Green Roofs

History

Ancient Roof Gardens

Roof gardens have been around since the beginning of recorded history. Man has always had a fascination with having a garden where it was not meant to be, on a high structure. It has been said that being amongst a garden and looking over the city is the ultimate experience.

The Ziggurat of Nannalocated in Ur (Copyright- The British Museum)

The first roof gardens were reported to be located on the infamous Ziggurats of Mesopotamia. The dates span from the fourth Millennium to 600 B.C. Trees planted on terraces helped create a cooler microclimate in the hot desert region. Perhaps the most famous of all rooftop gardens, the Hanging Gardens of Babylon, built by Nebuchadrezzar II (605-562 B.C.), were at one time considered one of the seven wonders of the world. It has been told that Nebuchadrezzar's wife, Amytis, missed her homeland where lush greenery was present so he built her gardens on the roofs of his palace. No factual records exist proving the existence of the gardens, only writing in ancient books, the first in Babyloniaka, some 200 years after the gardens were supposedly destroyed. Stone was used as the building material with the soil being supported by vaulted ceilings. The drainage material was constructed out of a layer of reed set in thick tar covered by two courses of baked clay brick bonded by cement. This was covered by a layer of lead which acted as a waterproof membrane.

(Theodore Osmundson)

A section drawing of the Hanging Gardens of Babylon based on a description by Robert Koldewey

(Theodore Osmundson)

The Romans also created rooftop gardens, as seen by the Villa of Mysteries in Pompeii. The eruption of Mount Vesuvius preserved what was a large residence in Pompeii where terraces were planted with trees and shrubs. Careful excavation and restoration techniques has led researchers to identify some of the plant material used in the garden.

Gardens of the Middle Ages and Renaissance

(Theodore Osmundson)

Italy has always been popular for its historical gardens and included in their history are various rooftop gardens. The Palazzo Piccolomini, The Tower of the Guinigis, and The Medicci Roof Garden are all examples of early Italian gardens where terraces and gardens were placed on the roofs of a building. These gardens preserved views into the country side and urban areas and retained the geometric forms often seen in Italian garden architecture. The Mont-Saint-Michel in France houses a roof garden atop the cloister.

(Theodore Osmundson)

Gardens at Mont-Saint Michel were placed where ever open space was available. The cloister garden rests on the chamber located below.

(travel.webshots.com)

The small Guinigi rooftop garden is located atop a tower in Lucca, Italy. It is accessible by a stairway inside. It features oaks growing in 2-foot-high planting beds.

Roof Gardens from 1600 -1875

(Theodore Osmundson)

Roof gardens dominated buildings in Germany and Russia from the 1600's to 1875. Two of the largest roof gardens were at the Kremlin and the Hermitage. Each had an abundance of trees and shrubbery which hung over walls and provided interior gardens. They used lead sheets for waterproofing. Formal parterres and garden spaces at the Hermitage accentuate the outdoor space and make the art museum an indoor/outdoor experience. The engineers and architects of the time took great care and precision with their gardens as proved by their ability to last over time.

(Theodore Osmundson)

The Hermitage roof garden was designed by the Italian architect Bartolemo Francesco Rasrelli for Russian czarina Catherine II.

A look into the formal parterre are the hermitage located in Saint Petersburg.

(Theodore Osmundson)

(Erik Christensen)

(Theodore Osmundson)

Germans and Norwegians were amoung the first to discover using plant material on the roof as insulation. This decreased temperature extremes allowing inhabitants to spend less energy and time on heating and cooling the house. Grass and flowers grown on the roof were used only in a functional sense but proved to be ornamental as well. In the center image you can see the cribwork that holds the sod on the most distant building.

Sod houses like these were common in Germany and Norway during the 19th century. Each tree has taken root in the roof in the picture above. In the bottom picture to the left, the roof was formed by covering a layer of saplings with overlapping shingles of sod.

This garden is located on top of The American Theater in New York City. (Museum of the City of New York, The Byron Collection)

Theater roof gardens in the United States between 1900 and WWII were popular, allowing plays and public entertainment to be held outside on hot summer nights. Large seating areas and stages were placed on the rooftop. Plant material consisted of small trees, shrubs, and flowers planted at the edges of the building in containers or small beds. After seeing these expansive and accommodating gardens on top of many New York theaters, New York Hotels and apartment residents caught the roof garden fever and created their own. The features on these roof gardens consisted of Italian pergolas, Venetian arbors, wisteria groves, and flowering alleys. Lighting was abundant so users could enjoy the space in the cool summer evenings.

Gardens Built Prior to WWII

Union Square was recently rebuilt to accommodate modern Sa Francisco. Built in the early 1940's it led the revolution of underground parking garage ground-level rooftop plazas in the United States. (Theodore Osmundson)

Several gardens built before WWII were pioneers in the roof garden industry and have led to the construction of many of those seen in urban areas today. Union Square in San Francisco is a at grade city plaza located on top of a parking garage. It is in the center f the downtown shopping district and enjoyed by thousands each day. It serves as an early example of parking garage rooftops. Those to follow it were Mellon Square in Pittsburgh, the Kaiser Center in Oakland, and many others.

Modern and ECO-Roof Gardens

Lightweight materials made the Kaiser Resources garden a possibility. (Theodore Osmundson)

Modern gardens like the Kaiser Resources roof garden in Vancouver B.C. use technologically lightweight materials for roof structure and planting material. Advancements in roof structure load bearing capacity has led to to the possibility of numerous landscape materials that were considered too heavy in the past. In the past hundred years the ECO-Roof garden, one that consists of grasses and groundcovers and is usually pedestrian limiting, has been implemented in Europe to make up for lost green space taken up by construction. The primary purpose for this type of garden is added insulation, addressing ecological issues, and improving views from nearby office windows. Recently, the United States has adopted and implemented ECO-Roofs in an effort to decrease urban temperature and reclaim lost green space. Stormwater issues are also dealt with by the retention of rainwater that would otherwise be flushed into the sewer system.

(Theodore Osmundson)

This ECO-Rooftop garden in Stuttgart, Germany replaces the space taken up by the building footprint with green space.

Stormwater is decreased as the plant material holds rainwater for a longer period of time than would a flat concrete roof.

Ancient Roof Gardens Roof gardens have been around since the beginning of recorded history. Man has always had a fascination with having a garden where it was not meant to be, on a high structure. It has been said that being amongst a garden and looking over the city is the ultimate experience.
The Ziggurat of Nannalocated in Ur (Copyright- The British Museum)	The first roof gardens were reported to be located on the infamous Ziggurats of Mesopotamia. The dates span from the fourth Millennium to 600 B.C. Trees planted on terraces helped create a cooler microclimate in the hot desert region. Perhaps the most famous of all rooftop gardens, the Hanging Gardens of Babylon, built by Nebuchadrezzar II (605-562 B.C.), were at one time considered one of the seven wonders of the world. It has been told that Nebuchadrezzar's wife, Amytis, missed her homeland where lush greenery was present so he built her gardens on the roofs of his palace. No factual records exist proving the existence of the gardens, only writing in ancient books, the first in Babyloniaka, some 200 years after the gardens were supposedly destroyed. Stone was used as the building material with the soil being supported by vaulted ceilings. The drainage material was constructed out of a layer of reed set in thick tar covered by two courses of baked clay brick bonded by cement. This was covered by a layer of lead which acted as a waterproof membrane.

(Theodore Osmundson)	A section drawing of the Hanging Gardens of Babylon based on a description by Robert Koldewey

(Theodore Osmundson)	The Romans also created rooftop gardens, as seen by the Villa of Mysteries in Pompeii. The eruption of Mount Vesuvius preserved what was a large residence in Pompeii where terraces were planted with trees and shrubs. Careful excavation and restoration techniques has led researchers to identify some of the plant material used in the garden.

Gardens of the Middle Ages and Renaissance
(Theodore Osmundson)	Italy has always been popular for its historical gardens and included in their history are various rooftop gardens. The Palazzo Piccolomini, The Tower of the Guinigis, and The Medicci Roof Garden are all examples of early Italian gardens where terraces and gardens were placed on the roofs of a building. These gardens preserved views into the country side and urban areas and retained the geometric forms often seen in Italian garden architecture. The Mont-Saint-Michel in France houses a roof garden atop the cloister.

(Theodore Osmundson)	Gardens at Mont-Saint Michel were placed where ever open space was available. The cloister garden rests on the chamber located below.

(travel.webshots.com)	The small Guinigi rooftop garden is located atop a tower in Lucca, Italy. It is accessible by a stairway inside. It features oaks growing in 2-foot-high planting beds.

Roof Gardens from 1600 -1875
(Theodore Osmundson)	Roof gardens dominated buildings in Germany and Russia from the 1600's to 1875. Two of the largest roof gardens were at the Kremlin and the Hermitage. Each had an abundance of trees and shrubbery which hung over walls and provided interior gardens. They used lead sheets for waterproofing. Formal parterres and garden spaces at the Hermitage accentuate the outdoor space and make the art museum an indoor/outdoor experience. The engineers and architects of the time took great care and precision with their gardens as proved by their ability to last over time.

(Theodore Osmundson)	The Hermitage roof garden was designed by the Italian architect Bartolemo Francesco Rasrelli for Russian czarina Catherine II. A look into the formal parterre are the hermitage located in Saint Petersburg.

(Theodore Osmundson) (Erik Christensen) (Theodore Osmundson)	Germans and Norwegians were amoung the first to discover using plant material on the roof as insulation. This decreased temperature extremes allowing inhabitants to spend less energy and time on heating and cooling the house. Grass and flowers grown on the roof were used only in a functional sense but proved to be ornamental as well. In the center image you can see the cribwork that holds the sod on the most distant building. Sod houses like these were common in Germany and Norway during the 19th century. Each tree has taken root in the roof in the picture above. In the bottom picture to the left, the roof was formed by covering a layer of saplings with overlapping shingles of sod.



This garden is located on top of The American Theater in New York City. (Museum of the City of New York, The Byron Collection)	Theater roof gardens in the United States between 1900 and WWII were popular, allowing plays and public entertainment to be held outside on hot summer nights. Large seating areas and stages were placed on the rooftop. Plant material consisted of small trees, shrubs, and flowers planted at the edges of the building in containers or small beds. After seeing these expansive and accommodating gardens on top of many New York theaters, New York Hotels and apartment residents caught the roof garden fever and created their own. The features on these roof gardens consisted of Italian pergolas, Venetian arbors, wisteria groves, and flowering alleys. Lighting was abundant so users could enjoy the space in the cool summer evenings.

Gardens Built Prior to WWII
Union Square was recently rebuilt to accommodate modern Sa Francisco. Built in the early 1940's it led the revolution of underground parking garage ground-level rooftop plazas in the United States. (Theodore Osmundson)	Several gardens built before WWII were pioneers in the roof garden industry and have led to the construction of many of those seen in urban areas today. Union Square in San Francisco is a at grade city plaza located on top of a parking garage. It is in the center f the downtown shopping district and enjoyed by thousands each day. It serves as an early example of parking garage rooftops. Those to follow it were Mellon Square in Pittsburgh, the Kaiser Center in Oakland, and many others.

Modern and ECO-Roof Gardens
Lightweight materials made the Kaiser Resources garden a possibility. (Theodore Osmundson)	Modern gardens like the Kaiser Resources roof garden in Vancouver B.C. use technologically lightweight materials for roof structure and planting material. Advancements in roof structure load bearing capacity has led to to the possibility of numerous landscape materials that were considered too heavy in the past. In the past hundred years the ECO-Roof garden, one that consists of grasses and groundcovers and is usually pedestrian limiting, has been implemented in Europe to make up for lost green space taken up by construction. The primary purpose for this type of garden is added insulation, addressing ecological issues, and improving views from nearby office windows. Recently, the United States has adopted and implemented ECO-Roofs in an effort to decrease urban temperature and reclaim lost green space. Stormwater issues are also dealt with by the retention of rainwater that would otherwise be flushed into the sewer system.

(Theodore Osmundson)	This ECO-Rooftop garden in Stuttgart, Germany replaces the space taken up by the building footprint with green space. Stormwater is decreased as the plant material holds rainwater for a longer period of time than would a flat concrete roof.