PBS: prefabricated shells that become the formwork and the finish
PBS (Prefabricated Building Shell) uses thin fibre-reinforced concrete shells as permanent formwork for columns, beams, walls and slabs. The shells are set on site with the rebar inside, then filled into one monolithic RC structure.
Cangkang pracetak + perakitan di lokasi + pengecoran monolitik
01
Factory shells
Fibre-reinforced boards formed into column, beam, wall and slab shells.
02
Pengiriman
Light shells, no curing on site.
03
Assembly
Shells placed around rebar cages.
04
Pour
Concrete fills the shells; the board bonds.
05
Finish
Surfaces ready for putty and paint.
Desain
Who designs a PBS building?
Item
Responsibility
Basis
Structure (members, rebar)
Your engineer, as a normal RC frame or wall structure
Local concrete code (GB 50010, ACI 318, EN 1992)
Shell layout and joints
GGSteel
PBS design atlas and application specification
Pour sequence and lift heights
GGSteel with your contractor
Shell capacity against fresh concrete pressure
Connections between shells
GGSteel
PBS details
The shell is formwork, not structure. Strength comes from the cast-in-place concrete and rebar, so the structure is checked like any RC building. That is why local approval is usually simpler than for a new precast system.
From our engineers
Three site points that decide quality
Pour in lifts. Fresh concrete pushes on the shell. Columns and walls are poured in lifts at the rate in our method statement, not in one go.
Set-out first. Shells are placed to grid lines and levels before the rebar is closed; once filled, position cannot be corrected.
Protect the face. The shell is the finish. Chips from handling are repaired before the pour.
Product range
PBS shells by element
Column and beam shells
Permanent formwork for RC columns and beams.
Shear wall shells
Double-skin wall shells filled on site.
Slab and haunch shells
Floor deck and haunched slab elements.
Benefits
Faster, cleaner, comparable cost
Programme
Design time saved 50%, construction time saved 30%.*
Biaya
About equal to cast-in-place; 10%+ lower than precast concrete by project size.*
Fewer trades
No formwork removal, no plastering, fewer props.
Kualitas
Factory-made surfaces, insulation, sound and moisture performance.
*GGSteel project comparisons.
PBS suits
RC frame and shear wall buildings: housing, schools, offices
Precast speed without heavy precast lifting
Sites short of formwork labour
Consider alternatives when
Pure steel frames, where truss deck and ALC suit better
Markets where the authority requires testing of any new formwork system