CupLock Calculator

Two ways to start#

Open it from your project#

If the project, building and slabs are already in PlyMax, don't type their numbers again. Open the calculator from where the data lives and it arrives filled in.

The calculator then fills in:

You can also link by hand on the calculator page: under Link to Existing Building, choose the Project, the Building and the Floor / Slab. Each floor in the list shows its area and clear height, and whether it already has CupLock materials.

Run a calculation#

1. Check the slab zone

   Every calculation starts with one slab zone, Main Flat Slab. Rename it if you like. Enter the Clear Height (floor to slab soffit, in metres), the Area in m² and the Slab Thickness in mm. If you opened the calculator from your project, these are already filled in. The Live Load follows from the thickness (BS 5975) and can't be edited.

2. Pick how the standards stack

   Under the height fields, the calculator recommends the standards that make up each leg, e.g. Recommended: 2.5m. Open the list to see every combination that fits, ranked from Optimal to Not Recommended. Fewer pieces means fewer joints: a stiffer leg that is faster to erect. Click an option to use it.

   

   Ledger Levels is worked out from the height. Switch it to Manual only if your method statement calls for a set number of levels.

3. Choose the materials

   Pick the Sheathing, Secondary Beam and Main Beam. They set the build-up between the U-head and the slab (the soffit height), and they are what the safe-grid check uses. The lists come from your beam library, the same one the Falsework Calculator uses.

4. Click Suggest Safe Grid

   The calculator sizes the grid for this slab and shows the load breakdown, a PASS or FAIL, the secondary and main beam spacings, the shoring grid, and the load on each leg against its 3.4 t capacity.

   

   Under Safe Grid Options, pick any grid that suits the ledgers you have. Every option has passed the checks; the bar shows how much of the leg capacity it uses.

5. Click Calculate MTO

   The results open on the right, on the Materials tab.

Input reference#

Slab zone

Advanced options

Available sizes, listed at the bottom of the input panel:

Manual grid#

To use a grid of your own, switch to Manual Grid and pick Grid X and Grid Y from the ledger lengths, then enter the Beam Spacing (secondary beams, in metres). The calculator checks it straight away.

Zones and beams#

A floor is rarely one flat slab. Add more zones under the zone list:

• + Slab Zone: another area with a different height, thickness or grid, e.g. a double-height lobby. It starts with the last zone's values. The total area of all slab zones is shown next to the buttons.
• + Beam Zone: the props under a downstand beam, measured by length instead of area.

Beam zones

Enter the beam's Total Length, Beam Width and Beam Depth (D). The calculator works out the Drop Below Slab (depth minus slab thickness) and, in Auto, the Clear Height to Soffit under the beam (the slab's clear height minus the drop). It also suggests how many Prop Rows to put across the beam's width; use the − / + buttons to change it.

The sketches show how the ledgers sit along the beam. They are for setting out only; they don't change the quantities.

Reading the results#

At the top: the project, date, safety margin and number of zones, then four totals: Standards, Ledgers, Beams (LM) in linear metres, and Accessories. Below them, three tabs.

Materials

Every item, grouped into Standards, Ledgers, Beams and Accessories. Net Qty is what the design needs; Wastage is your safety margin; Order Qty is what to order. With several zones, switch between each zone and the grand total.

3D View

The shoring as built, with a legend for each component. Drag to rotate, scroll to zoom, and click Reset View to start again. The panel on the right breaks down the height: soffit build-up, U-head, standards and P-head.

Grid

Standards along each side, total leg locations, the area actually covered (rounded up to whole bays) and a top-view dot plan of the legs.

Assign to your floors#

When the calculator is linked to a building, the result can go straight onto the building's material list. Each item needs to match an item in your material library first.

1. Map any unmatched items

   If some items don't match your library, a yellow notice lists them. Click Configure materials and pick your library item for each calculator component, or click Auto-match remaining. Click Save mapping. The calculator remembers it for next time.

   

2. Click Assign to Floor

   The button names the floor, e.g. Assign to Floor 1 — Floor 1 Slab. PlyMax then suggests other floors the same quantities fit.

   

   Group	Meaning	Ticked?
   Calculated floor (locked)	The floor you calculated.	Always
   Perfect match	Same clear height (±0.1 m), area (±5%) and thickness (±5 mm).	Yes
   Same height — area or thickness differs	Same legs, but the counts would differ.	No. Tick only if you accept that
   Different clear height — needs own MTO	Different standards. Click Calculate → to run that floor.	No
   No clear height set	PlyMax can't compare it. Check before ticking.	No

3. Click Assign to N floors

   The items are added to each floor on the building's Materials page, and those floors show as covered (F1 ✓). Use Back to Materials at the top of the calculator to return.

   Assigning adds, it doesn't replace

   Assigning again creates a second set of items. Remove the old CupLock MTO from the floor first.

Save and export#

• Save Calculation keeps the inputs and results. Open them again from Calculation History at the top of the page, where you can search, sort and delete.
• Excel downloads the material take-off as a workbook to send to your supplier or store.
• Reset clears the zones and settings back to the defaults.

Plans and limits#

On the free trial you get 5 MTO calculations a month; a bar above Calculate MTO shows how many are left. Each click on Calculate MTO counts as one. Suggest Safe Grid doesn't count. Paid plans have no monthly limit.

Troubleshooting#