Church Structural and Planning Advances from Romanesque to thelate Gothic

Romanesque, according to the Collins English Dictionary1, is

denoting or having the style of architecture used in W and S Europe from the 9 th to

the 12th centuries, characterised by the rounded arch and massive masonry wall

construction.

Gothic, according to the same dictionary, relates to the style of

architecture that was used in W Europe from the 12th to the 16th centuries,

characterised by the lancet arch, the ribbed vault and the flying buttress.

These two rather dry definitions do not do justice to a period

of advance in architectural stone engineering that resulted in

remarkable innovations in cathedral design and structure at

that time. The defining feature of the progression was the

growing understanding by the master masons of the importance

of lines of thrust. Through experience, experimentation and

the sharing of knowledge, buildings were created that

evidenced an emerging tacit understanding of structural

mechanics: an understanding that gave them the confidence to

place the structural components of a building only where they

were needed.

This confidence not only released areas of the building

structure for increased window area and opportunities for non-

structural decoration, it also significantly reduced the

weight of the masonry and allowed much taller buildings to be

created.

1 Lorna Knight (Ed). Collins English Dictionary and Thesaurus. (Glasgow, 1995)

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This brief essay will trace that developmental process in

Britain with particular reference to Gloucester and Oxford

Cathedrals and Ewenny Church in Glamorganshire.

The history of architecture has followed that of the

civilisations that created it. At times of great strength,

stability and prosperity, civilisations have grown and the

arts, science and architecture have grown with them2. As they

declined, each left an architectural legacy in the ruins for

use by future generations.

Although the motifs survived, however, the skills did not. In

past periods of conflict and social fragmentation the tacit

knowledge contained within the skilled community of practice,

there being nothing in print, was lost. The growing

architecture of a new civilisation, then, necessarily began

with a period of re-invention and re-skilling before

innovation was added. This was the situation at the end of the

first millennium as Europe emerged from the Dark Ages.

It might be said that the Romanesque period represented the

re-invention phase in medieval European church architecture,

and that the Gothic period was the innovation phase.

Gilbert Scott3 described how the skills the Romans had

developed in arctuated architecture had been largely lost

during the dark ages, but that knowledge of the art remained.

He describes how, in Western Europe, ‘… nearly every structural change

which we trace from the tenth to the thirteenth century arose, more or less, from the

2 Kenneth Clark. Civilisation. (London, 1969)3 Sir Gilbert Scott. Lectures on the Rise and Development of Medieval Architecture. (London, 1879)

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endeavour first to revive and then to carry on to higher and higher perfection the

construction of arches and vaulting.’

The priory church of St Michael at Ewenny in Glamorganshire

has many of the typical features of Romanesque architecture

identified by Scott: round arches, barrel and groin vaulting

and ‘… great thickness of walls to resist the thrust of vaulting, aided by flat,

pilaster-like buttresses in the principal planes of pressure.’

Ewenny church: nave arcade and

aisle4

Ewenny church:presbytery

Ewenny church: presbytery, east end

Although4 the church has no independent buttresses, it has a

cruciform layout and the transepts, although partially

demolished, provide the external abutment support needed to

resist the outward thrust of the tower. The original barrel-

vaulted side chapels that provided similar abutment for the

presbytery, however, are no longer in place and this has led

to a visible distortion of the vault. The distortion

accurately maps to the barrel vault deformations described by

Huerta5 and shows how the master builder at Ewenny understood

what was needed to ensure structural integrity and it was only

compromised by the later collapse of the side chapels.

4 All photographs & diagrams original except where attributed.5 Santiago Huerta. Mechanics of masonry vaults: The equilibrium approach. (Madrid, 2001)

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Ewenny church: north transept Ewenny church: ribvaulting

Barrel vault deformation: from Huerta5

There was a pragmatic understanding and application of how

buildings stood up under their own weight. It was based on

what Huerta described as a … (deepening) insight in the nature and

behaviour of masonry structures. He referred to Heyman6 who described,

in his safe theory for masonry structures, how they understood that a

building will stand if the compressive network of

gravitational forces is contained within the structure.

The problem with the barrel vault was that the walls had to be

massive to support it and windows, if they were included at

all, were necessarily small. The main light source was from

windows at the ends as in the presbytery at Ewenny. This was

addressed by creating a groined vault where two barrel vaults

intersected at right angles, allowing windows to the side as

well as the ends. This can be seen in the eastern end of the

Ewenny presbytery. Another solution was the addition of

vaulted aisles that abutted the main body of the church and

allowed the main body to be raised on arcades of massive

columns and a clerestory level of windows to be introduced.

Solid external buttresses were also common.

6 Heyman, J. Equilibrium of Shell Structures. (Oxford, 1977)

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The transition from the Romanesque to the Gothic was marked by

the introduction of the pointed arch7. This had the effect of

directing the gravitational line of thrust around the arch

creating a greater vertical component and reducing the lateral

thrust. The development of ribbed vaulting on the inside of

the church and flying buttresses on the outside represented an

extension of this approach. It came with the growing

realisation that the gravitational lines of thrust within a

building can be accommodated using a strong skeletal structure

that exactly matched those lines of thrust. This development

was eloquently described by Heyman in The Stone Skeleton8.

The Gothic builders created skeletal supporting structures of

flying buttresses which avoided unnecessary weight and

directed the forces to the ground in a much more efficient and

precise way. The technique included mechanically loading key

points in the roof to ensure that the vertical lines of force

were directed accurately through the walls, pillars and

buttresses and that all lateral forces were both minimised and

in balance.

The consequence was a dramatic development in church and

cathedral design as a result of making the wall areas that

were not structural available for other purposes, particularly

windows. A further benefit was the significant reduction in

the weight of the building that allowed much taller structures

to be created; a feature that appealed to both the clergy in

7 Hubert Pragnell, Architectural Britain. (London, 2007)8 Heyman, J. The Stone Skeleton: Structural engineering of masonry architecture. (Cambridge, 1995)

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their glorification of god, and the authorities in their civic

pride.

Gloucester cathedral provides an excellent opportunity to

trace the development from the Romanesque through to the late

Gothic as it continued in its construction throughout that

era9. The nave arcades of massive drum pillars and the

triforium above them are Romanesque, as is the vault of the

northern aisle with its semicircular diagonal and transverse

ribs. It is interesting to note the solidity and clear

structural purpose of these ribs, compared with the fragility

of those at Ewenny which Thurlby10 regards as ‘… a fine illustration of

the purely aesthetic application of this motif.’

A comparison of the north aisle with the south aisle shows the

transition to gothic. As a

Gloucester cathedral: nave and southaisle

Gloucester cathedral:north aisle

Gloucester cathedral: southaisle

result of instability created by unbalanced thrusts from the

Romanesque vault, the south aisle was rebuilt in 1318 and the

roof and windows replaced in the Gothic style. The semi-

9 David Verey & Alan Brooks. Gloucester: An Architectural Guide. (New Haven Ct, 1970)10 Malcom Thurlby. The Romanesque Priory Church of St Michael at Ewenny. (JSAH, Sept 1988)

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circles of the north vault contrast with the pointed arches in

the south, and the south windows are Decorated Gothic with

ballflower ornamentation.

The progressive development of Gothic architecture may also be

seen in the development of the lancet window from its basic

form, through the decorated style in the 13th and 14th

centuries, to the perpendicular style from the 14th century

which Gloucester has in abundance. The perpendicular window

style at Gloucester has structural as well as aesthetic

features. Supermullions extend from the walls below the vast

windows to the roof above and delicate flying buttresses

provide additional support from the outside.

Oxford cathedral: lancetwindows8

Gloucester cathedral:decorated Gothic

Gloucester cathedral: perpendicularGothic

The buttressing at Gloucester cathedral also traces the

development of the Gothic style as structural masonry grew

more sophisticated. There is evidence of both bold innovation

and also pragmatic retro-fitting in the building; buttresses

cutting ruthlessly across windows and arches where necessary.

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Gloucester cathedral: externalbuttressing

Gloucester cathedral:window buttressing

Gloucester cathedral: internalbuttressing

By the end of the Gothic

period the master builders had

reached a level of

sophistication that allowed

them to create soaring

cathedrals with the minimum of

weight and maximum of window

space as a result of their

understanding of structural

engineering. A greater

emphasis on the aesthetic

rather than the structural was

available to both designer and

patron.

By now, rooflines had become

flatter, particularly with the use of lead as a roofing

material which allowed water to be removed at a much lower

pitch than slate or stone. This led in turn to flatter

internal structures and firstly lierne and then highly

intricate web vaulting was made possible.

Web vaulting is, perhaps, the feature that epitomises the

achievements of the late Gothic stonemasons. It demonstrates

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Flying buttress lines of thrust: from Huerta5

how an exquisite understanding of structural mechanics was

employed in the design of elaborate ceilings where seemingly

decorative features such as the hanging pendant were actually

key structural components that helped direct thrust through

the transverse ribs.

Gloucester cathedral: lierne vaulting Oxford cathedral: fanvaulting

Oxford cathedral: fanvault pendant

The use of relatively slender pillars as the key supporting

components of late Gothic structures also demonstrates the

confidence that the master builders now had in their designs.

Complex groups of shafts replaced columns, emphasising the

strong vertical feeling in the buildings and this was

reinforced at Gloucester by the supermullions that extended

from floor to ceiling.

Christ Church, Oxford: fan vault pillar support

Gloucester cathedral:supermullions

Oxford museum: cast ironskeleton

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The use of a strong structural frame for a building which is

then clad in relatively lightweight materials is still the

basis of high rise building design today. This is no better

illustrated than in the cast iron skeleton of the Oxford

University museum.

The structural principles that were developed and employed by

the Gothic builders were later documented by Alberti11,

Palladio12 and others, printing and book publishing having been

invented in the 15th century, and were gradually articulated in

theory from the 17th century onward. There are those who

suggest that, with the lack of underpinning scientific theory

at the time, medieval builders somehow achieved what they did

through trial and error but, as both Huerta5 and Heyman8 point

out, this is a serious misinterpretation of their methods. To

paraphrase Huerta: The Gothic masters developed a ‘scientia’ and this scientia

was firmly based on geometry, proportion and equilibrium.

This brief overview of the advances in church structure and

planning from the Romanesque to the late Gothic periods has

attempted to demonstrate that a cycle of re-invention and then

remarkable innovation took place. Structural stone engineering

perhaps reached its peak at this time and, as other building

techniques and materials took over in the following centuries,

those practical masonry skills have largely been lost.

11 Leon Battista Alberti. De re Aedificatoria. On the art of building in ten books. (Cambridge, Mass, 1988)12 Andrea Palladio. The Four Books of Architecture. (London, 1738)

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Bibliography

Alberti, Leon Battista. De re Aedificatoria. On the art of building in tenbooks. (Cambridge, Mass. MIT Press, 1988)

Clarke, Kenneth. Civilisation. (London, 1969)

Heyman, J. Equilibrium of Shell Structures. (Oxford, 1977)

Heyman, J. The Stone Skeleton: Structural engineering of masonry architecture.(Cambridge, 1995)

Huerta, Santiago. Mechanics of masonry vaults: The equilibrium approach.(Madrid, 2001)

Knight, Lorna (Ed.) Collins English Dictionary & Thesaurus. (Glasgow,1955)

Palladio, Andrea. The Four Books of Architecture. (London, 1738)

Scott, Gilbert. Lectures on the Rise and Development of MedievalArchitecture. (London, 1879) Lecture II.

Thurlby, Malcom. The Romanesque Priory Church of St Michael at Ewenny. ( Journal of the Society of Architectural Historians, Vol. 47, No. 3. Sept 1988)

Opher, Philip. The Cathedral, Parish Churches and College Chapels of Oxford. (Oxford, 2008)

Pragnell, Hubert. Architectural Britain. (London, 2007)

David Verey & Alan Brooks. Gloucester: An Architectural Guide. (New Haven Ct, 1970)

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