Modular Additions to Existing Home, California

Floor Plan
About architects

Architecture Kate Simonen, Phil Kaefer, Benjamin Parco
Area 1,800 square feet
Location Berkeley Hills, California
Year 2009
Photos Caren Alpert

Located in Berkeley Hills, California, the beautiful old house was built more than fifty years ago by Joseph Esherick - famous in San Francisco architect. George Homsey, who worked closely with Joseph Esherick, remembers that the construction of the house has begun for the sake of a single lady - Louise Nixon. She was a conservative nice woman who just wished to have a beautiful house. But, as the eighty-six-year-old architect from the state of California admits, this is not the whole prehistory of this wonderful house in Berkeley Hills.

Homsey looks back to distant times when it was a pick of Joseph's carrier. At that moment his unsophisticated and, at the same time, one-of-a-kind houses were spread throughout the country and everyone knew his name. George also remembers young "headshrinker" Nixon from the Stanford University who was looking for a new house of an Asiatic style somewhere near Berkeley Hills. Designers from Esherick Studio offered her a model of T-shaped house in Japanese style. They also proposed to cover the roof with shingle, which was typical for the Berkeley region. It was supposed to become an attention-getting house near the down slopes of Tilden Park.

The building was finally finished in the middle of 1950's. A fresh face of the Modernist American style, Lawrence Halprin, helped with landscape setting. He showed his vision of the eastern part of the house - meadow with a small runlet and a fascinating impoundment.

Nixon married Louise in 1967 and had been living in that house for nearly fifty years. Unfortunately, they had no children. Nixon died in 2003, and, a year later, his grand-nephew Eric Gimon (a physical scientist, the Energy Department insider and Technical Advisor) with his wife, Emma (Philosophy Doctor of architectural engineering), purchased the house. They faced the only problem - the former house keepers lived there only two together and Gimon's family needed more space in the house as they lived there with a little daughter Louise, two sons and a dog called Nefi. Many people for one old wooden house, isn't it?

So, the family decided to expand the territory of their new home. Emma admitted that they were worried too much about the process. They didn't want to destroy the architectural style of Joseph Esherick. Emma didn't much care about the landscape - she supposed, it was neglected and wasn't finished at all. So, at the beginning of the 2000's they decided to renew the landscape and make it so that it was combined with the overall picture of the house.

Phil Kaefer, Benjamin Parco, Gary Roth and Kate Simonen helped the Gimons to implement their desire. Kate had worked on an idea of prefab additions at the beginning of 2000s. Few years later, she cooperated with architects Parco and Kaefer, creating new modular additions to existing home. And the landscape designer Gary Roth had also joined them. He had been working hand in glove with Lawrence Halprin until he died in the year 2009.

They were discussing a lot of ideas that could allow the family extend their living space. At last, the command decided to remain the original idea of the house and to update the eating area, make a tremendous decking for Gimons to have a rest there. They wanted the family to finish their working day and come home where they, after having dinner in their new maple kitchen, will finally have a rest in their new immense deck which takes much space in the southern part of the common house area.

At first, considering to rebuild their old house as soon as possible, Eric and Emma had faced with one problem - it was too insecure to lift a crane onto the top of the hill. They had decided that question very fast and erected the frame of the modular additions to existing home in a few days. What helped them? Walls were made of prefab panels, and unique butterfly roof, despite its big size, was pointed directly ahead. That let the architect team work with no fear to damage something.

The building team had devised all parts of the modular additions to existing home the way that simplified its installing. They shifted lighting parts into big boxes, that had been placed then and there; moved electrical outlets right onto the floor and installed cordless and program-controlled light switches. Paying attention to the couple's preferences, it was known that the house owners honored environmental conditions they lived at. So, they made a decision to cooperate with the group of architects to build a modular additions to existing home with green components that will let them save their money. Heat pump was installed and electricity is generated with roof-integrated solar array.

From the very beginning of the house rebuilding, there was set a goal to construct it much better than it really had been before. Architects stated that the concept had already grown out of its initial construction and customer preferences. Gary Roth explained that his team hadn't tried to jump off the original design and had been working with finished material, just keeping it up to date.

Beautiful Prefab A-Frame House by Jens Risom, Rhode Island

About Jens Risom

ProjectThe Risom Residence
Area700 square foot
LocationBlock Island, Rhode Island
PhotosFloto + Warner

Jens Risom, a famous furniture designer, has announced himself as a talented architect. Popular magazines were shocked to learn that he built a nice summer house for his family for less than $30 000, because previously they had written that it was impossible. He got in touch with one of the popular newspapers and said that he built such an inexpensive prefab frame house they couldn’t believe.

Jens Risom tells that he has found the triangular prefab framing in catalog and brought it to Rhode Island to construct a prefabricated house there. Eventually, the block-modular building system has become more developed, since the post-war period the reputation of such houses was almost zero. Houses were built quickly and they were of poor quality. Jens Risom has proved that prefabs can be constructed due to new standards with wooden frames, an incredibly high ceiling and more other peculiarities. Having been worked for years as a designer, it was not that hard for Jens to create his home project.

Risom was born in Copenhagen in 1916 in the family of the prosperous architect. He remembers with emotional warmth how he liked to spend his childhood with family in Denmark far from the urban bustle. He admits that his father, being the author of a book about house building, had a great influence on him and was the authority for him. His father often struggled with different situations when he couldn’t drive his project to the end. Jens, wishing to gain full control over his objects, suggested father’s struggles to be enormous. He tells with pleasure that he was always fond of design because architecture is the most elegant art he knows.

After finishing the studies at the Royal Danish Academy of Fine Arts he began to gain experience in architecture, working for the architect E. Kuhn. Back at that time, Jens Risom began to think about designer career in the United States. He stopped his thoughts on modern furniture design. He stayed in Manhattan in search of appropriate conditions to start his own business. His first serious proposal became from Dan Cooper who was creating soft goods, being the reputable and well-known decorator. This proposal was not to the young and ambitious Jens liking, because he did not plan to focus his designer career on textiles. Sometime after that, he was allowed to demonstrate to the public some furniture designed by himself. This greatly increased the authority of Cooper.

Risom’s talent was noticed right from the jump, for the reason that Cooper’s works were being performed in a quiet style for many years. Over a pretty short period of time Jens found his admirers and world designers began to learn about him and come to his shows. Jens has been working with Cooper for a few years and finally he had realized that he had no opportunity to control the whole process. For this reason he had separated from Cooper and became an independent unit in the design world. All the more authority he had acquired helping Hans Knoll to finish and represent society his first collection of furniture.

The fate of the young designer was intervened by the Second World War without remorse. For several years he was serving abroad. After returning back to New York, he decided to continue his career all alone and start his own collection under his name. Jens’s popularity gradually began to move into top gear and by the beginning of the 60’s, people had come in scores to employ to Risom’s designer company.

While living with his family in Connecticut, Jens was looking for the most comfortable place on Block Island to build a summer house to have a rest there. His wife with children preferred to spend summer in their rented apartment on the seaside and far from urban hustle, remembering how they lived in Denmark. Finally, after a couple of years, he found a convenient place for house construction in the North of Block Island. Before he started to build, he had been seeking out modules for his prefab A-frame house. He was looking quite long for the most fitted materials that could cost not too much and weather out wild winds, specific to Block Island’s area. At last, he found a respectful design and construction company in Wayland, Massachusetts. It has fulfilled all Risom’s requirements and wishes – cathedral ceilings, panoramic glass wall to let nature inside, wood surfaces with a soft shade and also 10 feet of extra territory. That’s all coasted him over twenty thousand US dollars. After all of the blocks and house parts had been ordered, he developed a design for the construction of his new home. When everything was thoroughly planned, he took care of the safe order transportation through Rhode Island to Block Island. The base of the house was slightly elevated. But it had been targeted so skillfully that no one would ever guess.

It is well-known that the weather on the island is not so quiet as everyone wants it to be. Block Island is famous for its foggy moments when there is no allusion to fogs but in a short period of time, everything is covered with heavy mist and people cannot even see each other, staying quite close. These circumstances made the home being built five weeks longer than it was expected. Construction of the prefab A-frame house was completed in late spring and at the beginning of the summer Risom's family, finally, settled in a new home. However, they moved there not in a full complement, as daughters have been already living in their own homes.

Only two small floors, but the lower one contains two bedrooms, bathroom and kitchen facilities, a living room and a dining room. Meanwhile, boys territory is on the upper floor. What a magical place to escape from the routine of everyday life! Indeed, from the end of spring and till the end of autumn (those were periods of time when Jens could escape from his work and stay with his wife and sons) Risom's family was spending time providing different kinds of activities - from fishing to bushwalks.

From time to time, prefab A-frame house design was supplemented with new details; old parts were replaced with new, something had to be repaired after years that the family lived there. For instance, a building superintendent, John Spier, had helped to replace old glass parts that were rigidly attached to the wooden frame, to new parts that were not so dangerous as old ones. He admitted that to work with large glass was every time fearfully for him. He explained, that it always existed a risk that the glass would be broken to atoms and hurt him and would even make him bleed. But he knew that the new glass would be safer than the old one. Being 97 years old, Jens with his wife arrived to the Block Island to see their new glass in the frame.

Jens admits that he always worried that his summer house would look too new when he wanted to change something in it. His son Sven wonders, how his father always managed to change something and to make it better than it really was. With a faint smile on his face, he tells that his father, being serious to his creation, is proud that he has made his family happy with their prefab A-frame home. He felt that the inspiration came to him from the natural village lifestyle. Risom remembers that his life in Denmark was different from today's city life but it was so nice.

Prefab Sustainable House with Geothermal System, Long Island, New York

About Bates Masi Architects

ArchitectureBates Masi Architects
LocationLong Island, New York
PhotosTy Cole

Greg and Victoria met on a Montauk beach at first when they were teenagers. After many years they decided to leave Manhattan and to return to Long Island where together they wanted to build a sustainable house. The Hamptons hamlet is a perfect place for children during summer. And when they made a decision to have a dwelling where their family with sons, Lucas and Dylan, could escape from the busy city, they definitely knew where it should be.

Paul Masi of Bates Masi Architects is a Victoria’s brother and they decided to work with him. Masi designed a special house for his sister and for his brother-in-law; the main area of the house has a double-height; kitchen, living room and dining room are located in one space connected with outdoors with a large glass pocket doors. Victoria told that they didn’t want to separate the indoors and outdoors. The project was finished in 2008 after two years of works. The house is environmentally friendly; has a geothermal cooling and heating system and a prefabricated foundation. The family got as a result a beach house with the perfect design.

Passive System for Cooling and Heating

During spring and autumn the space of living room, dining rooms and kitchen can be ventilated naturally as it opens on two sides. In summer the direct sunlight is prevented by an overhang and in winter the house has a lot of light and warmth, because it is time when the sun is low.

There are two layers of aluminum woven-coil drapes outside the south-facing large windows above the living room. Due to drapes the house is kept from the overheating in hot months, but when the weather is cooler they allow the sun to warm the space. The texture and appearance of drapes are similar to fireplace netting; they are produced by Cascade Coil Drapery, an Oregon company, and made of recycled scrap metal. The company also supplies the hearth market.

Geothermal System for Cooling and Heating

The house’s geothermal system is open-loop; this system uses 55-dergee temperature of the groundwater for cooling and heating the house. An exterior condenser was not need, as the needed equipment is in the basement utility room. Masi said that here the salt air corrodes them; so they didn’t want to have the condenser and they wanted use geothermal instead.

There are several types of geothermal systems, to heat and cool house they use the constant temperature of Earth, in winter it is warmer than the open air and in summer it is cooler. What kind to choose and is it necessary to install one, depends on some factors.

In the Pryors’ and in other open-loop systems the pipes draw water from the well into the house, then heat pump extracts heat or transfers excess heat to the water before its return to the ground. And in system, called closed-loop, there is some special solution in the pipes; this solution acts as a heat exchanger in buried under-ground pipes. If there is enough clean water that is supplied to the heat pump, an open-loop system is considered to be much more economical, because there is required less excavation.

A pond-loop system has sub-merged pipes in a water. A horizontal-loop system pipes can be buried six feet in the ground. For not large houses, vertical-loop systems may be suitable, but the price of burying pipes deeper than 400 feet down, is pretty high.

The main advantage of geothermal system is that it is more economical than air-conditioning and gas furnaces systems. And it is much more expensive. Every year the owners can save a lot of money, up to 60 percent. Also the upfront cost can be offset by the tax incentives.

Prefab House Design

The foundation of structure is made of concrete insulated panels, which were produced by Superior Walls of Hudson Valley. They were shipped to the building site, craned and bolted together. There was no need for panels to be waterproofed or coated during building process, as the panels are made of water-resistant, dense concrete mix.

Because of a prefabricated exterior walls could have excessively high price, the architects decided to change their plan. But the panels, produced at Cement Board Fabricators’ factory, were used as the rain screen. The prefabricated panels help the house keep comfort temperature by absorbing and transferring heat through gaps made for ventilation between the siding and panels.

In the house Masi used finishes, which are low in toxic chemicals, such as formaldehyde and benzene, and volatile organic compounds. For painting the interior walls, there was used Benjamin Moore Aura matte paint. Osmo Polyx-Oil was used for sealing the American walnut floors, this finish includes thistle, soybean, and sunflower oils among its components.

Prefab Earth Sheltered Homes by Green Magic Homes

Prefab Earth Sheltered Homes by Green Magic Homes


Have you ever thought about living in a beautiful, comfortable and eco-friendly apartment? What about a "house under the hill"? The construction of such an unusual property is a bold experiment, but it is fully justified. Dreams where you can forget about high maintenance fees may come true! Don’t you believe? Let’s check!

More land for less money

The American company Green Magic Homes can offer you such a unique chance with modest prices – houses, made of high-quality materials and covered with vegetation. For example, a four hundred square foot earth-ship will cost you just about $14,000 US that is approximately $35 US per square foot. The company also proposes cheaper variants – belvederes that will cost a buyer only $25 US for a one square foot area. Though, this is a less viable option because of its open conception. But this variant also can be considered when choosing a suitable home for you.

Possibilities to expand your living space over and over again

The modules of these Prefab Earth Sheltered Homes are made of lightweight and durable material – a composite laminate. It is easier than ever to compile your home because the modules are assembled from prefabricated panels, mounted on a flat surface. And then with the help of a drill they are linked together through special holes on the edges. You will be pleasantly surprised to find out that the modular structure of such houses allows home owners to assemble at first a small house and then successively expand your living space when it is needed. Green Magic Homes assures its clients that such facilities and equipment as sewer system, plumbing and wiring channels as well as air channels can be added at any stage of construction and the external coverage is wholly waterproof.

Why not to plant greenery on the roof?

When all modules are assembled, the walls of your house will be covered up with soil. Sooner, grass or flowers will grow out in that place. But there is also another variant of such houses. Walls and roof are built into the earth at the very beginning, so that there will be no need to cover the house with vegetation.

The well-known company from Florida, Green Magic Homes, offers everyone to feel themselves like hobbits. You need only to purchase there a modular home, resembling a "house under the hill", assemble it and cover up the top layer with soil. This bears not only an aesthetic burden, but also gives you a chance to save your money on utilities costs. Even in colder climates it plays a big role in reducing the cost of Prefab Earth Sheltered Home heating because soil and grass covering gives the excellent heat insulating properties.

Infinite Design Possibilities

Green Magic Homes prefab technology allows you to generate varios spaces ideal for: permanent houses, camps, cabins, offices, hotel rooms, clinics, classrooms, health centers, lounges for meetings, covered parking, deposits, Gazebos, among many others more.