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Illumination & Decoration of Flat Surfaces BOB CAMERON SIXTH EDITION

Flat Surfaces

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Page 1: Flat Surfaces

I l luminat ion& Decorat ion

of F lat Sur faces

It must be appreciated that no building surface is perfectly flat and that the best that can be

expected is the appearance of flatness. Unfortunately, this appearance can easily be destroyed

by the effect of glancing light, whether natural or artificial. Illumination and Decoration of Flat

Surfaces shows the effect of different light sources on a variety of lining materials and paints

so that best results can be achieved.

Different types of building surfaces are investigated, including set plaster, fibrous plaster,

hardboard and gypsum board with gloss and semi-gloss paint applied. This full-colour

edition also discusses new building materials such as cement sheet, polystyrene and various

composite panels, as well as new building practices, low embodied energy materials and

higher energy efficiency of buildings.

Illumination and Decoration of Flat Surfaces is a must-have for people involved in the building

industry, both commercial and residential.

BoB Cameron

SIxTh eDITIon

Page 2: Flat Surfaces

BOB CAMERON

I l luminat ion& Decorat ion

of F lat Sur faces

SIXTH EDITION

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Page 3: Flat Surfaces

Published by

Landlinks Press

150 Oxford Street (PO Box 1139)

Collingwood VIC 3066

Australia

Telephone: +61 3 9662 7666

Local call: 1300 788 000 (Australia only)

Fax: +61 3 9662 7555

Email: [email protected]

Web site: www.landlinks.com

Landlinks Press is an imprint of CSIRO PUBLISHING

Front cover photo by iStockphoto

Back cover photo by Bob Cameron

Set in 9/14 Vectora

Cover and text design by James Kelly

Typeset by James Kelly

Printed in Australia by Metro Printing Pty Ltd

First published by CSIRO Division of Building Research as

Report No. L8, 1960 (ISBN 0 634 00299 5), reprinted 1978,

1981, 1984; then as Technical Report TR 90/1, 1990

(ISBN 0 643 05085X), reprinted 1992.

CSIRO PUBLISHING publishes and distributes scientific,

technical and health science books, magazines and journals

from Australia to a worldwide audience and conducts

these activities autonomously from the research activities

of the Commonwealth Scientific and Industrial Research

Organisation (CSIRO).

The views expressed in this publication are those of the

author(s) and do not necessarily represent those of, and

should not be attributed to, the publisher or CSIRO.

Photo credits: Keith Cochrane – pp. 2, 3; Bob Cameron –

pp. 4, 5; Brett Grimley, Ecolibrium Design – pp. vii, 19, 20;

Ken Waddington – pp. 6, 7, 8, 9, 10, 11, 12, 13, 14, 15

© CSIRO 2009

All rights reserved. Except under the conditions described in the Australian Copyright Act 1968 and subsequent

amendments, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any

form or by any means, electronic, mechanical, photocopying, recording, duplicating or otherwise, without the

prior permission of the copyright owner. Contact Landlinks Press for all permission requests.

National Library of Australia Cataloguing-in-Publication entry

Cameron, Bob.

Illumination and decoration of flat surfaces / Bob Cameron.

6th ed.

9780643094901 (pbk.)

Bibliography.

Walls.

Coatings.

Interior lighting.

Lighting, Architectural and decorative.

729.28

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Page 4: Flat Surfaces

iv Preface

vii Abstract

ix Introduction

1 Glancing light on flat surfaces

17 Avoiding the effects of glancing light

19 Colour, lighting and energy efficiency

21 Plasterboard

23 External lightweight cladding

25 Gloss paint on flat surfaces

27 Recommendations

29 References and links

C O N T E N T S

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Page 5: Flat Surfaces

P R E F A C E

One of the first things a young plasterer is told by his older colleagues

and mentors is ‘the sun is our harshest critic’. In fact, it is not only

the sunlight but sidelight from any source that will show up even

the tiniest imperfection in hand-finished surfaces. This effect can be

further exacerbated by the use of gloss paints.

It was early in my plastering career, while applying a polymer bound

aggregate finish to the external walls of a unit development, when I

first encountered this phenomenon. Although this was a relatively new

technique at the time, the job had been progressing well and we had

been able to achieve what we thought was a very high standard of

finish. I was quite surprised when I received a frantic call from the site

foreman informing me that when the scaffold had been taken down

there were areas where the work was not up to standard. ‘Looks

like it has been thrown on with a shovel’, I believe were his exact

words. Incredulous that the walls we had so carefully finished with our

stainless steel trowels should attract such comments, I told him that

I would come down immediately and inspect the work myself. I was

then informed this would not be suitable for it was now mid-afternoon

and the walls were in the shade and apparently looked quite OK. I

met with the builder and architect on site the following morning at

precisely 10:15 am, when the sun would be throwing a glancing light

across the offending walls, to inspect the substandard workmanship

and propose a plan of action to rectify the situation. What followed

was a protracted series of site meetings and discussions between

architects, builders and tradesmen as well as experts of many

persuasions to finally arrive at the conclusion, so simply explained in

this book, that the work had been completed as well as practically

Page iv Illumination & decoration of flat surfaces

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Page 6: Flat Surfaces

possible. In the end no further action was taken and to the best of my

knowledge the walls have remained the same to this day.

It has been with great pleasure that I have undertaken the task of

updating this excellent and very useful publication. It is a superb

example of how the application of science can be of enduring

practical value to such an ancient trade as plastering and painting –

not by addressing the materials and processes themselves, but by

looking at the design and how these components are arranged to

achieve the desired outcome as economically as possible.

In updating the manuscript it has been important to retain the

simplicity of the original text and not overburden the book with

technical details. Instead we have included links to various websites

where this information can be found, in its most recent and up-to-

date form, or to other publications dealing with the specific topics.

Some of the changes that have occurred in the building industry

within Australia since the publication of the original edition include

the rise in the use of plasterboard and the almost complete

disappearance of fibrous plaster. Plasterboard has also replaced a lot

of hard-set plaster, although not to the same degree, and there is still

plenty of hard-set plaster used in some areas.

Significant changes have occurred in the external surfaces, with

rendered finishes becoming far more popular, making inroads into

the dominance of face brick and in some areas almost completely

replacing it. Greater awareness of energy efficiency has encouraged

the use of lightweight insulation systems, which also include a

rendered finish.

Page vPreface

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Illumination & decoration of flat surfacesPage vi

These trends, along with the continued push for higher quality

finishes at reduced costs, have greatly increased the need for this

new edition.

Part of the reason is the higher expectations from both the industry

and consumers, supported by a number of developments within the

industry. Modern building design and construction methods allow for

increasingly larger windows with fewer beams, pelmets and columns,

allowing light to enter the interior of the building almost parallel to the

wall and ceiling surfaces. Often these windows receive reflected light

from adjacent building surfaces or from water.

LEVELS OF FINISH

Australian/New Zealand Standard AS/NZS 2589:2007 defines

three levels of finish for plasterboard linings, covering the different

specifications for the framing, installation, finishing and decorating

required to achieve the various levels of finish. It is imperative that

the required level of finish is determined at the design stage of the

project with full consideration given to the lighting and decorative

finishes to be used.

Bob Cameron

Rockcote Enterprises Pty Ltd

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Page 8: Flat Surfaces

No building material has an absolutely flat surface; in practice, all that

may be expected is an appearance of flatness. This book reviews

the effect of glancing light on the appearance of flat surfaces of

hand-finished plaster, cement render and applied finishes, including

internal plaster finishes such as hard-set plaster, plasterboard and

fibrous plaster, as well as external surfaces such as cement render,

cement sheet and applied coatings. It shows that surfaces which

seem perfectly flat in diffuse light appear rough and uneven when lit

by light falling nearly parallel to the surface. The conclusion is drawn

that glancing light must be avoided if the appearance of flatness is

desired. Some practical ways of achieving this are discussed together

with the effects of gloss and semi-gloss paints on the appearance of

flat surfaces.

A B S T R A C T

Figure 1: The surface texture or imperfections that are not visible under diffuse light or where light of similar intensity strikes the surface at different angles (left), become obvious when light strikes the surface from one direction at an acute angle (right).

Page viiAbstract

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Plain, flat surfaces are an important feature of building design. Flat,

unbroken surfaces free from distracting detail create an attractive,

spacious effect which is very popular in both commercial and

domestic buildings.

No hand-finished building material has a surface that is any better

than an approximation of flatness and this is true of all the common

lining and cladding materials used for large areas of unbroken

surfaces. To produce a surface approaching anything a physicist

would accept as flat would require the expenditure of thousands of

dollars on precision grinding, and therefore a building surface that is

perfectly flat is not practicable with present technology. In the building

industry the aim is to produce the appearance of flatness.

If the decorative effects of flat surfaces are desired, the true nature

of practical building surfaces must be considered when illumination

or use of paints is planned. Incorrect lighting or decoration can

completely destroy the illusion of flatness. The effects of glancing light

and gloss paint are examined in this book.

I N T R O D U C T I O N

Page ixIntroduction

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It is economically impracticable to produce a building surface that is

flat in the literal sense of the word. Even slight deviations from true

flatness can cause light falling nearly parallel to the surface – for

example, glancing light or sidelighting – to cast shadows that are

irregular in shape and distribution. On a plain wall where there is no

pattern of irregularities to distract the eye, such shadows are very

noticeable and completely spoil the effect gained by elimination of

cover strips, V-joints and other ornamentation. They are most

noticeable when all the light comes from one direction and thus

there is no other illumination to dilute them.

Some striking examples of shadows cast by glancing light are shown

in Figures 2–6. Figure 2a shows the rendered wall of a building as it

appears under most conditions of natural lighting. Figure 2b shows

the same wall during the brief period when sunlight just skims the

surface, and here the wall presents a very different appearance

from that shown in Figure 2a. Shadows cast by differences in level

that were hardly noticeable in ordinary light give a rough, broken

impression and exaggerate the texture of the wall. Shadows are

cast by slight differences in level caused by the floating and

finishing of the surface.

G L A N C I N G L I G H T O N F L A T S U R F A C E S

Glancing light on flat surfaces Page 1

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Illumination & decoration of flat surfacesPage 2

Figure 2a: Rendered wall under standard daylight.

Fortunately the sun remains in this critical position for only a very short

period and its ability to reveal different textures in exterior surfaces

is not particularly important. This is not the case, however, when the

lighting of interior surfaces, especially artificial lighting, is considered.

Here the effect is not transient, as in the case shown in 2a and 2b,

but under unfavourable circumstances can be just as striking and the

effect is permanent while the unfavourable light is directed.

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Figure 2b: The same rendered wall as it appears when the sun’s rays are nearly parallel to the surface (glancing light).

Glancing light on flat surfaces Page 3

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Illumination & decoration of flat surfacesPage 4

Figure 3a: An area of a rendered wall as it appears by diffuse light.

Figures 3a and 3b further illustrate this point by showing another

example of a rendered wall under both standard and glancing

sunlight conditions, then showing the same wall illuminated by

glancing light from a wall light placed close to the surface in Figure

3c, which had just been painted with a sealer and two coats of matt

finish paint.

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Page 16: Flat Surfaces

Figure 3b: The same area of rendered wall as it appears in glancing sunlight.

Figure 3c: The same area of rendered wall showing the effects of a wall mounted light.

Glancing light on flat surfaces Page 5

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Illumination & decoration of flat surfacesPage 6

Figures 4a and 4b show the same area of set plaster identified

by a pair of drawing pins. In diffuse light the area seems quite flat

and featureless but this appearance is completely destroyed by

glancing light. Shadows and irregularities are now visible and it is

even possible to see the track of the trowel as it was moved over the

surface during polishing although the quality of workmanship was

high. These marks were invisible in diffused light.

Figure 4a: An area of hard-set plaster under standard lighting conditions.

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Figure 4b: The same area of hard-set plaster shown in Figure 4a as it appears by glancing light.

Glancing light on flat surfaces Page 7

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Illumination & decoration of flat surfacesPage 8

Figure 5a shows an area of flush-jointed fibrous plaster as

it appears by ordinary light. Figure 5b shows the same area

illuminated by glancing light, which has revealed minute

differences in level and the positions of the flush joint and

stoppings. The flush joint was of the highest workmanship and

could not be detected when a joint rule was run over the surface.

Figure 5a: An area of fibrous plaster as it appears by diffuse light.

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Page 20: Flat Surfaces

Figure 5b: The same area of fibrous plaster shown in Figure 5a as it appears by glancing light.

Glancing light on flat surfaces Page 9

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Illumination & decoration of flat surfacesPage 10

Figures 6a and 6b show an area of gypsum board by ordinary

light and by glancing light. Once again the illusion of flatness is

completely destroyed by shadows cast when the light is nearly

parallel to the surface.

Figure 6a: An area of plasterboard wall under normal lighting.

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Page 22: Flat Surfaces

Figure 6b: The same area under sidelight.

Glancing light on flat surfaces Page 11

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Illumination & decoration of flat surfacesPage 12

Figures 7a and 7b show the effects of ordinary and glancing light on

an area of hardboard containing a V-joint. The effects are similar to

those produced in the previous cases.

Figure 7a: An area of cement sheet containing a V-joint as it appears by diffuse light.

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Page 24: Flat Surfaces

Figure 7b: The same area of cement sheet shown in Figure 7a as it appears by glancing light.

Glancing light on flat surfaces Page 13

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Illumination & decoration of flat surfacesPage 14

Figure 8a is an example of a cement sheet wall with the joints taped

and set and a polymer render applied over the entire wall with the

objective of achieving an even rendered finish (Level 4). However, this

lightly textured sand finish shows up all the panel joints under the

severe sidelight of the early morning sun. This is a particularly good

example in that it is evident the builder has gone to considerable

effort to provide a flat surface by ensuring that the sheets run the full

length of the 3 m high wall, eliminating any horizontal joints.

Figure 8a: Cement sheet (Level 4) with the joints taped and set with an applied finish.

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Page 26: Flat Surfaces

Figure 8b shows the same wall a little later in the morning, a seamless

rendered finish with no imperfections evident under normal daylight.

The illustrations show the immense changes in appearance that

occur when illumination by glancing light is substituted for diffuse

light. The effects make it quite clear that if the appearance of flatness

is desired, it is necessary not only to have walls of good workmanship

but also to ensure that illumination is designed to avoid glancing light,

which can reveal the surface texture.

Figure 8b: The same wall area as Figure 8a under standard light.

Glancing light on flat surfaces Page 15

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The worst effects are produced when a single unshaded lamp is

placed close to a wall or ceiling (as in Figure 3c), in an otherwise

darkened room or area. For example, the light cast by isolated,

unshaded fluorescent tubes fixed directly to the ceiling has particu-

larly severe effects on the appearance of adjoining surfaces. In this

case, putting the tube about 45 cm below the ceiling will ensure a

much better distribution of light and help make the irregularities in

the surface much less noticeable.

The problem is less acute in rooms lit by a number of more or less

evenly spaced units such as those used in large offices. Here, more

diffused light helps to dilute the texture-revealing shadows cast by

individual lamps, and surface irregularities will be less noticeable. Two

closely spaced rows of lamps will each negate the texture-revealing

shadows produced by the other in the area in between. In small

rooms, light reflected by the walls, particularly light-coloured walls,

produces a helpful diffused component in the lighting. Light-coloured

floors and furniture also help.

An alternative to suspending lamps below the level of the ceiling

is to put them above it, in recesses. Fluorescent tubes are ideal

for this treatment and attractive light recesses are available from

manufacturers of fibrous plaster. This treatment is quite satisfactory

in purely decorative interiors where a dark ceiling is required or

illumination of the ceiling doesn’t matter. However, in working interiors

such as those in factories, offices and schools, the health and

amenity for the worker must be considered and some loss in the

appearance of the surface may have to be accepted.

A V O I D I N G T H E E F F E C T S O F G L A N C I N G L I G H T

Page 17Avoiding the effects of glancing light

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Illumination & decoration of flat surfacesPage 18

Lamps mounted in recesses are liable to cause more glare than those

mounted on or below the ceiling and special precautions must be

taken to see that the ceiling is adequately illuminated by reflected

light or by other means, such as cornice lighting. Australian Standard

No. 1680: 1990 – Code of Practice for Interior Lighting and the Visual

Environment – recommends methods of controlling glare. It is most

important that these recommendations are observed in working

interiors, particularly where any form of recessed lighting is used.

Glancing light also occurs where windows extend to ceiling height or

are adjacent to walls, with the worst effects occurring when there are

narrow windows close to the walls. In these cases, suitable curtains or

pelmets will reduce the effects. The most useful light for the comfort

and efficiency of the worker is that entering at the top of the window

(the part nearest the ceiling), and it may be necessary for appearance

to take second place over other considerations. People tend to be

less aware of the appearance of overhead surfaces than those at eye

level and slight irregularities that would be obvious to a plasterer or an

architect will mostly go unnoticed by the average occupant.

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The benefits of natural light – using diffused daylight reflected off

light-coloured walls – can save energy while increasing the comfort

levels and amenity of the internal environment. This will also reduce

the effects of glancing light on the walls and ceilings. Paint is one of

our most effective lighting tools. Light-coloured matt paint or fine

textured finishes will diffuse and reflect both natural and artificial

light. Diffused light reflected from a number of directions will help

mask minor surface imperfections while creating a more

comfortable environment for the inhabitants. Direct light from a

single source, darker colours and gloss finishes will exacerbate

any surface imperfections.

C O L O U R , L I G H T I N G A N D E N E R G Y E F F I C I E N C Y

Figure 9: A surface mounted light fitting will cast a sidelight across the ceiling, highlighting even the smallest imperfections.

Page 19Colour, lighting and energy efficiency

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Illumination & decoration of flat surfacesPage 20

Figure 11: Align plasterboard joints parallel with wall lighting rather than across the light.

Figure 12: Align plasterboard joints parallel with light coming from a window rather than across the light.

Figure 10: Improved lighting design with the light fittings either recessed into the ceiling or suspended below with reflectors direct the light into the room rather than across the ceiling.

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While plasterboard has been finished the same way for many years,

modern buildings and consumer expectations require a high level of

finish. Plasterboard surfaces are of particular concern in respect to

the effects of glancing light. This is due to the nature of the materi-

als, standard industry practice and consumer expectations. The

plasterboard itself, being a machine-finished component, has a

much flatter surface than it is possible to achieve with the hand-

finished plaster joints. So even when the workmanship is of a very

high standard and well within tolerances set by industry bodies, the

wall surface can look very poor under glancing light with the

hand-finished plastered joints ruining the desired flat, even surface.

This method of finishing plasterboard, referred to as a Level 4 finish,

has always been the standard specification for almost all plaster-

board installations throughout Australia. However, this may no

longer be the most suitable system to meet the requirements of

modern buildings and consumer expectations in this country. It may

well be time for Australia to follow the lead of most other western

European countries and specify a higher standard of finish for our

plasterboard linings.

This would require agreement within the industry on exactly what a

Level 5 finish entails and the standard to be adopted by the industry.

Again drawing on overseas experience, the defining feature of the

Level 5 finish is the inclusion of a skim coat of plaster over the entire

wall area. Although such a skim coat is a hand-finished surface, the

imperfections are now overall rather than on joints and visible panels

providing a much more acceptable finished effect. Having an even

surface with the same surface texture and suction characteristics

removes the source of many of the problems currently associated

with the decoration and aesthetics of plasterboard linings.

P L A S T E R B O A R D

Page 21Plasterboard

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Illumination & decoration of flat surfacesPage 22

LEVEL OF FINISH CHARACTERISTICS AND FINISH

Levels 1–2 No longer in use.

Level 3

All joints, internal and external angles taped and set flush with the board surface.

Suitable for areas that do not require a decorative finish such as above the ceiling level, lift shafts etc.

Level 4

All joints taped, set flush and sanded smooth. Fixing heads set flush and sanded. External angles beaded, set flush and sanded.

Currently the default level of finish for plasterboard linings unless specified otherwise. Suitable for decoration with flat or low sheen paints.

Level 5

All joints and internal angles taped and set flush. Reinforcing angle beads fitted to external angles. Skim coat of plaster over entire wall.

Used in areas requiring the highest possible standard of finish. Provides a smooth, flat surface with even porosity and suction.

Table 1: Levels of finish for plasterboard linings

Table 1 outlines only the essential characteristics of the finishing

system for the respective levels of finish. For a description of the

complete system see AS/NZS 2589: 2007 Gypsum Linings –

Application and Finishing.

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Lightweight external cladding systems installed over timber and steel

frame walls have become increasingly popular. This trend was

initially driven by the fashion for rendered finishes and has gained

momentum in recent years with the call for more energy efficient

buildings and building materials.

These systems are based on either cement sheet, expanded

polystyrene, extruded polystyrene or various composite panels. There

are essentially two distinct methods of finishing these systems, each

capable of providing a different standard of finish (see Table 2).

Standard industry practice for finishing cement sheet walls with an

applied finish is to tape and set the joints, prime the wall and apply an

acrylic-based texture coating or polymer-based render. A competent

applicator using this procedure can only count on achieving a Level 4

finish. Under glancing light the panel joints may still be visible. In fact,

these cladding systems fare particularly badly under glancing light,

leading to many complaints from the industry and end users alike.

The problem is similar to the situation with plasterboard in that the

expectation, even from builders and architects, is that setting the

joints and applying 2–3 mm of texture coating should provide a Level

5 finish. The fact is that this is not a practical expectation using this

system, leading to a great deal of dissatisfaction and disputes within

the industry.

To achieve a higher level of finish over lightweight cladding

installations a screeded cement render is the preferred option.

This consists of a polymer modified cement render incorporating a

glass fibre reinforcing mesh. The render is applied to a thickness of

approximately 4–8 mm and the wall is screeded, helping to cover

E X T E R N A L L I G H T W E I G H T C L A D D I N G

Page 23External lightweight cladding

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Illumination & decoration of flat surfacesPage 24

any irregularities in the substrate. This process can provide the

look and feel of a rendered solid masonry wall over lightweight

insulation systems.

A Level 5 finish will still show the normal imperfections under

glancing light that could be expected from any other screeded

render finish; however, the panel joints should not be visible

under any lighting conditions.

Table 2: Levels of finish for lightweight cladding

LEVEL OF FINISH CHARACTERISTICS AND FINISH

Level 1

Expressed joints

Visible PVC sheet joiners

Painted flat finish

Will follow the frame straightness

Level 2

Joints taped and set

Roll-on finish

Joints hidden behind coatings system

Joints may show through under standard lighting conditions

Not suitable for quality broad wall installation

Level 3

Joints taped and set

+ 2 mm trowel-on texture coating or polymer render

Joints not visible under normal lighting conditions

Joints may be visible under sidelight conditions (critical light)

Not recommended for broad wall applications on quality projects

Level 4

Joints taped and set

Polymer render over entire wall

+ 2 mm trowel-on texture coating or polymer render

Joints not visible under normal lighting conditions

Joints may be visible under sidelight conditions (critical light)

Not recommended for broad wall applications on quality projects

Level 5

Screeded reinforced cement render

Minimum 1 mm acrylic-based texture coating or membrane paint

No visible joints under any light conditions

Look and feel of rendered masonry

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We have seen that badly designed lighting can spoil the appearance

of a flat surface and that similar effects may also occur when gloss

paints are used. Gloss paint reflects light so that a blurred mirror

image of the light source is formed which is distorted by irregularities

in the surface. The irregularities become particularly noticeable when

the observer moves in relation to the surface just like an image in an

uneven mirror changes in shape or size when observed from

different positions.

For this reason gloss paint should not be applied to flat walls which

may be observed from a wide angle, or to upper surfaces or the

ceiling on which tell-tale reflections of the lighting units may be seen.

Its use on ceilings and long walls may therefore be undesirable but it

can probably be applied to short walls with reasonably good results.

The same effects seen with gloss paints occur to a lesser degree

with satin- or silk-finish paints. High-gloss paints can safely be used

on doors, woodwork and architraves which have plenty of detail to

distract the eye from the distorted reflections.

It must be emphasised that these considerations apply only where

the effect of a flat, featureless surface is the main requirement.

There are circumstances in which gloss paints may be desirable for

functional reasons, for example in kitchens, bathrooms or laundries,

in which case some loss in appearance of the surfaces may have to

be accepted.

G L O S S P A I N T O N F L A T S U R F A C E S

Page 25Gloss paint on flat surfaces

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If the decorative effects of expanses of flat, unbroken surfaces are to

be appreciated it must be recognised when the lighting is planned

that no building surface is perfectly flat. The aim in building is to

produce the appearance of flatness and with practical surfaces the

appearance of flatness can always be destroyed by glancing light.

This is not a serious difficulty in offices and factories lit in accordance

with the principles outlined in Australian Standard No. 1680: 1990;

however, in domestic situations where the code does not apply,

isolated lamps are often used and the following points should be

especially considered.

Glancing light from isolated sources must be avoided. Where

isolated lamps are used, they are best placed well below the level

of the ceiling, or above it in suitably recessed light fittings. Care

must be taken when placing lights close to walls. In decorative

interiors, valances or ‘cafe curtains’ may be used on windows

that reach ceiling height and narrow windows close to walls

should be curtained.

High-gloss paint should be avoided whenever the surface can be

seen from a wide angle. This precludes its use on ceilings and long

walls if an even appearance is required.

If the effect of a flat, unbroken surface is desired the painting and

illumination must be planned accordingly. If this is not done and

unsightly effects are obtained one cannot justly blame the lights, the

lining material or the paint. It is the way in which these elements have

been combined that is at fault.

R E C O M M E N D A T I O N S

Page 27Recommendations

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Page 40: Flat Surfaces

It is beyond the scope of this book to fully explore the technical

details relating to the design, construction, lining, plastering,

decorating and lighting of buildings. Moreover, these technical

details can change over time. So we have included various links to

industry bodies and company websites where the latest information

and standards can be obtained. Also listed are reference books that

contain useful and relevant information on these topics.

LINKSAssociation of Wall and Ceiling Industries,

<http://www.awci.org.au>

Boral Limited, <http://www.boral.com.au>

CSR Building Products, <http://www.csr.com.au>

James Hardie, <http://www.jameshardie.com.au>

BGC, <http://www.bgc.com.au>

Rockcote, <http://www.rockcote.com.au> – this website contains

information on all exterior and interior surface preparation and

finishing systems.

R E F E R E N C E S A N D L I N K S

Page 29References and links

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Illumination & decoration of flat surfacesPage 30

REFERENCE BOOKSAustralian Standard (1990) AS 1680: 1990 Code of Practice for

Interior Lighting and the Visual Environment. Standards Australia,

Sydney.

Australian/New Zealand Standard (2007) AS/NZS 2589: 2007

Gypsum Linings – Application and Finishing. Standards Australia,

Sydney.

Phillips RO (1999) Sunlight and Shade in Australasia. Sixth edition.

CSIRO Publishing, Melbourne.

Lechner N (2008) Heating, Cooling, Lighting: Design Methods for

Architects. Third edition. Wiley, New Jersey.

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