Beam + One-Way SlabTraditional deep beams · 6–12 m
Waffle / RibbedTwo-way ribs · 9–14 m
Slab + JoistWide-spaced joists · 6–12 m
Precast HollowcoreProduct table · 6–12 m
Perimeter bays carry markedly more steel than interior bays — a whole floor plate is a mix of both.
Column size is computed from the axial load and fed back into the slab’s punching check. Leave blank unless you need to force a size.
Structural System
Post, Beam & PanelCLT one-way, beam-to-beam
Beam, Purlin & PanelPurlins carry thinner CLT
Point SupportCLT flat plate, no beams
Load-Bearing CLT WallsCLT walls + CLT floors
LWF HybridCLT floors on LWF stud walls
Grid Size
6.0
6.0
2
Building Parameters
8
3.2
Share of timber that receives the gypsum above; the rest is sized fully exposed. Panel sizing here uses the ENCAPSULATED condition; the blend drives the take-off intensity sent onward.
Loading
Other Dead Loads
Serviceability
Total Intensity
-
m³/m² GFA
Timber Cost
-
CLT Panel
-
Beams / Purlins
-
Columns / Walls
-
Grid Size
-
Floor Depth
-
Volume by Member-
Member Sizing
Member
Type
Size (mm)
Grade
Span (m)
Vol (m³/m²)
Governing
LWF Hybrid is limited to 6 storeys per NBC Part 3. Select a different system or reduce storey count.
Code Checks (CSA O86-19 / NBC 2020)
Fire Resistance (CSA O86-19 Annex B)
Column Load Accumulation
3 groups
Design Calculations (CSA O86-19 / NBC 2020)
Batch Permutation Generator
All valid system × storey × grid × FRR combinations. Click row to spot-check.
Refine Around:-
Click any row in the table or point on the chart, then click Refine to generate fine-grained grids around that solution.
FRR:System:
3.0 - 9.6m (10-31ft)
3.0 - 9.6m (10-31ft)
#
System
St
X (m)
Y (m)
Area
FRR
Panel
Beam
Column
m³/m²
$/m²
$/ft²
GL%
CLT%
System Class Summary (avg by system x storeys x FRR)
System
Storeys
FRR
Count
Avg m³/m²
Min m³/m²
Best Grid (int)
Avg $/m² ($/ft²)
Min $/m² ($/ft²)
Best Grid ($)
Avg Panel
Avg DW m²/m²
Reference Data
Material Intensity by Building Typology (m³/m²)
Building Type
Storeys
FRR
Base (Whirlwind Consultants DB)
Computed
Δ Avg
Primary System
Low
Avg
High
Low
Avg
High
Material Intensity by Structural System Type (m³/m²)
Structural System
Base Modifier
Base GL%
Computed Modifier
Computed GL%
Δ
Notes
Base values from Whirlwind Consultants database (200+ MT projects, report Section 2.4.2). Computed values use current Grid Sizer settings and material costs. Click "Compute from Batch Data" to run a comprehensive sweep and populate the Computed columns.
Material Properties
CLT LAYUPS (CSA O86-19)
Plies
t (mm)
Layup
EIeff
GAeff
Mr
Vr,rs
kPa
Material Cost Rates
$420
$250$900
$2300
$1,400$3,500
$4000
$2,000$6,000
$1650
$800$2,500
+10%
0%+40%
95%
80%100%
Members sized to this utilisation limit. 85% recommended for preliminary design.
Batch filter: Only results where the CLT panel governing check (bending or shear) is above 85% utilisation are shown. Under-utilised panels indicate a thinner panel would work, meaning the grid is not optimised for that system.
$10/m²
$6$18
$800
$400$1,200
$5/kg
$3$8
$1000
$600$1,500
System Parameters
65%
Percentage of grid perimeter with CLT shear walls. Higher = more CLT volume.
Specified product density — V 470, E 480 kg/m³. Drives BOTH gravity self-weight and vibration mass. Follows the grade unless moved.
500
Deflection Criteria
Deflection criterion is set in Serviceability on the main panel.
Batch Generator Limits
0.6
Results above this intensity are excluded from batch output.
10m²
Cost rates are applied to m³/m² intensities to estimate structural timber cost. Rates exclude installation, connections, finishes, and topping. Honeycomb wall % affects CLT volume in wall systems only. Other parameters affect structural sizing and will require re-running the batch generator.
