POSI-JOIST
STANDARD DETAILS
VERSION 2, 25/11/02.
PSD27
Posi-web over
bearing by min
15mm
Service Void
100mm Mineral
wool insulation
quilt 23kg/m2.
2 no 30 x 200mm GMS
Straps at 1200mm centres.
Bead of sealent applied
to floor deck prior to fixing
19mm plasterboard plank.
Mineral wool
cavity barrier.
Floor Comprising:22mm T & G Chipboard on
19mm Plasterboard Plank on
47x75mm Resilient floor batten
at 600mm centres on
18mm T & G Chipboard.
All T & G edges glued.
SE
RV
IC
EV
OI
D
47x 89 Continuous Pack
47x 89 Packs
between joists.
2
ap 00
pro
x
First Posi-Joist beam
set back from wall
by approx 200mm
Plasterboard
Posi-Joists
noggins
Parallel to wall.
Ring Beams in
solid timber or LVL.
Posi-Joists
Bearing on wall.
Ceiling (not shown) comprising:2 Layers 15mm Gyproc Fireline Board on 16mm resilient bars at 400mm
centres. First layer fixed with 38mm Gyproc screws at 230mm centres.
Second layer fixed with 60mm Gyproc screws at 230mm centres.
Staggered with first layer screws.
Lay Firleline board in echelon pattern with staggered joints.
TYPICAL TIMBER FRAME COMPARTMENT
FLOOR / PARTY WALL DETAIL WITH
SERVICE VOID
CONTENTS
PSD01 - Posi-Joist to girder.
PSD02 - Bottom chord fixing (with noggins).
PSD03 - Bottom chord fixing (with continuous estraint).
PSD04 - Top chord fixing to timber frame.
PSD05 - Masonry hanger (with noggins).
PSD06 - Masonry hanger ( with continuous ledger).
PSD07 - Bottom chord built into masonry.
PSD08 - Top chord built into masonry.
PSD09 - Continuous joist through masonry.
PSD10 - Top chord fixing to steel.
PSD11 - Internal bearing.
PSD12 - Partitions parallel to floor.
PSD13 - Partitions above and parallel to floor.
PSD14 - Maximum duct sizes.
PSD15 - Edge closure.
PSD16 - Staircase opening 1.
PSD17 - Staircase opening 2.
PSD18 - Narrow opening 1.
PSD19 - Narrow opening 2.
PSD20 - Strongback 1.
PSD21 - Strongback 2.
PSD22 - Strongback bridging.
PSD23 - Strongback splice.
PSD24 - Horizontal restraint fixed to strongback.
PSD25 - Horizontal restraint.
PSD26 - Timber frame compartment wall/party wall.
PSD27 - Timber frame compartment wall/party wall (with service void).
PSD01
Posi-web over
bearing by min
15mm
PSD26
100mm Mineral
wool insulation
quilt 23kg/m2.
Simpson L70 angles or similar
as specified by design
2 no 30 x 200mm GMS
Straps at 1200mm centres.
Mineral wool
cavity barrier.
Floating Floor Comprising:18mm T & G Chipboard on 19mm Plasterboard Plank
on 25mm Fibreglass Slab on 18mm T & G Chipboard.
All T & G edges glued, and 19mm plank bonded to
chipboard with dabs of Gyproc sealant at 300mm
centres. Joints between chipboard and plasterboard
to be staggered and board direction reversed.
Bead of sealent applied
to floor deck prior to fixing
19mm plasterboard plank.
47x 89 Continuous Pack
47x 89 Packs
between joists.
Simpson LBV or
Cullen OWF/
OWT hangers.
Bottom member of posi
to be notched over bottom
flange of hanger
2
ap 00
pro
x
First Posi-Joist beam
set back from wall
by approx 200mm
Plasterboard
Posi-Joists
noggins
Parallel to wall.
Ring Beams in
solid timber or LVL.
Posi-Joists
Bearing on wall.
Ceiling (not shown) comprising:2 Layers 15mm Gyproc Fireline Board on 16mm resilient bars at 400mm
centres. First layer fixed with 38mm Gyproc screws at 230mm centres.
Second layer fixed with 60mm Gyproc screws at 230mm centres.
Staggered with first layer screws.
Lay Firleline board in echelon pattern with staggered joints.
POSI-JOIST TO GIRDER DETAIL
TYPICAL TIMBER FRAME COMPARTMENT
FLOOR / PARTY WALL DETAIL
PSD25
PSD02
35 x 97 C16 twice nailed to brace using
3.1 x 75mm long galvanised wire nails
Strap fixed with a minimum of four
fixings of which at least one is to
be over the third joist.
HORIZONTAL RESTRAINT
STRAP DETAIL
47x72 top chord restraint
fixed between beams
Head binder
BOTTOM CHORD FIXING
TO TIMBER FRAME
(with restraint noggins)
PSD03
PSD24
Continuous 47x72 top chord
restraint fixed over ribbon block.
Twice nailed to brace using
3.1 x 75mm long galvanised wire nails
Strap fixed with a minimum of four
fixings of which at least one is to
be over the third joist.
Head binder
BOTTOM CHORD FIXING
TO TIMBER FRAME
(with continuous restraint)
HORIZONTAL RESTRAINT
STRAP FIXED TO STRONGBACK
PSD04
PSD23
38x75 (min) blocks twice nailed to top and bottom
members and twice nailed to brace using 3.1 x 75mm
long galvanised wire nails
Posi-web over
bearing by min
15 mm
47x89 Packing piece
35 x D x 1200mm long splice fixed with 10 no 3.1 x 75mm
galvanised wire nails each side of splice,
nailed through and clenched over on far side
35 x D strongback, see table for depths.
WEB
SIZE
PS-8, PS-9 & PS-10
PS-210, PS-14 & PS16
STRONGBACK
DEPTH
100
Ring beam
(size to suit)
Max 6mm gap
40x47 Continuous
plasterboard noggin
150
STRONGBACK SPLICE
TOP CHORD FIXING
TO TIMBER FRAME
PSD22
PSD05
47x72 top chord restraint
fixed between beams
Twice nailed to brace using
3.1 x 75mm long galvanised wire nails
Position strongbacks tight
to underside of top chord.
Minimum bearing determined by design
(choose correct hanger for load, bearing width
and courswork level of hanger bearing flange)
MASONRY HANGER DETAIL
STRONGBACK BRIDGING
(webs with built in verticals)
PSD21
PSD06
Continuous 47x72 ledger
fixed over ribbon block.
Twice nailed to brace using
3.1 x 75mm long galvanised wire nails
Position strongbacks tight
to underside of top chord.
Minimum bearing determined by design
(choose correct hanger for load, bearing width
and courswork level of hanger bearing flange)
INSERT STRONGBACK THROUGH JOISTS
BEFORE FIXING JOISTS. IT CANNOT BE
INSTALLED AFTER JOISTS HAVE BEEN FIXED.
STRONGBACK DETAIL
(webs with built in verticals)
Fix at a maximum of 4.0 metre centres.
MASONRY HANGER DETAIL
(continuous ledger)
PSD07
PSD20
Blockwork to continue
between beams
to provide restraint
38x75 (min) blocks twice nailed to top and bottom
members and twice nailed to brace using 3.1 x 75mm
long galvanised wire nails
Position strongbacks tight to the
underside of top chord.
(DTLR Robust Detail For Thermal
Bridging should be observed)
35mm x D strongback, see table for depth
WEB
SIZE
PS-8, PS-9 & PS-10
PS-210, PS-14 & PS16
STRONGBACK
DEPTH
100
150
INSERT STRONGBACK THROUGH JOISTS
BEFORE FIXING JOISTS. IT CANNOT BE
INSTALLED AFTER JOISTS HAVE BEEN FIXED.
BOTTOM CHORD BUILT
INTO MASONRY
STRONGBACK DETAIL
Fix at a maximum of 4.0 metre centres.
PSD19
PSD08
Continuous 47x72 ledger
fixed to wall.
Simpson L70 angles
or similar as specified
by design
Beam (depth to suit)
slotted through girders
Packing piece to
pick up ceiling
Max 6mm gap
(DTLR Robust Detail For Thermal
Bridging should be observed)
NARROW OPENING
TOP CHORD BUILT
INTO MASONRY
PSD09
PSD18
Solid timber block with
grain parallel to span
Simpson L70 angles or similar
as specified by design
Simpson LBV or
Cullen OWF /
OWT hangers
(DTLR Robust Detail For Thermal
Bridging should be observed)
CONTINUOUS JOIST
THROUGH MASONRY
Trimmer to be notched
over bottom flange
of hanger
NARROW OPENING
PSD17
Posi-web over
bearing by
15mm min
Simpson L70 angles or similar
as specified by design
PSD10
Posi-web over
bearing by
15mm min.
47x89 Noggins
between top chords
Simpson LBV or
Cullen OWF /
OWT hangers
Timber plate fixed
to top of steel
Solid timber or
LVL trimmer
depth to suit
Trimmer to be notched
over bottom flange
of hanger
Max 6mm gap
Timber pack fixed to
beam (size to suit)
STAIRCASE OPENING
TOP CHORD FIXING
TO STEEL
PSD16
PSD11
Simpson L70 angles or similar
as specified by design
Simpson LBV or Cullen
OWF / OWT hangers
Bottom member of posi
to be notched over bottom
flange of hanger
INTERNAL BEARING
STAIRCASE OPENING
PSD15
PSD12
Wall panel skew nailed through onto
noggin with a min of 2 no 3.35 dia
galvanised wire nails, length to suit.
35mm Prefabricated edge closure
Pre-faced with plywood with 20mm lap
at the top edge.
Noggin nailed down onto wall
panel as above.
Simpson
Z35N clips.
50
min
Edge closure to be supplied to site 4.8m long
and cut on site as required.
EDGE CLOSURE DETAIL
38x89 C16 (min) noggins
at max 600mm centres
NON-LOADBEARING PARTITIONS
PARALLEL TO FLOOR BEAMS.
PSD14
PSD13
Wall panels skew nailed through onto
noggins with a min of 2 no 3.35 dia
galvanised wire nails, length to suit.
W
Purpose made noggins
at max 600mm centers.
NON-LOADBEARING PARTITIONS
ABOVE AND PARALLEL
TO FLOOR BEAMS.
RECTANGLE DEPTH
POSI
STRUT
SIZE
W
PS-8
108
105
95
270 180 90
PS-9
134
130
115
310 240 180 100
PS-10
159
150
135
320 270 210 160 80
PS-210
210
190
155
350 310 260 210 160 110 70
PS-14
286
250
200
490 440 390 350 300 250 200 160 110 60
PS-16
324
275
220
510 470 430 390 340 300 260 220 170 130 90
CIRCLE
SQUARE 50
DIA
75 100 125 150 175 200 225 250 275 300
RECTANGLE WIDTH
-
-
-
-
-
INSERT LARGE SERVICES THROUGH JOISTS
BEFORE FIXING JOISTS. IT MAY NOT BE
POSSIBLE AFTER JOISTS HAVE BEEN FIXED.
MAXIMUM DUCT SIZES
-
-
-