<s>
The	O
Industry	B-Application
Foundation	I-Application
Classes	I-Application
(	O
IFC	O
)	O
is	O
a	O
CAD	O
data	O
exchange	O
data	O
schema	O
intended	O
for	O
description	O
of	O
architectural	O
,	O
building	O
and	O
construction	O
industry	O
data	O
.	O
</s>
<s>
It	O
is	O
an	O
object-based	O
data	O
schema	O
with	O
a	O
data	B-Application
model	I-Application
developed	O
by	O
buildingSMART	B-Application
(	O
formerly	O
the	O
International	O
Alliance	O
for	O
Interoperability	O
,	O
IAI	O
)	O
to	O
facilitate	O
interoperability	O
in	O
the	O
architecture	O
,	O
engineering	O
and	O
construction	O
(	O
AEC	O
)	O
industry	O
,	O
and	O
is	O
a	O
commonly	O
used	O
collaboration	O
format	O
in	O
Building	B-Architecture
information	I-Architecture
modeling	I-Architecture
(	O
BIM	B-Architecture
)	O
based	O
projects	O
.	O
</s>
<s>
In	O
2017	O
the	O
Finnish	O
state-owned	O
facility	O
management	O
company	O
Senate	O
Properties	O
started	O
to	O
demand	O
use	O
of	O
IFC	O
compatible	O
software	O
and	O
BIM	B-Architecture
in	O
all	O
their	O
projects	O
.	O
</s>
<s>
Also	O
the	O
Norwegian	O
Government	O
,	O
Health	O
and	O
Defense	O
client	O
organisations	O
require	O
use	O
of	O
IFC	O
BIM	B-Architecture
in	O
all	O
projects	O
as	O
well	O
as	O
many	O
municipalities	O
,	O
private	O
clients	O
,	O
contractors	O
and	O
designers	O
have	O
integrated	O
IFC	O
BIM	B-Architecture
in	O
their	O
business	O
..	O
</s>
<s>
A	O
further	O
name	O
change	O
occurred	O
in	O
2005	O
,	O
and	O
the	O
IFC	O
specification	O
is	O
now	O
developed	O
and	O
maintained	O
by	O
buildingSMART	B-Application
.	O
</s>
<s>
IFC-SPF	O
is	O
a	O
text	O
format	O
defined	O
by	O
ISO	O
10303-21	O
(	O
"	O
STEP-File	O
"	O
)	O
,	O
where	O
each	O
line	O
typically	O
consists	O
of	O
a	O
single	O
object	O
record	O
,	O
and	O
having	O
file	O
extension	O
"	O
.ifc	B-Application
"	O
.	O
</s>
<s>
IFC-XML	O
is	O
an	O
XML	B-Protocol
format	O
defined	O
by	O
ISO	O
10303-28	O
(	O
"	O
STEP-XML	O
"	O
)	O
,	O
having	O
file	O
extension	O
"	O
.ifcXML	O
"	O
.	O
</s>
<s>
This	O
format	O
is	O
suitable	O
for	O
interoperability	O
with	O
XML	B-Protocol
tools	O
and	O
exchanging	O
partial	O
building	O
models	O
.	O
</s>
<s>
IFC-ZIP	O
is	O
a	O
ZIP	B-General_Concept
compressed	O
format	O
consisting	O
of	O
an	O
embedded	O
IFC-SPF	O
file	O
or	O
IFC-XML	O
file	O
and	O
having	O
file	O
extension	O
"	O
.ifcZIP	O
"	O
.	O
</s>
<s>
IFC-RDF	O
is	O
a	O
XML-based	O
semantic	O
data	O
format	O
that	O
uses	O
RDF	O
and	O
is	O
expressed	O
in	O
the	O
ifcOWL	O
ontology	O
.	O
</s>
<s>
ifcJSON	O
uses	O
JSON	B-General_Concept
,	O
a	O
modern	O
format	O
often	O
used	O
by	O
web	O
applications	O
.	O
</s>
<s>
IFC-SPF	O
is	O
in	O
ASCII	B-Protocol
format	O
which	O
,	O
while	O
human-readable	O
,	O
suffers	O
from	O
common	O
ASCII	B-Protocol
file	I-Protocol
issues	O
,	O
in	O
that	O
file-sizes	O
are	O
bloated	O
,	O
files	O
must	O
be	O
read	O
sequentially	O
from	O
start	O
to	O
finish	O
,	O
mid-file	O
extraction	O
is	O
not	O
possible	O
,	O
files	O
are	O
slow	O
to	O
parse	O
,	O
and	O
definitions	O
are	O
non-hierarchical	O
.	O
</s>
<s>
In	O
addition	O
to	O
ifcXML	O
and	O
ifcZIP	O
,	O
modern	O
data	O
formats	O
include	O
RDF/XML	O
or	O
Turtle	O
(	O
using	O
the	O
ifcOWL	O
ontology	O
)	O
,	O
ifcJSON	O
(	O
JavaScript	B-General_Concept
Object	I-General_Concept
Notation	I-General_Concept
,	O
broadly	O
available	O
)	O
and	O
ifcHDF5	O
(	O
Hierarchical	B-Application
Data	I-Application
Format	I-Application
v5	O
,	O
binary	O
)	O
.	O
</s>
<s>
In	O
2020	O
,	O
buildingSmart	B-Application
had	O
two	O
JSON	B-General_Concept
projects	O
underway	O
:	O
ifcJSON	O
v4	O
(	O
a	O
direct	O
mapping	O
from	O
EXPRESS-based	O
IFC	O
v4	O
)	O
and	O
ifcJSON	O
v5	O
,	O
plus	O
a	O
research	O
project	O
experimenting	O
with	O
turning	O
IFC	O
into	O
a	O
binary	O
format	O
.	O
</s>
<s>
IFC	O
defines	O
an	O
EXPRESS	B-Application
based	O
entity-relationship	B-Architecture
model	I-Architecture
consisting	O
of	O
several	O
hundred	O
entities	O
organized	O
into	O
an	O
object-based	O
inheritance	O
hierarchy	O
.	O
</s>
<s>
Rooted	O
entities	O
derive	O
from	O
IfcRoot	O
and	O
have	O
a	O
concept	O
of	O
identity	O
(	O
having	O
a	O
GUID	O
)	O
,	O
along	O
with	O
attributes	O
for	O
name	O
,	O
description	O
,	O
and	O
revision	B-Architecture
control	I-Architecture
.	O
</s>
<s>
'	O
Body	O
 '	O
indicates	O
a	O
3D	O
shape	O
which	O
may	O
be	O
represented	O
by	O
B-rep	B-Algorithm
,	O
NURBS	B-Algorithm
,	O
Constructive	O
Solid	O
Geometry	O
(	O
CSG	O
)	O
,	O
or	O
swept	O
profiles	O
.	O
</s>
<s>
Projects	O
support	O
revision	B-Architecture
control	I-Architecture
where	O
any	O
IfcRoot-based	O
entity	O
has	O
a	O
unique	O
identifier	O
and	O
may	O
be	O
marked	O
as	O
added	O
,	O
modified	O
,	O
deleted	O
,	O
or	O
having	O
no	O
change	O
.	O
</s>
