Subtraction - when Architecture gets exposed by elisa.paneni

S U B T R A C T I O N

W h e n

A r c h i t e c t u r e

g e t s

e x p o s e d 1

Technical Studies 3 Elisa Paneni Experimental 15 City/Hall

Introducing Unit brief

Ts brief

Observing Site analysis

Islington Borough Islington Town Hall

Project proposal

Understanding

Steel frame structure

24 40

Materials Elements ConnectionS Exterior Wall Floor Foundations Construction process

Islington Town Hall Subtractive intervention on an existing listed building

Existing structure

Theories on restoration : Viollet-le-Duc & Ruskin

Interventions on existing buildings

Subtraction : Herzog & De Meuron, Caixa forum Subtraction : Heatherwick, Zeitz MOCAA

Facade retention and temporary support

Section

Gordon Matta Clark, Splitting

Cutting Richard Wilson, Turning the place over Steel Bricks Concrete

Proposing

Core cut

Anatomy of the cut Elements Strategies

Peripheral cuts

110

Anatomy of the cut Elements Strategies

Programs

114

Introducing

Unit project introduction

he partecipation into local political dynamics has represented, throughout the centuries, the main way for fostering a sense of collective identity and community. The local authorities functioned simultaneously as servicesâ&#x20AC;&#x2122; providers, ensuring wellbeing, wealth and pride to their people but, also as promoters for debate in a common space where diversity and sameness are tied together. However, nowadays, the local authorities have been deprived of their original role and identified merely as burocratic institutions with a limited power of action. They have become obsolete administrative bodies in which people do not identify themselves, leading to a dramatic process of separation. This divorce from the local political sphere has triggered a reconciliation with the national one which, instead of enhancing a sense of community, amplifies a profound sense of alienation and isolation in individuals. This widely detected lack of engagement into local politics has been the starting point of my research. Tailoring the mentioned above double-role had by local authorities, I will be using the services provided by the council as magnets for the people, stimulating a productive friction between public programs and political functions. By bringing the people right into the hearth of the political decision-making-process, a feeling of mutual engagement will be triggered enhancing a more active public participation into the local community life. The Town Hall building was the symbol of local authorities, being historically located at the centre of cities and considered as a reference point for the community. In current times, it may be rather defined as a mere office building : obsolete, empty and rigid. My project aims at re-qualifying the institution of the Town Hall that no longer would be functioning as an administrative space for burocracy but, it would rather be transformed into a multidimensional public space in which exchange, debate and connection will be the key factors. Starting from a general critique and a defined manifesto for the future of the local political institution, my project research looks at the real life conditions of the Islington Borough. The densest local authority in the whole country which perfectly depicts the decay into which the civicness of local communities has fallen into. A strong and buzzing commercial urban axis and entirely residential peripheral areas characterize this borough that has completely forgotten how to create spaces for interaction and debate. The inefficient way in which the Islington Town Hall is currently used offers an opportunity to re-think how the space is organized and the programs take place within its walls so, to create a civic space for the community. The ambition of my project is to solve with a singular and resolute action of subtraction the depicted situation.

When

Architecture

gets

Technical Studies intentions

exposed

In order to achieve the ultimate goal of re-qualifying the local institution of the Town Hall, a singular and resolute action of subtraction will be carried out. The Islington Town Hall will be radically divided into two halves in order to open up its structure to the public audience, revealing and exposing its intrinsic dynamics. A linear central void will be carved out from the existing volume becoming a multi-dimensional civic space and, thus, re-creating the plaza, that usually seats right next to these political institutions, within the Town Hall building itself. The aim of the Technical Studies final project is to further explore and develop the phases of cutting, adapting and exposing of the project. The cutting phase is concretely analyzed in order to understand how an existing building can be radically modified and split in two parts. The action of cutting through the existing structure is the main move of the project and it is conducted carelessly without compromising with the functions and services encountered by the line of section. All the political activities will be revealed in order to eliminate that aura of mystery that has worsened the separation between the community and the local institution. The adapting phase focuses on the adaptation process required by the existing structure in order to properly perform the new added functions. Indeed, the existing structure does not undergo passively this process of programsâ&#x20AC;&#x2122; contamination but, it rather enriches itself and flexibly accommodates the changes. This phase is crucial in order to further emphasize how the intervention, although it proposes a radical modification of the existing building, is characterized by a sensitive approach for the re-using process. The latter phase focuses on the action of exposing. It does not simply refer to the exposure of political daily activities to the public audience but, also the architecture and structural system will be revealed as never before. The walls, floors and ceilingsâ&#x20AC;&#x2122; build up systems will be exposed showing the damages of the age as well as the marks left from the cutting but, at the same time, giving back a complex and diverse output. Finally, in order to achieve the main intentions of the Technical Studies project, the research proceeds from a phase of Observing, where the context, the site and the goal of the project are presented and analyzed, followed by a phase of Understanding that through the analysis of several study cases and construction techniques provides the tools needed for an aware development of the final proposal.

Observing

Site analysis

Observing Islington Borough

Site analysis

Islington Borough

Archway

Holloway

Angel

The London Borough of Islington is one of the Inner Boroughs of the Greater London Area and it is located in the North-East side of the territory. The Borough was formed in 1965, when the former boroughs of Islington and Finsbury merged together. The territorial entity is the smallest borough of the GLA area and the third smallest local district in the whole country. However, the Islington Borough, despite its territorial dimensions, has a significant population of 240.000 people, giving back a density of 16.140 people / km2. Therefore, Islington is the densest local district, not only in the GLA area but, also in the United Kingdom territory.

The Islington Borough is characterized by a very slender shape, stretching through the zones 1,2 and 3 of the London Travel Fare Zones (TFL zones). This characteristic gives back a great variety of social and economic contexts tied together under the same administrative authority. The southern part of the Borough is part of the Central London area and London congesting zone, therefore in the last decade it has been characterized by several re-qualification projects, being transformed from a mainly residential zone into a buzzing commercial zone. The rest of the Borough is ,mainly, residential, while the main services and commercial activities are located on the Islington High Street, which takes the name of Holloway Road in the northern section and Upper Street in the southern part. This strong urban axis is at the same time a local high street but, also, one of the most efficient London traffic arteries, connecting the A1 highway to the gates of the City of London. The street goes across the three centers of activity of the Borough - Archway, Holloway and Angelidentified as town centers.

Observing

Site analysis

Observing Islington Town Hall

The administrative headquarters of the Islington administration are both located on Upper Street, in a position of centrality for the whole Borough. The offices open to the public are located in the Islington Customer Centre, where matters regarding planning applications, licensing and other main consultational services are offered. On the other hand, the adjacent Islington Town Hall hosts more representative functions, such as concil and commitee meetings. The Islington Town Hall is a listed building built during the 1920s, commissioned by the Islington Council and designed by Edward Charles Phillip Monson. The building was erected in order to replace the former Vestry Hall, located between Upper Street and Florence Street. The construction progressed in three different phases: starting in 1922 with the construction of the rear wing facing Richmond Grove; proceeding then in 1925 with the neoclassical norther extension facing Upper Street, which gave a more monumental entrance to the Town Hall. And, finally, 1929 a further extension was realized, addind to the Town Hall complex the Assembly Hall wing, which has been functioning as event venue.

Site analysis

Islington Town Hall

Ever since its construction the Islington Town Hall has been recognized as the symbol of the Borough, representing the economical growth and the prosperity of the area. It has been the background of all the challenges and events that made the history of the Borough and its people. It is one of the most popular venues for weddings, and, today it is remembered to be the first venue that hosted a same-sex marriage in the UK territory. When the Arsenal Football club won the championship many reception ceremonies were held in the Town Hall and the building has been the background and silent witness of the celebrations. When the Occupy movement was re-claiming the public spaces back in the 80â&#x20AC;&#x2122;s, Upper Street has been one of the main location for the events. It is clear that the Town Hall building is very dear in the public imagery and is a necessary symbol of the identity of the Borough.

Observing

Site analysis

Observing Islington Town Hall

Archive

Archive 240m2

Works’ gallery

Works’ gallery 370m2

Museum of Islington

Museum of Islington 455m2

Assembly Hall

Offices basement

Offices basement 1170m2

Offices ground floor

Offices ground floor 880m2

Offices first floor

Offices first floor 600m2 Mayor’s parlour 80m2

Offices second floor

Offices second floor 1000m2

Committee rooms

Commitee room no.1 150m2 Commitee room no.2 145m2

Council Chamber

Council Chamber 250m2

The tables above show a more detailed comparison between the existing and proposed Islington Town Hall. The programs currently carried out in the existing Islington Town Hall highlight how the building is mainly closed to the public and used almost exclusively by the council officers. However the proposal overview refuses the division between public and private, since the political dynamics are going to be fully exposed and publically visible. New cultural programs would contaminate the Town Hall building functioning as magnets, creating a productive friction that will get the people closer to the decision making process of the council.

1. Council Chamber 2. Committee room 3. Committee room 4.Committee room 5. Committee room 6. Committee room 7. Mayor’s Parlour 8. Assembly Hall 19

Observing

Site analysis

Observing Islington Town Hall

Site analysis

Islington Town Hall

Office spaces

TURNING POINT The Islington Town Hall is a building which is dear in the public imagery of the Islingtonâ&#x20AC;&#x2122;s inhabitants. However, the building is mainly occupied by obsolete and traditional office spaces, and un-used meeting rooms. At the moment the building has a main council chamber and 5 additional committee rooms for a total floor surface of more of 500 m2 of meeting spaces .However, only an average of 14 meetings/month take place in the building and most of them are held in committe rooms no.4 and no.1 while the other rooms are usually rented out to local companies for their meetings (which is not a proper council function). The average duration for each meeting is 3.5 hours, which means that the actual representative functions of the council take place in the building for only 50 hours/month, despite it being open from Monday to Friday from 9 am to 5 pm (160 hours). Furthermore, although the council meetings are completely open to the public (no registration required, walk-in allowed), the public attendance is very low. Interviews carried out with several inhabitants of the Borough have highlighted a general lack of engagement with the local politics and uncertainty in the dynamics of the decision-making process of the council. The building is clearly identified as the Town Hall and, as an important symbol however the functions carried out in its spaces are completely ignored and not known. The main activity that seems to bring people inside the Town Hall Complex is participating to the events which take place inside the Assembly Hall. However, mostly often, the participants do not realize the adjacency with the hearth of the local politics of the Borough. Meeting rooms

Assembly Hall

Observing Project proposal

Islington Town Hall

Observing Project proposal

Islington Town Hall

POLITICS

CULTURE

Volume

Section axis

PEOPLE

Existing elevation

Subtraction

Proposal elevation

Visibility friction

The two main programs present in the existing asset of the Islington Town Hall, other than being in the same building complex, are completely separate from each other. This led to a separation between their users, in fact the proper Town Hall is rarely visited by the public, while the next door Assembly hall is identified as one of the most popular event venues in London and therefore is constantly buzzing with people. Unifying the access to the Town Hall complex is the first move in order to bring together the political and cultural activities in order to gather together the council workers and the public. The ultimate goal is to create more public engagement into local politics and, therefore, trying to achieve more participation into the decision making process for the borough.

Observing Project proposal

Existing

lightwells

openings

Islington Town Hall

Existing elevation

Observing Project proposal

Islington Town Hall

Proposal elevation

Analysis of the existing building

Infill

The existing Islington Town Hall building is a full block building which main entrance is located on the west side facing Upper Street. Three lightwells give light to the interior spaces.

The first phase of the strategy of intervention would be to infil the existing building with programs, in order to achieve the maximum square floor surface, and, then later on, to define further strategies for ensuring the appropriate light supply.

Observing Project proposal

Islington Town Hall

Observing Project proposal

Islington Town Hall

Programs contamination

Subtraction

The second phase of the strategy of intervention would focus on the contamination of the existing political programs with functions specifically identified as capable of attracting people, in order to requalify the building and diversify the audience.

The last phase of the intervention strategy would aim to achieve the creation of a spatial void by an action of subraction: a central linear space would be carved out from the existing building carelessly, without compromising with the political functions that exist within the building and exposing the dynamics of the local politics to the public.

Observing Project proposal

Islington Town Hall

Core cut The central void would become the necessary core for vertical circulation and accessibility to the different programs but, it would also function as a civic space where informal conversations and exchanges will take place. In a long-limbed and dense borough, interposed between housing crisis and new business developments, the civic sphere has been neglected. A new axis will be intersecting the local high street breaking free from the consolidated existing structure of the borough. 28

Observing Project proposal

Islington Town Hall

The project will explore a materiality clear contrast between the existing and the the adds-on, to clearly state the intention of carrying out a sensitive preservation of the existing buildingâ&#x20AC;&#x2122;s historical value, but also of taking a radical and ambitious next step for the future of a local political institution which seems to have fallen into decay.

Observing Project proposal

Islington Town Hall

Y C

L O

T S

E L

Y C

L O

E L

T S

Islington Town Hall

Existing ground floor plan of Islington Town Hall

OPEN WELL

Proposal ground floor plan of Islington Town Hall

Observing Project proposal

Islington Town Hall

Section BB’

Section AA’

West elevation

Section DD’

South elevation

Section CC’ As showed in the sections the action of subtraction and hollowing of the central core allows for a possibility of exposing the existing political functions and creating a visual functional friction with the newly added cultural programs. The odd adjacencies will trigger a machanism of mutual engagement bringing the people and local politics together. The central core will be programless, becoming a civic space of connection, interaction and observation where informal exchanges of informations and ideas can take place. The intervention will take away a portion of the traditional building and give it back to the people. 32

Understanding

Structure

Understanding Steel frame

The steel frame system is a building technique which uses vertical steel columns and horizontal I-beams, which support walls, floors and roofs connected to the steel strucutre. The steel frame structural systerms has been developed only after 1855, when the production of the steel became more affordable and, therefore, could be produced in great quantity through the Bessemer process. Steel started to be considered reliable thanks to its tensile and compressive strenghts qualities, to the point that in 1890 the Rand McNally building in Chicago was the first building to be entirely built with the steel frame system. Among the great qualities that make steel very reliable in the construction field there are : its ability to behave positively both in traction and compression, it allows a greater tension value compared to other traditional materials, it has the ability to cover longer lights and it is very ductile. However structural steel is very vulnerable to the atmospheric agents and therefore needs constant protection. Steel properties : Density : 78.5 kN/m3 Tensile strenght : 275-460 N/mm2 yield stress and 430-550 N/mm2 ultimate strenght Poissonâ&#x20AC;&#x2122;s ratio : 0.3 Modulus of Elasticity (E) : 205 kN/mm2 Modulus of Rigidity, (G) : 80 kN/mm2 Linear coefficient of thermal expansion : 12x10 -6/Â°C

Steel bars with a full cross section are not widely used in Architecture construction, given their excessive weight and extremely high cost and wasteful use of material. They are mostly used in product design industries and to realize equipment and machines.

Steel frame

a b

Structure

x b

Steel profiles can also be hollow in the inside, taking the name of HSS- Hollow structural section.They can also be called steel tubes or box section. The hollow cross section can have different shapes from circular to square and rectangular, while the thichness of the steel is uniform across the whole section. Depending on the shape of the cross section the proper abbreviations are CHS (circular), SHS (square), RHS (rectangular). While the circular and square sections are characterized by having the same mechanical properties on both axis given their symmetrical geometry and therefore they are mostly used for columns, the RHS can have very different dimensions and being used for different purposes.

x t

t b

The I-beam is a steel element characterized by an I shape. The horizontal elements are called flanges while the vertical element is called web. The web resists to the shear forces, while the flanges respond to the bending moment experienced by the structural element. The I-beam shape is very efficient in responding both to shear forces and to bending moment, however it is definitely weaker in carrying torsion. The I beams can be rolled, when formed by hot rolling or cold rolling steel or plate girder if the elements are welded together.

The H beams or, also called wide-flanges beams, are very similar to I beams, with the only difference that the flanges are wider, the difference can be highlighted as web to flanges ratio. Moreover, usually, the H-beams have a thicker web and they weight more, therefore the difference in use between H-beams and I-beams depends of the forces that the structural element will be supporting.

Understanding

Structure

Understanding Steel frame

ne Pin

Structure

d c o n n e ctio

Steel frame

PRODUCED BY AN AUTODESK STUDENT VERSION PRODUCED BY AN AUTODESK STUDENT VERSION

c o n n e ct ion Fixed

The difference between a pinned connection and a fixed (moment) connection is the rotation constrain. We assume that a pin connection will not restrain any rotation, thus, there is no end moment while a moment (fixed connection) is able to restrain rotation and taking an end moment. In steel frame structures, they can be both bolted or welded.

Understanding

Structure

Understanding Steel frame

Structure

Steel frame

Typical exterior wall detail

.5 0

2 1

5 12 34 5 6

1. Coating layer 2. Cavity, substructure for supporting the facade system : hollow rectangular profile 40x25x2 mm _ 40 mm 3. OSB panel _ 18mm 4. High density insulation layer _ 60mm 5. Cavity_ 40 mm 6. Low density insulation layer, C profile steel studs _ 100mm 7. OSB panel _ 12 mm 8. Gypsum Board 40

Understanding

Structure

Understanding

Structure

Steel frame

Typical composite steel floor detail

.5 0

2 1

5 1

1. Corrugated steel deck _ 50 mm 2. Welded steel wire fabric 3. Concrete slab _ 130 mm 4. Floor screed _ 40 mm 5. Floor finishing _ variable 42

6 7 8

6. Low density insulation layer 7. Steel beam, additional fire protection layer 8. Shear stud

Understanding

Structure

Understanding Steel frame

Structure

Steel frame

Typical steel frame foundation detail

.5 0

2 1

5 1

3 4

1. Crushed aggregates layer _ 200 mm 2. Leveling C15 concrete layer _ 100 mm 3. Reinforced concrete footing foundation _ depth and width according to loads 4. Bolted steel plate _ 15 mm 5. Steel column, additional fire protection layer 6. Steel beam, additional fire protection layer 44

Understanding

Structure

Understanding Steel frame

n o f c o n c re

Steel frame

t ns

tio ruc

Structure

tio

ns Pl 2.

ce Pla

m e nt of m a in

ace m ent of co

lu m

jo is t

se con dary b

of nt

Co 5.

n s tr u c ti o n o

Structure

Understanding

Structure

Islington Town Hall

Understanding

1929

1922

1925

Site prior the construction of the Islington Town Hall and Assembly Hall complex, (1920)

Phases of construction Islington town Hall 1922 - Rear wing facing Richmond Grove 1925- Neoclassical northern extension facing Upper Street 1929 - Construction of the Islington Assebly Hall facing Upper treet

Islington Town Hall

Structure

Islington Town Hall

E E R

Structure

Understanding

1925

R E

1929

1922

1929

P O

N M L

10'

I H G F E D

C B

A' B' C' D'

E' F' G' H'

5 4

First phase of construction (1922) _ Ground floor level

Northern extension (1925) _ Ground floor level

Structure

Understanding Islington Town Hall

Structure

Islington Town Hall

Understanding

1929

1922

1925

10'

L" I

B' C'

P O

N M E'

F' G'

H G L"

E" D"

E D

H" G"

C" B" A"

E" D" A

C" B" A"

1" 2"

Assembly Hall (1929) _ Ground floor level

4" 5"

5 4

Overall structural plan _ Ground floor level

Understanding Intervention

Viollet - le - Duc

Viollet-le-Duc was a French architect widely known for restoring many landmarks from the medieval times in France. Among them : the Notre Dame Cathedral and the Cathedral of Saint Denis. His beliefs regarding the intervention and restoration approach can be identified not only by his restored buildings but also by its literary works. In fact Viollet-leDuc defined restoration in his “Dictionnaire raisonné de l’architecture française du XI au XVI siecle” wherehe states that the role of restoration is to re-establish its original state, which it may have never existed but only imagined by the original designer. The process of re-establishment had to follow scientifically defined stages and had to be based on records of the original floor plans and archeological records, as well as on photographs. The restoration had to intervene not only of the appearence of the building but also on the structure of the construction, using more solid materials, and more advanced technologies in order to ensure a longer life of the building.

Understanding Intervention

Ru s k i n

John Ruskin also tailored the concept of restoration but, his beliefs were diametrically opposed to le Duc’s. The opposition between the two architects became crucial in the later thinking which defined the distinction between conservation and restoration. In fact, as Le Duc’s promoted the latter, Rusking firmly believed in the former. “Neither by the public, nor by those who have the care of public monuments, is the true meaning of the word restoration understood. It means the most total destruction which a building can suffer: a destruction out of which no remnants can be gathered: a destruction accompanied with false description of the thing destroyed. Do not let us deceive ourselves in this important matter; it is impossible, as impossible as to raise the dead, to restore anything that has ever been great or beautiful in architecture.” For Ruskin, the “age” of a building was crucially significant as an aspect of its preservation and he could not erase the impact that the time had on existing landmarks.

Observing

Intervention

Observing Subtraction

Intervention

Subtraction

Corten steel extension

Existing brick envelope

Section removed from the existing building

Plaza

Caixa Forum, Herzog & De Meuron, Madrid

Schematic diagram of intervention

The CaixaForum is an art centre designed by Herzog & De Meuron in 2008. The architects intervened on an old power supply factory, located in the city centre of Madrid, in a lively neighborhood defined by many cultural institutes such as Museo del Prado and Reina Sofia Museum. The existing, dated back to 1899, was characterized by classified brick walls which evocked the Madridâ&#x20AC;&#x2122;s industrial age, while the interior was purely functional.

Herzog & De Meuron proposed a surgical intervention on the existing power supply factory, by slicing horizontally the existing construction and subtracting the ground floor level. This allowed for a new spectacular perspective and also solved many issued related to the site. Indeed by subtracting such a huge slice of the construction the architects were able to achieve an open public space and ensure a dignified entrance to the art centre, which otherwise was only served by small secondary and narrow streets. Indeed, by just one singular and sculptural gesture they achieved an extreme and radical result as the building seems to float above the ground level.

Observing

Intervention

Observing Subtraction

Intervention

Subtraction

Existing building volume

Corten steel extension

Subtracted volume

Concrete additional wall

New concrete structure Existing bricks wall

Open plaza Final project volume

Observing

Intervention

Observing Subtraction

Intervention

Subtraction

Phase 1 : Existing building

Phase 2 : Demolition & facade retention

Phase 3 : Construction of new concrete structure

Phase 4 : Insertion of new floor slabs and corten steel facade

Construction site

Construction process The construction phases of the Caixa Forum started by the removal of the ground floor level and of the interior structure. The only part which was left of the existing building was the 4 brick walls which were retained with massive temporary supports. Only once the demolition was completed, the concrete new structure consisting of 3 main concrete cores and one perimetral wall, could be built, together with the new floor slabs. The brick facade was then connected to and supported by the perimetral concrete wall, and the corten steel facade was finally added.

Observing

Intervention

Observing Subtraction

Intervention

Subtraction

Heatherwick, Zeitz MOCAA, Cape Town

Core subtraction

The Zeitz MOCAA Museum was designed by Heatherwick Studio and it is identified as the biggest museum dedicated to Contemporary African Art. It is located in Cape Town, South Africa, and inserted into an old grain silo which once was used to store and grade maize from all over the country. However the huge concrete construction fell into decay with the advent of containerised shipping and remained un-used for many years. The Heatherwick Studio first approached the site with the re-qualification of the water front and then expanded its outreach integrating the old silo into the project, with the constuction of the museum.

The existing maize silo was composed of two parts : a tall tower and a construction of 42 packed silos. The goal of the project was to try to save the identity of the industrial building, avoiding the integral demolition. The studio decided to carve out a big central void between the vertical silos, which would function as the entrance atrium. By subtracting this oval volume from the existing building, all the intersections between the existing geometries are exposed achieving a very suggestive result. The cut silos became tube skylight, thanks to the laminated glass added at the top, ensuring a proper supply of daylight and enhancing even more the atmosphere of the atrium. Heatherwick Studio worked with a very rigid geometry and, by just a singular action, was able to modify completely the perception of the space.

Observing

Intervention

Observing Subtraction

Intervention

Subtraction

Section of proposal project

Floor plan of existing structure

Existing concrete

Goal : Integration beetween the two constructions

Existing shutter finish

Solution: Carved out oval atrium

Polished finish Chamfered edge New reinforced concrete resleeve Jointex Polished finish Dowel connection

Volume

Section plane

Subtraction

Vertical section along cut-line of atrium edge

Understanding Intervention

Subtraction

Phase 1 :

Subtraction

Phase 2 : Construction of the formwork

Definition of the final shape

Phase 4 : First phase of saw cutting

Phase 3 : Pouring of the concrete sleeve

Phase 5 :

Phase 6 : Second phase of saw cutting

Removal of scrap material

Phase 7 :

Phase 8 : Finished result

Edge polishing treatement

Construction site

Construction process Cutting and carving out the vertical silos implied many engineering and architectural complications. Indeed after testing out different techniques the studio had to compromise and change the overall shape carved out from the existing structure. As a matter of fact, cutting the silos with concrete saws only allowed to have linear edges and not round shapes as the original design would suggest. Moreover the existing concrete of the silos was very uneven, given its age, and it had some softer spots and some harder portions, which complicated further more the construction process. In order to achieve structural stability a sleeve of 400mm concrete was poured into the formworks which were already shaped according to the line of cuts. Just after the new concrete was put into place the existing silos could have been cut and then polished with a mirrored finishing.

Understanding

Temporary support

FALSEWORK is defined as any temporary structure used to support the bWWuilt permanent sturcture “until it becomes self-supporting”. Falsework structures are usually made up of timber, steel and aluminium elements. In UK the BS 5975 defines the guidelines for the the correct design and use of falsework temporary structures on the construction sites.

FORMWORK is defined as any temporary structure used to retain the plastic or fluid concrete in its aimed shape until it will harden. The formwork structures are usually supported by falsework systems. Typically formwork structures are made in timber, however they can also be constructed in more expensive materials, such as steel and glass fibre, depending on the aimed result. Formwork structures have to be capable of resisting the pressure of the concrete exerted during the drying process. Once the permanent structure has hardened enough the formwork system can be removed and eventually re-used. SHORING Temporary support structures are a crucial element in the construction phase of both new constructions and rehabilitation of old buildings. Therefore a proper understanding and design of the temporary structures plays a major role in the execution time, cost, safety and efficiency of any construction project. Temporary support structure are defined as “any structure that is used during the construction, rehabilitation and retrofit of buildings”. There are many techniques and systems to ensure the structural stability of a construction while intervening on it, the most common temporary structures are falsework, formwork, scaffolds and shoring systems. All the temporary support structure are used on the construction site for two main reasons : supporting loads and ensuring safety to the workers. As a matter of fact, very often, these structures are designed in order to resist to four times the expected load conditions without experiencing any failure.

is defined as all those horizontal, vertical and inclined elements that support the structure. Shoring systems are usually used to walls undergoing reinforcement, or when adjacent structures are being pulled down, or openings in a wall are made or enlarged. There are different types of shorings depending on the intervention and the element to be supported. Raking shores are inclined members, used to give lateral support to walls. Flying shores are horizontal elements that support two parallel walls. Lastly, dead shores are vertical elements which usually support roofs and floors. SCAFFOLDING is defined as an elevated temporary platform that allows the passage of workers, equipment, and materials. This particular system is not designed for for supporting the structure. It is designed for its self-weight, the horizontal loads (ex.wind) and the loads imposed by the activity that takes place on it.

Understanding

Understanding Facade retention

Facade retention

The first step in designing an efficient facade retention system is to understand the existing structure and how the facade is restrained. In fact the aim of the temporary support structure would be of replicating the existing load path pattern using scaffolding and shoring systems.

The second step would be locking the openings, such as windows and doors, with bracings and reveal tubes. This will not only allow greater stability to the overall facade, but it will become the point to which the temporary support structure will be tied with the existing facade, without needing to cut through the masonry.

Subsequently the whole temporary support structure will be clipped to the existing building. Usually timber elements, such as scaffolding platforms, will be in direct contact with the building, while steel tubes and metal elements that could damage the facade exterior would not be in contact with it. If the facade is retained from the interior of the building, the support structure will be installed through pockets cut in the existing structure, and connected to temporary foundations before the demolition takes place. If the facade is retained from the exterior, the temporary support structure can be placed after the removal of the windows and before the main demolition takes place. However in this case it is crucial to allow pedestrian viability at the ground floor level and permits would be needed in order to occupy the public ground.

Facade retention is a technique that aims at supporting the existing facade of a building when it undergoes renovation, it is often used especially on listed buildings. In fact while supporting with a temporary structure the exterior facade, the interior arrangement of the floor plans can be radically changed, while not altering the exterior look. The retention of the facade is usually obtained through shoring systems, and at the end of the renovation and construction of the internal structure, the existing facade can be attached to it. The temporary structures used in facade retention can be quite massive structures themselves, and have a strong impact on the cost, duration and viability of the overall project. In order to properly design efficient support structures it is vital to understand and analyze the existing building, its structure and its condition. Types of retention usually are : scaffolding, which is mainly used when intervening on 3-4 storeys buildings and sufficient space at the ground floor level for the installation of the temporary structure; proprietary retention which is used for taller buildings as the quantity of components is reduced compared to the scaffolding system; fabricated steel-work which is mainly used when the cost of proprietary equipment outweigh the cost of fabricating a single steel structure.

Wall tie and anchor tie

Window reveal tube

Reveal between columns

As these structures are not only temporary but rarely independents, in order to provide stability it is necessary to clip them to the existing building, as explained at no.3. In the scaffolding sistem there are different kinds of ties that can be used. The through ties are put through windows openings and connected to the scaffolding system through an horizontal beam. The box ties are usually used to attach the scaffolding structure to pillars or comparable elements, creating a box around it. The anchor ties allow the scaffolding structure to be connected to the existing building through drilled holes. The reveal tie is the least invasive, it use an opening in the existing facade and use a tue wedged horizontally in the opening and then connected to the scaffold through an horizontal scaffold tube.

Understanding

Section

Understanding

Section

A section drawing is a representational tool used to show a view of the structure as well as of the interior spaces as if the overall building had been cut along an imaginary plane and then separated. It is considered a useful tool as it gives a a glance of the connections and relationships between the different parts of the building that may not be clear just by an empirical experience of the space. Floor plans can be understood as a section, the only difference with the â&#x20AC;&#x153;section drawingsâ&#x20AC;?, is the orientation of the cutting plane, which instead of being vertically is placed horizontally. Therefore, given these definitions, it becomes clear that the best way not only to represent but also to understand an Architecture is to cut through it. All the parts become exposed to the audience and there is no finishing nor plasterboard to cover up the real essence of the architecture components as well as no shield to hide the activities carried out in the sectioned spaces.

Exposing through cutting By a single and resolute action of cutting through, all the relationships and connections between the parts get exposed and the overall funtioning of an object is immediatly understood.

Understanding

Section

Understanding

Section

Gordon Matta Clark, Splitting, 1974

Real life section

Gordon Matta Clark was an American architect who carried on a critique of the building speculation and of the profession. Splitting (1974) is the complex intervention of Matta-Clark on a traditional house which was slated for demolition. The building purchased by the â&#x20AC;&#x153;art dealerâ&#x20AC;? Holly Solomon became one of the most popular art works of Matta Clark. The artist-architect cut the house into two halves with a chainsaw, he started from the center of the roof and proceeded all the way until the ground level floor slab, without leaving anything behind. With his work, Matta-Clark defied all the rules of statics and gravity, challenging the Architecture and exposing all its parts with a brutal incision.

The result of Gordon Matta Clarkâ&#x20AC;&#x2122;s incision is a real life section, the imaginary plane becomes real and the action of cutting throug is achieved by a chainsaw and not simply by the imagination. The result is an overlaying and adjacency of functions and spaces, and immediately the overall structure of the architecture is understood and displayed.

Understanding

Cutting

Richard Wilson, Turning the place over, Moorfields, 2007-2011

Understanding

Cutting

Three axis rotation

Richard Wilson art work colonised the former Yateâ&#x20AC;&#x2122;s Wine Ldoge in Moorfields from 2007 to 2011. Commissioned by the Liverpool Culture Company when the city of Liverpool was selcted to be the Capital of Culture in 2008. Wilson created a huge 8 meters circular void on the facade of a 5 storey concrete frame building and made it oscillate in three dimensions. The cut out facade was connected to a particular device, a rotator, usually used in the shipping and nuclear industries, which made it rotate along 3 axis. The revolving circle functioned as a window giving constant glimpse of the interior space to the walking visitors, exposing not only the technical details of the facade but also the appearance of the interior spaces.

Understanding

Cutting

columnsâ&#x20AC;&#x2122; line of cut

Y A TES ' S WI N E LO D G E

1. Existing facade

4. Re-construction of the facade

Construction site

Y A TE S ' S WI N E L O D G E

2. Structural frame

4. Cross section _ added structural supports

Construction strategy The construction has been designed mainly in situ, without any drawings to follow other than the main overall idea. Indeed, cutting through all the elements of the facade, structural columns and beams included required an important work of compromises between the design idea and the structural feasibility. The rotating portion of the facade occupies the lenght of 3 floors, therefore the floor slabs of the 3rd and 4th floor where cut in order to allow the rotation of the new facade frame, while the structural columns which were placed in correspondence of the facade were cut from the 3rd floor level to the 5th floor level. In order to build this art work a massive demolition was involved. Indeed a whole portion of the facade was first demolished and later on re-built using lighter materials. In order to structurally support the overall building a secondary structure of vertical shores was placed supporting the 3rd and 4th floor slabs, while at the ground floor level inclined shores had to be placed in order to support the second line of columns which were greatly affected.

Understanding

Fire cutting

Cutting

Understanding Steel

Cutting

Steel

Sawing

Cutting torches

Diamond blades

The process of fire cutting has been widely known with many different names such as flame-cutting and Oxy-fuel cutting. The process uses oxygen and fuel gases to cut but, also, to weld materials. In order to cut materials a cutting torch is usually used; these tools have a concentrator tip that mix the oxygen with fuels and sending the mixture at high pressure through a small nozzle. The fuels can vary from Gasoline, to Hydrogen and Propylene, however the most common is Acetylene The metals are first heated until the flame becomes cherry-red, and once the temperature is reached, the oxygen is added. This will trigger a reaction producing more heat and an oxide which is blasted out of the cut. The torches can reach the temperature of 3300 Â°C, while the melting point of any steel is set at 1530Â°C.

A saw is typically a tool made of a clade or wire characterized by a toothed edge, which is able to cut through different materials if it is moved forcefully on its surface. Sawing is one of the most known techniques for cutting materials, however regular saws and grinders would not be able to cut through structural steel. In order to cut through structural steel diamonds can be applied on the edges of the blades of the saws. In fact diamond is a form of Carbon, and it is defined as one of the hardest substance known. Diamond blades come in different shapes and therefore creating different tools : circular saws which are the most widely used, diamond gand saw, which is made up of a long steel plate with diamonds tips welded into it, and lastly diamond band saw blades which constists of closed steel bands with diamonds electroplanted on it. Grinders are tools powered by either electricity or compressed air and use saw diamond blades for cutting hard and thick materials.

Understanding

Water jet

Pure and abrasive water jet cutting The water jet cutter is a tool that became popular because of its precision and ability of cutting a wide range of materials of different thicknesses. The water jet cutters use a very high-pressure water (30,00090,000 psi) which is run through a high pressure pump and then focused into a beam through a nozzle. Pure water jet cutters usually can cut softer materials from rubber to wood of thicknesses below 150mm, however if the water is mixed up with abrasive additives the cutters can precisely go through harder and thicker materials such as steel and concrete. One of the main advantages of using the water jet technique is that the inherent chemical structure of the cut material is not altered in any way, therefore when cutting a steel beam or column its mechanical properties will not be affected. Moreover the precision of the cut is in the range of 1 to 1.3 mm, allowing for a very limited quantity of scrap material to be produced. The water jet cutting technique has a very recyclabe process, in fact both the water and the abrasive materials can be re-used while at the same time having very few dangerous emissions.

Cutting

Understanding Steel

Cutting

Steel

Plasma cutting Diamond blades

Plasma cutting is a technique used to cut through electrically conductive materials by a beam of hot plasma. Similiarly to flame-cutting methods, the plasma cutting process uses torches characterized by high-speed and preicsion cuts. The process is based on the creation of an electrical channel of highly heated plasma, aimed at the work piece, and then forming an electric circuit back to the plasma torch through a grounding clamp. This flow creates a high amount of heat which is then able to melt down the steel and create the cut.

Understanding

Low tech

Hand saw, drill , hammer, chinsel

There are several low tech tools to cut bricks. Indeed, bricks can resist strong compression forced but they are very easy to cut trough. When removing a whole brick from a brick wall, the only necessary step is to remove the mortar, so the brick will be freed. If it is necessary to remove a portion of a brick, it has to be freed from the mortar first and then the drill and the chinsel will be the necessary tools. A series of holes will be made with the drill along the cut line, and after that with a cold chinsel and a hammer the small dividers between the holes can be broken. Still using the chinsel and moving along the cut line, holding the tool with a slight angle towards the waste side of the brick, the cut will be completed.

Cutting

Understanding Bricks

Cutting

Bricks

High tech

Circular saws As seen with steel and concrete, sawing is one of the most efficient and quick techniques for cutting through materials. As the clay of which bricks are made up of is not such a hard material as steel and concrete, diamond blades will not be necessary. Just a simple masonry blade will do. The important aspect of cutting to softer materials with saws is to remember of not going straight for the full thickness of the material, as it will damage the material surface on both sides of the cut. It is rather necessary to proceed one inch at the time, so to be as precise as possible.

Understanding

Water jet cutting

Understanding

Cutting Concrete

Coring

Pure and abrasive water jet cutting

Circular saws

The water jet cutter is a tool that became popular because of its precision and ability of cutting a wide range of materials of different thicknesses. The water jet cutters use a very high-pressure water (30,00090,000 psi) which is run through a high pressure pump and then focused into a beam through a nozzle. Pure water jet cutters usually can cut softer materials from rubber to wood of thicknesses below 150mm, however if the water is mixed up with abrasive additives the cutters can precisely go through harder and thicker materials such as steel and concrete. One of the main advantages of using the water jet technique is that the inherent chemical structure of the cut material is not altered in any way, therefore when cutting a steel beam or column its mechanical properties will not be affected. Moreover the precision of the cut is in the range of 1 to 1.3 mm, allowing for a very limited quantity of scrap material to be produced. The water jet cutting technique has a very recyclabe process, in fact both the water and the abrasive materials can be re-used while at the same time having very few dangerous emissions. Especially when the cut has to go through concrete slabs and columns the water jet technique is the most efficient, in fact it would not alter the mechanical properties of the material nor damage it, while saws and other mechanical cutters could possibly create damages by making the structure vibrate.

Concrete coring is a cutting process which exploit the same stategy as diamond blade saws. In fact this method uses a diamond cutting drill to cut perfect holes in any concrete component. The process is not invasive at all, as a matter of fact it does not create any dust nor any noise and it is very quick and precise. The holes can be cut at any angle, wheter vertical, horizontal or inclined. One of the great benefits of this technique is the perfect edge of the hole, in fact the material is not damaged at all. This technique is mostly used to create openings for the installation of pipes systems.

Understanding

Fire cutting

Thermal lance The process of fire cutting has been widely knwon with many different names such as flame-cutting and Oxy-fuel cutting. The process uses oxygen and fuel gases to cut. but also to weld, materials. In order to cut concrete structures through the flame cutting technique the most appropriate tool would be the thermal lance. It consists of a “steel tube packed with alloy steel rods”. Oxygen is provided into the tube, while the end of the tube is placed into an holder. When the lance is lit by a torch it creates an intense stream of burning steel that can cut through most materials. During the process the tube gets consumed. The termperatures of operation of the thermal lance can vary up to 4500°C.

Understanding

Cutting Concrete

Sawing

Concrete saw A concrete saw, known also as consaw and slab saw, is a power tool used for cutting concrete, masonry and asphalt and other solid materials. As in the case of the structural steel, nomarl blades would not be able to cut through concrete, therefore the consaw usually use diamond blades. Usually the concrete saw are water cooled, in fact the friction produced by the blade and the hard concrete could break.

Proposing

Core cut

Situation no.2

Situation no.1

10'

A' B' C'

P O

10'

A' B' C'

P O

N M

F' G'

H G L"

E D

H" G"

E" D"

N M

F' G'

H G

Core cut L"

E D

H" G"

E" D" A

C" B" A"

OPEN WELL

1" 2"

4"5"

OPEN WELL

C" B" A"

OPEN WELL

Existing structure overlayed on proposal ground floor plan

1" 2"

4"5"

OPEN WELL

Structural intervention proposal ground floor level

Proposing

Core cut

The Islington Town Hall building was built between the 1922 and 1929, therefore the construction system differs slightly from the modern solutions described in the Understanding chapter. Based on the refurbishments reports which have been carried throughout the years and assumptions based on the â&#x20AC;&#x153;Structural Engineers Pocketbookâ&#x20AC;?, The floor slabs have been identified as clay hollow pot and the exterior walls have been identified as made up of brick blocks placed between steel columns.

Core cut

Situation no.1

Existing structure: Floor plan detail

Intervention : Situation no.1 _ line of cut

14 13 12

11 10 9 8 7 6 5

10 cm

50 cm

Existing structure : Section detail 1

Exterior wall 1. Plaster board _ 12mm 2. Bricks blocks layer _ 120mm 3. Insulation in cavity _50mm 4.Brown bricks facade _ 55mm 96

Ceiling 5. Plaster board _ 12mm 6. Rebar _ variable diameter 7. Clay Hallow pot_ 160 mm 8. Concrete layer _ 40mm

3 4

9. Floor screed _ 40 mm 10. Damp proof memvrabe 11. Floor finishing _ 14mm

Interior wall 12. Plaster board _ 12mm 13. Brick block _120mm 14. Plaster board _ 12mm

The situation no.1 is presenting when the line of cut lies exactly along the structural grid line, and therefore exactly where the vertical supports, columns, are placed. In this situation the floor slab is cut exaclty where the horizontal support, beam, is placed. In this case no additional structural supports will be required as the structure will mantain its stability. After the demolition, in order to add the desidered glass facade, a poper connection to the existing structure will be required. 97

Proposing

Core cut Situation no.1

The main goal of the project is to expose both the everyday activities that take place within the Town Hall spaces but also to expose the existing architectural structure, with all its aesthetic characteristics and layerings. Therefore the glass facade inserted has to ensure this result, for this reason a glass system which uses spider connectors and vertical supports in structural glass has been selected. Indeed, a frame system would be more visually invasive. 5

Phase 1: Demolition

20 cm

Existing structure exposed by the glass facade

0 10

10 cm

50 cm

Phase 2 : Construction 0

Glass wall 1. Fin connecting plate 2. Laminated support in structural glass 3. Spider connector 4.Silicone sealant layer_20mm 5.Double glass layer _ 10+12+10mm 98

1 2

Spider connectors detail

10 cm

4 5

Proposing

Core cut Situation no.2

Core cut

Existing structure : Roof frame

Intervention : Situation no.2 _ line of cut

Line of cut

25 5

10 cm

100

50 cm

250 cm

The situation no.1 is presenting when the line of cut lies randomly in the floor plan, and therefore without any alignment with the existing structural grid. In this situation the floor slab is cut at a random point and therefore there would not be any horizontal beam supporting it. In this case it is necessary to add structural supports, as otherwise the structure will no be stable. The structure will have to be properly propped, with vertical shores, while the demolition takes place. After the demolition, in order to add the desidered glass facade, a poper connection to the existing structure will be required. 100

101

Proposing

Core cut Situation no.2

Situation no.2 : Final proposal Situation no.2 : First proposal

0,5

1,5

25 100

50 cm

250 cm

In order to cut the structure at a random point with no alignment to the existing structural grid. Structural support will be required. Therefore the first proposal focused on inserting a new vertical column exactly where the line of cut lies. However the result of this proposal would be in contrast with the aimed aesthetic goal. In fact As the desired result is to expose the layering of the existing wall and floor structure, inserting a vertical support where the line of cut lies would eliminate such effect.

102

100

The final proposal is focused inserting the vertical support just before the line of cut and then work with screnographic techniques to re-construct the desired wall layering appearance.

103

Proposing

Core cut Situation no.2

Phase 1: Demolition

line of cut

Final proposal _situation no. 2

50 200 cm

0 10 cm

500 cm

Phase 2 : Construction

Glass wall 1. Added Structural vertical support 2. Added Steel beam 3. Fin connecting plate 4. Laminated support in structural glass 5. Spider connector 104

2 3

4 5 67

6.Silicone sealant layer_20mm 7.Double glass layer _ 10+12+10mm

Added support elements 105

Proposing

Peripheral cut

Peripheral cuts

Structural intervention proposal ground floor plan 1'

10'

Existing structure: Floor plan detail Q

A' B' C'

7,00

P O

N M

6,00

F' G'

7,00

H G L"

E D

demolished stairs

H" G"

E" D" A

C" B" A"

OPEN WELL

1" 2"

4"5"

10 cm

50 cm

Location of intervention of peripheral cut 1'

10'

A' B' C'

7,00

P O

N M

6,00

F' G'

7,00

H G L"

E D

demolished stairs

H" G"

Existing structure : Section detail

E" D" A

C" B" A"

OPEN WELL

1" 2"

106

4"5"

OPEN WELL

Interior wall 1. Plaster board _ 12mm 2. Brick block _120mm 3. Plaster board _ 12mm 107

Proposing

Peripheral cuts

Phase 1: Demolition

Line of cut _situation 3

2 5

10 cm

50 cm

Phase 2: Construction

Interior glass wall 1. Aluminium frame 2.Glass layer _ 16mm - 6 mm 12mm 108

109

Proposing

Programs

Light

DANCE • • • • •

Dark

Direct

Diffuse lighting Soundproof room Natural ventilation Dumb equipment Technological finishing

ACTING • • • • •

Open

Ventilation

Forced

Open

Equipment

Tech

Dumb

Finishing

• • • • •

LAB

Diffuse lighting Open sound room Natural ventilation Tech equipment Clean finishing

Clean

Technological

STUDIO

MUSIC

STUDIO

Dark lighting Soundproof room Natural ventilation Tech equipment Clean finishing

• • • • •

Diffuse lighting Soundproof room Natural ventilation Tech equipment Technological finishing

CERAMIC STUDIO

• • • • •

Diffuse lighting Open sound room Forced ventilation Tech equipment Dirty finishing

• • • • •

PA I N T I N G S T U D I O

• • • • •

Diffuse lighting Open sound room Natural ventilation Dumb equipment Dirty finishing

• • • • •

FA B - L A B

Diffuse room Soundproof room Forced ventilation Tech equipment Clean finishing

Diffuse lighting Open sound room Natural ventilation Dumb equipment Clean finishing

READING

Diffuse lighting Soundproof room Natural ventilation Dumb equipment Dirty finishing

Diffuse lighting Open sound room Natural ventilation Dumb equipment Clean finishing

SCU L P TU R E STU D IO

D I G I TA L

Raw

COMPUTER

Diffuse

Sound

Soundproof

STUDIO

Programs

ROOM

Diffuse lighting Soundproof room Natural ventilation Dumb equipment Clean finishing

MANUAL SKILLS LAB • • • • •

Diffuse room Soundproof room Forced ventilation Tech equipment Dirty finishing

Criterias for space evaluation The programs’ contamination strategy explained in the Observing chapter has explained how cultural programs will be added to the typical political office spaces in order to function as magnets for developing public attendance to the building. All the programs added will require the adaptation of the existing spaces of the town hall in order to accomodate properly the activities and their proper performance. The wall, floor and ceiling systems will ,therefore, be enriched with multiple specific layers which ensure the adaptation of the space. Therefore, the architectural system exposed by the core cut will then give back a even more varied and interesting output. 110

111

Proposing

Programs Diffuse lighting

Programs

Existing

0 10 cm

Soundproof

10 cm

50 cm

Adapted

Adapted 1

42 1

Skylight 1. Plaster board _ 12mm 2. Clay Hallow pot_ 160 mm 3. Concrete layer _ 40mm 4. Sloped screed 5. Insulation layer_50mm 112

6.Waterproof membrane _ 10mm 7.Aluminium window frame + double glass 16mm+6mm+12mm

Soundproofing system 1. Timber battens+ insulation _ 100mm 2. Resilent bars 3. Acoustic mambrane_18mm 4. Plaster borad _ 12mm 113

Proposing

Programs

Proposing

Programs Tech equipment

Forced ventilation

Existing

0 10 cm

0 10

50 cm

Adapted

Adapted 6

Forced ventilation 1. Tech equipment 2. Hanger wire + adjustable clip 3. Gypsum board _ 12mm 4. Insulation layer _ 50mm 5. Ventilation pipe 6. Exhaust system 114

2 1

Tech equipment 1. Suspended wire 2. American truss 3. Tech equipment 115

Proposing

Programs

Proposing

Programs

Tech finishing _ Dance studio

Existing

0 10

50 cm

10 cm

50 cm

Adapted

Adapted 1

Sprung floor system 1. Hallow pot floor slab _ 300 mm 2. OSB panel _18mm 3. Timber battens _ 100mm 4. Insulation _ 100 mm 5. Acoustic membrane_ 18 mm 116

Tech finishing _ Music studio

42 1 3

6. Rubber shock pad _ 7.9 mm 7. Cross laminated beams _ 18mm 8. Plywood deck _ 18 mm 9. Dance vinyl _ 2.5 mm

Music studio 1. Timber battens+ insulation _ 100mm 2. Resilent bars 3. Acoustic mambrane_18mm 4. Plaster borad _ 12mm

5. Absorber panel_45mm 6. Diffuser panels _ 55mm 7. Ceiling diffuser panels_55mm

117

118

119