housing developments"(with slabs and towers) in France is around 0.7 !!

Taken from below doc :
http://www.fnau.org/file/news/HabitatFormesUrbaines.pdf
(summary tables pages 20 & 21)

Note : in fact really not that easy at all to find these numbers (and also need clear definitions, like counting common areas or not in the buildings, etc), would be interested to have some in NYC, HK, etc.
And also not to forget that the latitude is important in this domain : at lower latitude you most probably can go to higher FSI with same lighting level in the flats.

As to the greenery aspect, for me clearly the park is the good approach, that is, not "green in between buildings due to necessary spacing", but which is just a green area (like central park typically, or London or Paris ones)
(and on appartment terraces, buildings roofs)


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## memph (Dec 11, 2010)

Time69 said:


> I agree it is a bit of a disapointment that only tables and no curves per floor number is provided in this paper, and quite astonishing that no more precise work with full light simulation done on this aspect.
> 
> However, the bottom line is that for each shape and generic pattern, the density (in FSI term) is asymptotic (I did some simple formulas like March on Maple, unfortunately lost the file, but typically up from 10 floors you almost don't gain anything), and this is primarily due to the fact that when you make a building higher, you cannot make it thicker, and especially true for housing : you can make an office tower much thicker than an housing tower (big open plans with elevators, coffee machines, meeting rooms in the center, open space around), except if you put really huge flats, housing building limited to around 12 14 meters thickness.
> 
> ...


I was mostly thinking about individual lots when I mentioned the FSI of 15+. Some of the proposals in Toronto are have that kind of density. Theatre Park will have an FSI of 20 and I think Residences at RCMI will be even denser. At this point, we're definitely not talking about tower in the park developments though, but about highrise infill. The FSI for the city blocks those projects are in are definitely lower, I think the densest city blocks in Toronto are around an FSI of 10. However, much of the buildings surrounding Theatre Park are of historical value. You might be able to get a higher density at the city block level if you destroy all the buildings and build Haussman style courtyard midrises, but that's not an option. So, you take advantage of the fact that the surrounding buildings are going to stay low-midrise and won't be blocking the view and go highrise and build almost up to the edge of the lot line. 

I agree that for developments where you're buildings an entire neighbourhood from scratch, you can get some pretty damn high density with midrise courtyard buildings, so in most cases skyscrapers (especially residential) are not necessary, but they still make sense as infill in high-demand downtown neighbourhoods. And I think you might still be able to get slightly higher densities with highrises even at the city block level. You can go denser than an FSI of 5.5 with 50 storey point towers (around 10), so in cases like the new neighbourhoods just South of downtown Toronto, or just West (City Place, Fort York), I would say that skyscrapers can make sense too, especially if they have some offices, retail, parking, condo ammenities, etc in the podiums, which might be 3-10 stories and cover much of the city block.

In places like Uptown Oakville, a new "downtown" in the suburb I'm from, a lot of the buildings are planned to be in the 10-20 storey range, but I think the FSI of the densest city block was going to be 2.8. The density is ok, it doesn't have to be super high since it will likely not even get anything beyond rapid bus transit and is way out in the suburbs, but I think narrow streets and midrises with a higher coverage might have been better.


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## Time69 (Mar 9, 2008)

memph said:


> I think the densest city blocks in Toronto are around an FSI of 10.


I seriously doubt that, a FSI of 10 is huge, might be true for a lot within a block of course, but not for a complete city block, and even less if we compare FSI at city level, so that for a block you should include half the street area surrounding it in the denominator.

Would you have a google map link for this or these blocks ?

By the way, the FSI advised as reference design by "carfree cities" is 1.5 :
http://www.carfree.com/far.html


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## memph (Dec 11, 2010)

Time69 said:


> I seriously doubt that, a FSI of 10 is huge, might be true for a lot within a block of course, but not for a complete city block, and even less if we compare FSI at city level, so that for a block you should include half the street area surrounding it in the denominator.
> 
> Would you have a google map link for this or these blocks ?
> 
> ...


Maple Leaf Square is a 1,250,000 sqft mixed use complex, and even if you extend it to the middle of the streets surrounding it, it still has an FSI of about 9 (my estimate from google maps).
http://maps.google.com/maps?saddr=B...-kqmAXy9IEy9eg6ypzgYPw&cbp=12,76.84,,0,-32.34

Source for square footage:
http://urbantoronto.ca/database/projects/maple-leaf-square
http://www.lanterradevelopments.com/our_communities/maple_leaf_square.php

Wikipedia cites 1,800,000 square feet, but I suspect that includes the office tower across the street.

Across from York Street, there's a parking lot. It's between bremner, the Gardiner, York and Grand Trunk but not including the section South of Grand Trunk. The address is 16 York and the proposal is about 1,810,000 square feet and would include a large (I think 31 stories) office tower and condo towers of 57 and 67 stories. Based on a google maps estimate of the site area plus the land up to the middle of the surrounding streets, that's an FSI of about 11.

The Simcoe Place/CBC block has a high FSI too, it includes:
1,554,000 square foot CBC broadcasting centre (1)
1,215,000 square foot RBC Centre (office tower) (2)
700,000 square foot Ritz Carlton Toronto (condo-hotel) (3)
750,000 square foot Simcoe Place (office tower) (4)

1. http://www.cbc.radio-canada.ca/facilities/toronto/index.shtml
2. http://skyscraperpage.com/cities/?buildingID=41072
3. http://skyscraperpage.com/cities/?buildingID=36625
4. http://en.wikipedia.org/wiki/Simcoe_Place

The FSI of this block, bound by Simcoe, Front, Wellington and John and including the land up to the middle of the street is about 8.7.
http://maps.google.com/maps?q=Simco...uJq9dgcRAPruMDSg7-VHA&cbp=12,160.88,,0,-39.44

The TD Centre Block is about 4million square feet for an FSI of about 9.1 including the streets.
http://maps.google.com/maps?saddr=Y...xvGfS1guMP1p352T3YB_Q&cbp=12,169.94,,0,-18.92

Across the street, the First Canadian Place block is about 9.8 including the streets.

Just West is what is likely the densest superblock, the one with Scotia Plaza, the FSI is around 12:
http://maps.google.com/maps?saddr=A...BB1PvzjSnJoeDvjPuiOTQ&cbp=12,331.19,,0,-39.64


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## Time69 (Mar 9, 2008)

memph said:


> Maple Leaf Square is a 1,250,000 sqft mixed use complex, and even if you extend it to the middle of the streets surrounding it, it still has an FSI of about 9 (my estimate from google maps).


Using below tool :
http://acme.com/planimeter/

leads to :









So an FSI of 7.9 with 1,250,000

And of course if you take a bigger part of the city around this block you will get a much smaller one. And not sure what is included in the 1,250,000

But my point (or the one of Martin and March), was more that contrary to common belief, tower shapes really aren't that efficient to increase density, and especially true for housing.
For commercial/offices buildings, much "easier" to get high FSI.


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## memph (Dec 11, 2010)

Time69 said:


> Using below tool :
> http://acme.com/planimeter/
> 
> leads to :
> ...


Nice tool, I guess using google maps isn't that precise... And while the surrounding blocks aren't as dense now, they will be. But anyways, the point here is how dense you can go with towers... most cities, especially North American ones have only very small areas that can't be further densified.

By the way, what does that FSI of 5.5 look like? Does it include streets? How tall would those buildings be?

I don't think we disagree too much though. I agree that for most places, you can attain high enough densities with courtyard style buildings, and you seem to agree that office towers district can increase in density with height. I also agree that point towers (esp residential) don't increase density linearly with height. Going from 10 to 50 stories won't increase density by a factor of 5 but probably more like a factor of 2 or maybe even a little less... although it still increases. How about infill type towers, do you think they're a good way to add density in contexts similar to Theatre Park?
http://urbantoronto.ca/database/projects/theatre-park

Also I'm not sure if that many people believe point towers are capable of achieving higher densities than equally tall slabs, winged or courtyard style buildings... I think it's more about taller = denser, and point towers are mostly more popular now compared to slabs for aesthetic reasons.


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## Time69 (Mar 9, 2008)

The block with FSI 5,5 is below one (with half surrounding street area) :

http://maps.google.fr/maps?q=paris&...oid=MhGJH_J4B8Df8xkzpq3rzg&cbp=11,110.57,,0,0

(the block with kind of triangular shape enclosed by Bd Rochechouart, rue de Dunkerque, Rue Guerande.(not really a "top" Paris part))

Otherwise yes I agree you can get quite high density with towers, but with respect to the subject, you really cannot get high density with "towers in the park" whatever the towers height, and for a given FSI towers won't necessarily lead to better lighting in the appartments/condos (except for the top ones), more the contrary.

And again office towers and housing towers are quite different beasts (even if you can do mixed ones depending on floors with top floors having a lower floor area for instance, or huge condos). Or except if it's ok to have quite a lot of rooms without windows (the case for theatre park "moulin rouge" condos type for instance).



memph said:


> Also I'm not sure if that many people believe point towers are capable of achieving higher densities than equally tall slabs, winged or courtyard style buildings... I think it's more about taller = denser, and point towers are mostly more popular now compared to slabs for aesthetic reasons.


The point is more to compare different urbanism type for a given FSI, and for a given FSI a slab or courtyard building urbanism will be much less tall than a "pointing towers" one, so taller=denser, doesn't really hold, in fact what would be nice to have is a kind of 2D diagram, with FSI value on the x axis, max floor numbers on the y axis, and have "typical urbanism" as "point" on the diagram to get an idea of what it leads to. But true that there also are "easthetic" reasons (or cultural ones). Been "playing around" a bit (as a hobby and lost plenty of files in a crash ...) with more slabs like urbanism (or slabs court yard hybrids) to see what it can leads to, and overall quite surprised there isn't more "theoritical" work done on this, especially with current computing tools available (even if in the end, the particularities of a given location are also of course key to any project, but more to get "general ideas" of heigth/urbanism forms/light/FSI relationships).

And btw happy new year to all !


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