lighting analysis for pontypridd library
DESCRIPTION
Investigation into qualities of day and artificial light in the main bookshelf space of Library designTRANSCRIPT
Ligh
t as
a de
sign
tool
Hea
ther
Org
anTe
chno
logy
IKW
Sa2
June
090
0Ju
ne 1
200
The
spac
e st
udie
d he
re is
the
sect
ion
of th
e L
ibra
ry w
here
the
maj
ority
of t
he b
ooks
helv
es
are
loca
ted.
For
this
func
tion
I wis
hed
to c
reat
e a
di�u
sed
ambi
ant l
evel
of l
ight
ing,
but
with
sh
arpe
r ban
ds o
f lig
ht fr
om th
e so
uth
to d
enot
e th
e pa
ssin
g of
tim
e th
roug
h st
rate
gica
lly
plac
ed a
nd c
ontr
olle
d op
enin
gs.
The
maj
ority
of
the
faca
de re
ceiv
es s
outh
ern
light
(dire
ctly
fo
rwar
d in
thes
e re
nder
ings
) so
I pla
nned
to im
plem
ent s
hadi
ng in
to th
e de
sign
of t
he
open
ings
to d
i�us
e th
e lig
ht a
s it
ente
red
the
build
ing
and
also
con
trol
the
lux
leve
ls a
nd
glar
e w
ithin
the
spac
e.I w
ishe
d th
e sp
ace
to h
ave
a hu
man
sca
le a
ndfe
el w
arm
as
it is
like
the
hear
t of t
he L
ibra
ry,
whe
re th
e m
ajor
ity o
f the
sur
roun
ding
life
emin
ates
from
. The
dire
ct ra
ys o
f lig
ht p
rovi
deth
is li
tera
lly b
y w
arm
ing
the
surf
aces
, be
they
obje
ct o
r peo
ple,
whi
ch th
ey fa
ll up
on. T
his
war
mth
is a
lso
achi
eved
thro
ught
he
use
oftim
ber a
cros
s th
e ce
iling
as
som
e of
the
wal
ls,
espe
cial
ly b
ecau
se it
s ho
ney
colo
ur is
acc
entu
ated
furt
her b
y th
e su
nlig
ht.
Mar
ch 0
900
Mar
ch 1
200
Mar
ch 1
600
June
160
0
Dec
embe
r 090
0D
ecem
ber 1
200
Dec
embe
r 160
0
June
120
0
Daylight AnalysisHeather OrganTechnology IKWSa2
Light meter analysisThe initial light meter render takes into account both the mezzanine level and the double height space where the mezzanine stops. In the second image, the dimensions of the light meter are reduced to eliminate the white areas. The secondset of measurements are more accurate as they are calcuated at the correct height above the �oor.
Light meter gather 1
Light meter gather 2
The two qualities of light I aimed to achieve in the space (ambient and direct) could be interpreted as scalar and directional illumination. The scalar quality of light allows surfaces to be seen, but directional light adds de�nition and depth to them. I hoped to achieve both qualities of light as I didn’t want lots of strong light rays entering the space, however without any I felt the space could become �at.
Quantitatively, the lux levels I was aiming to create were between 600 and 800 lux, along with a daylight factor of 1. This is the reccommended level for reading and to illuminate the vertical spines of book or the shelves that they are on.
The light meter analysis from the 3D model of the space estimates the light levels that would be achieved at this particular time of day, in this case 1200 June 21 2011.
For example, in the darker blue area at the front of the mezzanine there is a gain of 150 lux of direct light and 600 lux of indirect light, which gives an overall lighting level witin the reccommended values. The daylight factor in the same space was 0.77, slightly below reccommendation.
Arti�cial Light AnalysisHeather OrganTechnology IKWSa2
The arti�cial lighting aims to achieve similar lighting e�ects and atmosphereas the controlled natural light during daylight hours. The description from ERCOof these suspended lights shows they create a di�used ambient light with sharper light falling on horizontal planes:
As seen in the two light meter renderings below, the light is dispersed evenly along the line of the bookshelves. The lights are suspended along the spacebetween shelves so as it is where the most direct light is needed to read the spines of the books and possibly �ick through them.
The 3D lighting model calculations of lux levels are in excess of what they should be, however the general pattern can still be used to assess the atmosphere created.
“What makes Starpoint pendant downlights special is their matt frosted glass cover. The shimmering surface is more than just a decorative e�ect: it di�uses a small proportion of the light and results not only in bright light on the horizontal surface, but also comfortable ambient brightness. The aluminium lampholder housing has a ribbed heat sink which e�ectively dissipates the heat of the low-voltage halogen lamp. ”
The tectonics of the scheme are based in invention and tell a story of the towns history in industry. The materials and their use relate to the railway which still remains an important connection to Cardi� and the rest of Wales. For this reason, the steels I beams, which are clad in Anthra Zinc, are exposed with the rest of the structure hung from them. This also resolves the problem of cold bridges which arises when wanting a column to be exposed on both the interior and exterior, or when between a column exposed on the exterior and a beam exposed on the interior.
The beams are not only structural as they also function aesthetically to carry rainwater collected on the roofs down to the water features around the internal courtyard space. As well as this they function as a light shelf - as the construction is hung approximately 100mm below them, di�used light can be let down through glazing of the same sectional width to illuminate the bookshelves below with a softer northern quality daylight, rather than the harsher sunlight gained from the southern aspect.
The glazing is sunk into the window sill to appear seamless and allow for crisper shadows in the internal spaces.
The frame construction allows for two layers of insulation, one between the I columns and the other between the wooden studs on the interior. The damp proof membrane seals over these insulative layers to keep water out of the wall, other than in the air gap on the exterior layer. There is no vapour barrier as the wood within the walls should be allowed to breathe, and this provides a small amount of natural ventilation through controlled leakage. This decreases the likelihood of problems from condensation and reduces the service costs of the building through ventilation. The U value of the wall and the glass covered collonade on the exterior side of this wall should be su�cient to stop the lack of vapour barrier from impacting on heat retainment.
This section of building sits upon a raft foundation, however this changes in other areas of the building due to proximity to the river and presumed reduced stability of the substrate.
Heather OrganTechnology IKWSa2
Detail Section
anthra zinc clad steel I beamsDPM
douglas �r timber studs
douglas �r cladding
screed
sand
concrete
double glazing
insulation
air gap
�nish