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Deck Calculator - Stumps, Bearers, Joists and Boards with Individual + Total Costs and Connections (fasteners)

Deck Material List and Cost Calculator Material List and Costs
Jump To: StumpsBearersJoistsBoards

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Deck Length
Deck Width

Stump Width
Stump Height
Stump Centres
Stump Set In
Footing Diam:
Footing Depth

Board Width
Board Thick
Gaps set to fit full width boards, at or larger than Min. For exact gap see Board Fit Options
Min Board Gap
Centres Adjusted to Fit Centres Adjusted to Fit Evenly
Bearer Thickness
Bearer Depth
Requires longer stumps to maintain deck height
Bearer Set In = Joist Overhang from OUTSIDE of bearer to end of joist (edge of deck)
Bearer Set In Inner
From OUTSIDE of bearer to end of joist (edge of deck)
Bearer Set In Outer
Bearer Centres

Joist Thickness
Joist Depth
Joist Centres
End Joist Set In allows Deck Board Overhang at each end of deck
End Joists Set In

Ground Fall in Width


Deck plan with full dimensions - Stumps, Bearers, Joists, Boards, Timber Costs

Enter Linear Costs

Correct Diagonal to Square Deck =
Use correct diagonal to square deck.
When both diagonals = deck is square.

Total Deck Height   (Stump base to board top)

Deck Area =

Stumps Top ↑

STUMP Running set-out points along Deck ~ along Bearer (to near side of each stump)

Deck Stumps and Bearers diagram

STUMP Running set-out points across Deck ~ along Joist from Inside (to near side of each stump)

Fall in Width

Deck Stumps and Joists diagram

Bearers Top ↑

BEARER Running set-out points, across Deck ~ along Joist from inner side
(to near side of each bearer)

Deck Bearers diagram

Joists Top ↑

JOIST Running set-out points along Bearer (to near side of each joist)

Deck Joists diagram

Deck Boards Top ↑

Mark Every Boards (Red).  

BOARD Running set-out points.

Deck Joists and Boards diagram

Tips for Laying Deck Boards Read this Forum Thread about Tips for Laying Deck Boards

Set Length Boards
Board Estimate Only Estimate only - Allows wastage calculated from board length and joist spacings only.

Enter Costs per Linear Metre and % waste to calculate Total Cost

Stumps + % Waste @ $ m
Bearers + % Waste @ $ m
Joists + % Waste @ $ m
Boards + % Waste @ $ m

Enter cost per linear metre and wastage % for Stumps, Bearers, Joists and Boards to Calculate individual and Total Costs. Linear metres and cost are auto updated when the deck is re-calculated, with individual costs for stumps, bearers and joists displayed in each section. Hit + and - buttons to open or close spacing, re-calculating the deck to find how different spacing options effect cost and materials.

Out of Square If your deck is slightly out of square (different widths), calculate results for both widths, and set out each end to suit. If necessary, adjust number of deck boards to match in both calculations, and see if different board gaps at each end of deck are acceptable, compared to equal gaps and cutting the last board at an angle. Use the widest dimensions for linear quantities.

DON'T BREATH THE DUST If you're cutting blocks, concrete, stone or ANYTHING and there's DUST - DON'T TAKE THE RISK
Don't cut it, or cut it wet so there's NO DUST - Silicosis Sucks
And if you're cutting wet, wear a mask - theres dust in the spray too!

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