Variation of modes of use: functions, users, schedules, etc.

Relationship between the ownership and the form of the investment that allows the transformation

Variation of the overall dimensions of the building

Proportional relationship between new spaces and existing spaces

Relationship between the structural adjustments and the existing structure

Relationship between the forms and types of pre-existing materials and those of the new intervention

Relationship between the image of the new and the image of the existing (mimesis / contrast)


Case study in via Sant'Anna, Corticella, Bologna. Prototype could be located in different location, stand-alone or as addition to existing buildings


DUETERZI (E. Cattani, M. Ruggieri) - LABORATORIO DI ARCHITETTURA (R. Casarini, A. Rinaldi)



77 DUETERZI – Domani: a new housing prototype for building renovation through volumetric addition.

PROJECT - Main Infos

PROJECT: 77 DUETERZI – Domani: a new housing prototype for building renovation through volumetric addition.

LOCATION: Case study in via Sant'Anna, Corticella, Bologna. Prototype could be located in different location, stand-alone or as addition to existing buildings

YEAR: 2018

ARCHITECT / FIRM: DUETERZI (E. Cattani, M. Ruggieri) - LABORATORIO DI ARCHITETTURA (R. Casarini, A. Rinaldi)

BUYER: Manni Group

SURFACE: 50 sqm

PRICE: € 100.000

The actual investment gap in the renovation sector is due to the fact that high investments are required up-front, generally characterized by a high degree of risk and long payback times. The design team looks at the residential building stock and develops a renovation strategy based upon Add-ons, intended as one (or a set of) volumetric additions – like aside or façade addictions, rooftop extensions or even an entire new building construction - that increase the real estate value of the existing buildings through a significant energy and architectural transformation. "Domani" is the name that has been given to the first volumetric addition produce in Italy and here presented, in Italian it means "Tomorrow" since it has been conceived to be the housing of tomorrow, the densification module that could help our cities in the renovation process and support the transformation towards more sustainable built environments. "Domani" is not a design but rather a design strategy, it is not the arrival but the starting point, it is a suggestion to all those architects that are looking at the existing buildings as 'structures' and grids upon which transformation will and has to occur to move towards the future, towards Domani.

WHAT - Program

PREVALENT REPLACEMENT / DISCONTINUITY: The functional program is predominantly a new program.

The possibility of intervening in the existing city with the addition of incremental portions, today defined as volumetric additions, opens up new scenarios where architecture and economy meet: new ideas are needed to think of lightweight, modular, removable, transportable, flexible constructions, that are added with discretion to the territory built to redesign the urban landscape, paying attention to the resources. The prototype here presented has been conceived to be used as rooftop extention but can also be applied as façade or side extention. On the chosen case study building located in Bologna, the design has been used to test the possible result of a full building transformation through add-ons as presented in the section cover here.

WHO - Financing

TOTAL CONSERVATION / CONTINUITY: The investor is the property owner.

Financing has been supported by a consortium of partners: Costruire Leggero - Manni Group Porcelanosa, Krion Schueco Alpac Eubiq Vanoncini Artemide LaCividina Fantoni

HOW MUCH - Absolute Dimensions


PREVALENT CONSERVATION / CONTINUITY: The overall dimensions increase moderately with respect to the pre-existing surface.


PREVALENT REPLACEMENT / DISCONTINUITY: The overall dimensions are about three times the pre- existing volume.

The prototype has been designed to modules of 1.80 x 4.50 ml with a reduced height of 2.40 ml to increase the density of the city (every ten floors yield one more), built entirely in the factory, taken to the construction site with trucks, raised at a height with cranes and assembled together with magnetic connections. The external contact points are sealed for air tightness with neoprene profiles, while inside they house the Eubiq® electrified tracks for portable management of electric current. The plant module contains all the facilities in the house: sanitary, water, drain, controlled mechanical ventilation, infrared radiant panel heating powered by the integrated photovoltaic system on the roof. Modularity allows different variations of shape and size (S, M, L, XL), which can adapt to different places and meet different needs.

HOW MUCH - Relative Dimensions

PREVALENT REPLACEMENT / DISCONTINUITY: The new spaces are prevalent with respect to the pre-existing spaces.

Conceived as an image of the future, "Tomorrow" is characterized by a pure shape, with rounded corners that enhance continuity and compactness, a large white metal tube on the outside and entirely made of wood inside, interrupted only by the shape and position of the patio green: patio and home are inseparable elements of a new way of living in balance with the earth. Two large high-efficiency windows delimit the living area composed of a unitary space, where there are no functional subdivisions, but informally usable equipment and furnishings: in each point different activities can take place. A long horizontal plane follows the space longitudinally and contains all the equipment, the bathroom is designed as a glass wardrobe to be accessed for individual activities, while the wardrobe is a set of hangers distributed in space, there are no electrical outlets or switches fixed in favor of the idea of current portability thanks to electrified profiles: a different idea of space that anticipates the changes of the future. Built with light dry layered technologies that can be easily assembled and disassembled, "Domani" is not a static object, but designed according to the flow of air, water, light, sound, energy, raw materials and people.

HOW - Design Strategy STRUCTURE

TOTAL REPLACEMENT / DISCONTINUITY: The original supporting structure has been completely replaced by a new structure.

The supporting structure is made with steel technologies (steel frames), the new frontier of light constructions capable of high resistance with limited use of material and only 75 mm wide, resting on the static consolidation structure of the underlying building.

HOW - Design Strategy MATERIAL

TOTAL REPLACEMENT / DISCONTINUITY: The materials chosen for the new intervention are completely different from the pre-existing ones.

"Domani"'s composition layers will have different durations over time. The structure is the most long-lived, then the external casing, then the internal cladding, then the systems, then the furnishings: each one at the end of his life cycle can be converted or reused in an idea of a circular economic cycle that minimizes the waste production.The insulation is made internally with Actis® heat-reflecting thin insulators, and externally in 120 mm thick polyester panels obtained from the reconversion of plastic waste, until a casing with U = 0.107 W / mqK is obtained. Externally the ventilated façade is covered with white-colored thermal-curved Krion® slabs: capable of very high solar reflection and UV resistance, with high antibacterial properties, and photocatalytic capacity with the possibility of purifying, for each housing unit, the air that about 1000 people breathe in a year. Ore obtained from aluminum oxide, Krion® is completely reusable upon its disposal. Internally a double slab of Aquapanel® with a high thermal capacity, coupled with a larch wood surface for a total of 50 mm, forms a thermoregulating mass spread over the entire surface, effective for internal storage. The triple-glazed windows with integrated decentralized VMC system close the entire enclosure The winter climate behavior is guaranteed by the high insulation of the casing (12 kW / mqa) optimized by the thermoregulatory behavior of the diffused internal mass: the integrated infrared panel heating system completes its operation. summer climate behavior, on the other hand, works on the reflection of the heat of the white shell in Krion®, the shielding with external solar curtains of the large windows and on the accumulation behavior of the internal mass, in addition to natural night ventilation, and when this is not possible , to the free-cooling operation of the VMC.

HOW - Design Strategy IMAGE

TOTAL CONSERVATION / CONTINUITY: The new intervention is in total mimetic continuity with the existing structures.

By combining the deep retrofitting with the new construction of Add-on, we made a first step towards circular renovation models. This means, looking at the existing buildings as products that can be adapted, reconstructed and deconstructed to extend their life cycle; densification policies such as this, are the counterforce to contrast urban sprawl since our cities will have to adapt rather than expand. Case studies throughout Europe have proven that this approach is capable of overcoming the actual barriers by establishing an empowering synergy between the old (existing building) and the new (Add-on), in functional, architectural but especially in economic and real estate terms. Now it is our turn, finally also in Italy, we are making a step forward towards Volumetric Additions.