What is the Emden formula for head office overheads?

Emden formula: head office overhead and profit × (contract sum / contract period) × delay weeks. Calculates head office overhead contribution lost during prolongation. Alternative formulae: Hudson (uses contracted rate), Eichleay (US federal contracts).

What is the difference between prolongation and disruption?

Prolongation costs arise from extended time on site (additional site overheads, preliminaries). Disruption costs arise from loss of productivity on work executed at the same time as a delaying event (labour inefficiency). Both may be recoverable under JCT L&E if caused by a relevant matter.

JCT Loss and Expense Claim Estimate Calculator

Estimate JCT loss and expense claim quantum under clauses 4.20–4.26 JCT SBC: prolongation costs (site overheads), disruption costs (productivity loss), head office overheads (Emden/Hudson formula), and interest/finance charges.

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⚖ For informational purposes only. Not legal advice. Consult a licensed attorney for your specific situation.

How to Use

Enter the values for the scenario you are assessing. Estimate JCT loss and expense claim quantum under clauses 4.20–4.26 JCT SBC: prolongation costs (site overheads), disruption costs (productivity loss), head office overheads (Emden/Hudson formula), and interest/finance charges. Use the jct loss & expense result to inform your calculation.

JCT Loss and Expense Claim Estimate Calculator

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Frequently Asked Questions

What is the Emden formula for head office overheads?

What is the difference between prolongation and disruption?