Construction Delay Claims: What Site Managers Need to Know

Delays are an unavoidable part of construction. Bad weather, design changes, late information, material shortages, and subcontractor failures all conspire to push completion dates further and further back. What matters is not whether delays happen, but how you manage them, document them, and, when necessary, turn them into legitimate contractual claims. This guide explains the fundamentals of delay claims from a site manager's perspective.

Understanding Delay in Construction Contracts

Most UK construction contracts, whether JCT, NEC, or bespoke, distinguish between two fundamentally different types of delay:

• Excusable delay - caused by events that are not the contractor's fault and which entitle them to an extension of time (EOT). Examples include exceptionally adverse weather, client-caused delays, and changes to the works
• Inexcusable delay - caused by the contractor's own failings, such as poor planning, insufficient resources, or subcontractor defaults. These delays do not entitle the contractor to additional time and may result in liquidated damages being applied

The distinction matters enormously. An extension of time protects the contractor from liquidated damages. Without one, the contractor bears the full financial consequences of late completion, which on large projects can run to thousands of pounds per day.

Extension of Time (EOT) Claims

An EOT claim is a formal request to extend the contractual completion date because of a qualifying delay event. Under JCT contracts, these are called "Relevant Events" and include:

• Variations and changes to the works
• Late or inadequate design information
• Exceptionally adverse weather conditions
• Civil commotion, strikes, or lockouts
• Force majeure events
• Statutory undertakers' delays
• Opening up for inspection where the work is found to be compliant

The notification requirement

Almost every construction contract requires the contractor to notify delay events promptly. Under NEC4, the requirement is explicit: the contractor must notify a compensation event within eight weeks, or the entitlement may be lost entirely. JCT contracts are slightly more forgiving but still require notice "forthwith" or as soon as reasonably practical.

The golden rule of delay claims: if you do not notify it at the time, you will struggle to claim it later. Contemporaneous notification is everything.

As a site manager, you are usually the first person to know that a delay is occurring. Your responsibility is to flag it immediately, both to your own contracts team and formally to the client's representative. Do not wait until the monthly progress meeting. Do not assume someone else will raise it.

Loss and Expense Claims

An EOT extends the completion date but does not, on its own, compensate the contractor financially. For that, a separate claim for loss and expense is usually required. This covers the additional costs incurred as a direct result of the delay, such as:

• Prolongation costs - site overheads for the additional time on site (site staff, welfare, plant hire, scaffolding)
• Disruption costs - loss of productivity caused by working in altered conditions, out of sequence, or with restricted access
• Acceleration costs - if the contractor incurs additional expense to recover time, such as overtime, additional labour, or weekend working
• Head office overheads - the contribution to head office costs that the project should be generating, typically calculated using the Hudson, Emden, or Eichleay formulae

Loss and expense claims require detailed financial evidence. The site manager's role is to provide the factual foundation: what happened, when, why, and what resources were affected. The commercial team then quantifies the financial impact.

Concurrent Delay

Concurrent delay occurs when two or more delay events happen at the same time, and at least one is the contractor's risk and at least one is the employer's risk. This is one of the most contentious areas in construction law.

The general approach in UK law, following the Malmaison principle, is that if there is a true concurrent delay, the contractor is entitled to an extension of time but not necessarily to financial compensation. However, the precise outcome depends on the contract terms and the specific facts.

From a practical standpoint, the best thing you can do is maintain records that clearly separate the different causes of delay. If you can demonstrate that the employer's delay would have caused a certain period of delay regardless of the contractor's own delays, your claim is much stronger.

The Site Manager's Role in Delay Claims

You may not be the person who drafts the formal delay claim, but you are the person who creates the evidence that underpins it. The quality of your site records directly determines whether a claim succeeds or fails.

What to record

1. Daily site diary - weather conditions, labour numbers by trade, plant on site, key activities, visitors, instructions received, delays encountered
2. Photographs - date-stamped, showing conditions, progress, and any obstructions or access issues
3. Correspondence - every instruction, query, or notification, with dates and recipients
4. Programme updates - regular updates to the construction programme showing actual progress against planned progress
5. Labour allocation records - where resources were deployed and any reallocation due to delay events

Common mistakes that undermine claims

• Not keeping a daily diary - a blank diary for the critical period destroys credibility
• Vague entries - "rain stopped play" is not sufficient. Record the exact conditions, what trades were affected, and what could or could not continue
• Late notification - even if the contract does not strictly bar late claims, late notification suggests the delay was not significant enough to mention at the time
• Mixing facts and opinions - record what happened factually. Leave the interpretation to the claims team

Practical Steps to Protect Your Position

1. Notify immediately - the moment you identify a delay event, send formal written notice to the contract administrator
2. Keep the programme current - update it regularly so you can clearly show when and where delays occurred
3. Maintain a daily diary without fail - this is your single most important document in any delay dispute
4. Photograph everything - conditions, progress, obstructions, completed work. Digital timestamps are your friend
5. Separate the causes - when multiple delays overlap, record each one independently so they can be analysed separately
6. Do not sit on it - if you are aware of a potential claim, raise it with your commercial team immediately. The earlier they engage, the better the outcome

Delay claims are rarely won on legal argument alone. They are won on the quality of contemporaneous evidence. As the person on the ground, you hold the keys to that evidence every single day.