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Deck fixings Calculator

Estimate screws from board-to-joist intersections.

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How to use this calculator

Your measurements

Enter your project values to update the estimate.

Item name (optional)

View your estimate

Set locations to your total intersections and fixings per location to the chosen fastening system.

YOUR ESTIMATE

Fasteners to buy

Base quantity80

Packs to buy1

Whole quantities are rounded up.

PLAN YOUR PROJECT COST

Pricing calculator

Use your supplier’s rate or enter a quoted total. Save each estimate to your project and print everything together.

What are you pricing?

Price is per

Price (optional)

Currency label

Your selected quantity already includes any allowance shown in that result. Check whether you are pricing individual items or whole packs. Delivery, tax and labour are not added automatically. A quoted total applies only to this saved calculation.

Deck fixings Calculator: measuring notes and method

Count board-to-joist intersections

Multiply the number of board rows by the supporting joist positions they cross, adjusting for the actual layout. Use that intersection count as locations, then enter the fixings required at each.

Separate field fixings from other hardware

Starter clips, edge clips, joints, fascia screws and framing connections may use different products. Save them as separate items; the pack result applies only to the fixing entered here.

Formula

Fixings = locations × fixings per location × (1 + waste ÷ 100), rounded up. Packs are rounded up separately.

Worked example

Illustrative values match Reset example and stay fixed when you edit the calculator.

Starting-value worked example

Pieces / fixing locations: 20
Fixings per piece / location: 4
Fixings per pack: 100
Waste allowance: 10 %

Fasteners to buy: 88

Follow the calculation

Base fixings = 20 × 4 = 80.
Multiply by 1.1 and round up to whole fixings. Divide that count by 100 per pack and round up again.

Reviewed 19 October 2026. How calculations are checked · Report a correction

Related calculators

Decking CalculatorEstimate full-length board rows across a deck.Deck joists CalculatorEstimate joists from a specified centre spacing.Deck coating CalculatorEstimate deck oil, stain or coating from measured surface area and product coverage.

PRACTICAL READING

Understand the inputs. Check the order.

Measurement methods and worked examples to use alongside this calculator.

Count deck boards across the width and cuts along the lengthBoard width, gaps and stock lengths create two separate quantity checks.
Estimate deck fixings and finish from the selected layoutCount fixing locations and coated faces separately from the deck footprint.
Build a measurement register you can check laterRecord where each number came from before it becomes part of a material order.
Choose an allowance you can explainSeparate measured quantity, cutting loss and uncertainty instead of adding an automatic percentage everywhere.

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