fabric architectureinspired by nature: beautifully practical tensile structures

Fabric Architecture have been specialising in the design,

manufacture and installation of Tensile Fabric Structures

since 1984.

The company specialises in both bespoke design and build

structures as well as pre-designed and engineered "off the

shelf" Signature Structures with 5000 installations

throughout the world.

The staff bring over 25 years experience in the field of

fabric architecture, from concept to visualization, design,

engineering, manufacture and installation.

Nigel Browne, one of the two Partners has won The British

Design Award and been nominated for The Duke of

Edinburgh’s Design Award for his work in the field of

tensile design. He is the only RIBA (Royal Institute of

British Architects) certified presenter in the area of tensile

structures, giving seminars to architects to qualify for their

Continued Professional Development certifications.

Fabric Architecture operates to ISO 9001- 2000 standards.

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About Us

Complete Design and Build project from concept to

completion for St Thomas Moore Catholic College, Stoke on

Trent. Bespoke curved conic walkway and 18 metre

diameter conic supported by tripods with integral drainage

and flying masts. Euroflood mini lighting and metal halide

bulbs with coloured gels.

Conic walkway 9m x 35m

Performance flying conic 18m diameter

Type 2 pvc canopies with built in rainwater handling using

perimeter barrier strip.

Steelwork zinc rich primed with 2 pack epoxy paint to RAL

234

Supporting steelwork mounted on C30 concrete slabs with

no reinforcement using chemical anchors with 200mm

penetration.

Installation time 5 days.

Project Notes

This distinctive application

provides large covered

areas which could not be

achieved with conventional

building techniques for the

same budget and minimal

groundworks.

Clients & projectsinclude:BDP ArchitectsCostainDisneyworldJohn LaingPartnershipBAABovis LendleaseHeathrow Terminal 5Glasgow Fort RetailParkIkeaMiller ConstructionAsda

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Project Snapshot

Fabric Architecture has taken centre stage in the £34m

Aintree Racecourse grandstand redevelopment, which

opened in time for the Grand National in April 2007.

The tensile membrane roof of the six-storey link building

that joins the two new stands has pushed this exciting

construction medium to a new frontier. In Building Design

Partnership’s original design, the tensile started life as a

conventional tin roof, matching those of the grandstands.

Fabric Architecture was invited to develop an alternative

scheme within the existing budget.

Early attempts to emulate BDP’s roof concept took a

form which is best described as a giant “pringle” crisp.

To improve coverage and shelter the shape morphed into

a three-cornered pringle with a continuous curved wave

edge beam and concealed gutter. However it was

becoming apparent that to successfully support this form

was unrealistic and a radical rethink was required.

Confined by the base structure, which was rapidly

coming out of the ground, Fabric Architecture side-

stepped from a parabolic to a conical form. With a bi-pod

perimeter mast system pulling the fourth floor pre-tension

slab into compression, three supporting masts, and the

second floor slab into tension, the maths started to work.

The remaining engineering problem was how to get the

edge gutters linking both grandstands to work. The

tensile membrane roof was exerting large asymmetric

loads that neither grandstands had been engineered to

accept. To absorb these massive loads, an inventive

double hinge was developed at one end of each of the

Aintree triple crown1 Original flat roof design

2 Pringle design

3 Three-cornered hat design

4 Rainwater issues

5 Resolution of rainwater

management

6 Loading analysis of canopy

7 3D of final design

8 Gutter hinge connection

detail

9 Gutter hinge installed

10 Gutter connection to

“floating” mast

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1.5 tonne gutters, while the other end was supported on

a floating bi-pod. This effectively dampened the loads

from the “live” tensile structure to the static grandstand

buildings and could allow up to 120mm of movement

under extreme weather conditions.

The final fabric form now needed to be engineered with

particular consideration to water management. Dam

gutters were incorporated to direct water into the two

gutters and off the canopy at agreed points to avoid the

public and horses below.

The fabric was extensively tested to understand its

characteristics, as every batch has subtle differences that

have to be compensated for so that when the fabric is

welded together, it fits perfectly.

To ensure that such a large piece of fabric could be

installed safely in the middle of winter, during potentially

poor weather, a lifting system, nicknamed the Christmas

tree, was designed. This bolted on top of the three

pin-mounted masts, which in turn were linked together

and stabilised in a cobweb of cables and winches.

Prior to the mast erection, the 600m2 fabric canopy

was laid out on the 4th floor, the masts installed and then

the fabric hoisted via the Christmas tree up to an

intermediate position. The masts were designed as a

two-part telescopic system, and jacked up to finally

tension the fabric to its final form.

The structure was a huge success during the Grand

National weekend, hosting a large corporate contingent

both in comfort and out in the open air.

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Senior designer and Partner, Nigel Browne

travels throughout the UK giving CPD

presentations to Architects and Designers on

how to design a tensile structure. As a

building medium, fabric requires a different

approach to that of conventional roofing

materials, and offers limitless possibilities of

three-dimensional forms.

Q: Why Fabric?

A: Fabric can achieve far greater spans than

conventional roof materials with minimal supporting

structure. Greater translucency and dynamic, organic

shapes brings the feeling of outside inside, as well as

providing shade and protection from the weather.

Tensile structures generate live loads instead of the

static loads of conventional roof materials and modern

architectural fabrics offer increased stability and

longevity of over 20 years.

Q: What are the advantages in using Fabric?

There is an economy of cost per square metre, strength

and longevity with fabrics compared with concrete and

steel construction. The significant cost saving is the

reduction in installation time required, with support

structure and fabric membrane pre-fabricated and

assembled on site.

Tensile fabric shapes breathe life and excitement into a

building, and blend steel construction with organic fabric

forms. This provides shade and weather protection from

a low maintenance material, reducing UV transmission

and controlling solar gain.

Q: Is this an environmentally

sensitive solution?

A: Tensile fabric structures significantly

reduce the volume of materials required in

construction, therefore reducing the carbon

footprint of the project.

The future of design and construction

demands greater use of renewable materials

and reducing carbon emissions. Over the

last 3 years, a specially developed silicone-

coated glass weave material has been

introduced by Fabric Architecture and used

on a growing number of projects. The

material is totally inert and recyclable as it is

almost entirely made from silicone, a

naturally occurring element.

Nigel Browne Senior design partner

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Technical briefing

Hypar form

There are 3 basic forms of a tensile

structure which incorporate double

curvature to create the strength and

organic design.

Barrel vault form

Conic form

Q: Where to start?

A: A tensile structure should be viewed as an

integral part of a building, rather than a last minute

add-on, even though it is categorised as an optional

extra. It should be included in the design process

from the concept stages, and address the following:

• Determine the loads that will be exerted on

connecting buildings and/or ground

• Calculate and locate foundation pads

• Locate services adjacent to foundations and re-

route

if required

• Manage rainwater run-off

• Is there are need for lighting and security?

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Property PVC/Polyester silicone/fibre glass PTFE/fibre glass

Life expectancy 10-15 years 30+ years 30+ years

Burning Polyester combustible glass non-combustible glass non-combustible

Characteristics PVC – flame retardant silicon –inherently flame retardant PTFE – inherently flame retardant

Toxicity during CO/CO2 CO/CO2 only above 290˚ C HF,

Combustion Halogens, traces of Dioxin non toxic fluorine compounds

Oxides of N

FDA (Food Approval) None certain grades FDA, BgW approved approved

Light Transmission up to 20% up to 30% up to 20%

UV light transmission No Yes UV-B and UV-C filtered No

Allows photosynthesis mainly UV-A transmitted

Colour any colour limited limited

Bleaching n/a not necessary tan, until bleached with time

Cost low-medium medium-high high

Soiling Behaviour medium very good excellent

Chemical resistance good very good excellent

Capillary Rise < 20 mm < 2 mm no data yet

Temperature Range -30 to 70˚ C -55 to 200˚ C -20 to 260˚ C

Stiff below -20˚ C

Tensile strength medium high high

Tear strength medium high high

Dimensional stability medium high high

Flexibility high excellent low

Reuseability possible yes with difficulty

Joining Techniques Welding Stitching/Sewing with Tenara glass thread Thermal splicing with aid of

or bonding with silicon adhesives FEP tapes

Recycling Yes Yes n/a

Membrane comparison table

fabric architecture

Unit B4 Nexus, Gloucester Business Park Hurricane Rd, Brockworth, Glos. GL3 4AGT +44 (0)1452 612800 F +44 (01452) 621200 E info@fabricarchitecture.com

Signature StructuresWhat are Signature Structures?

A range of specially selected tensile fabric designs popular

for their shade, shape, application, ease of installation and

long life.

Steelwork can be painted to any RAL colour and canopies

are available in a range of colours.

Engineered to 50 year wind cycles with installation in

1 to 2 days. Many designs can be joined together while

multiple freestanding units create dramatic visual impact.

Signature Structures deliver the

organic beauty of design and build

tensile structures yet they can be

customised and are easy to specify.

Alternatively, they act as an excellent starting point

from which exciting new possibilities can be developed.

Options include:

Lighting and heating

Fabric type and colour

Steelwork paint colour

Building connections

Drainage