Few construction projects finish on time and within their original budget, so much so that delays and overruns are treated as inevitable. But the causes of construction delays and cost overruns are no mystery; they recur in most projects, from the small villa to the large factory, and most can be controlled if identified early. The difference between a project that finishes close to plan and one that runs a year late is usually decisions made before construction starts. This guide sets out the most common causes and tools to prevent them, change management, early warning signs, and the role of the contract and consultant.
The Most Common Causes and Their Solutions
| Cause | Preventive tool |
|---|---|
| Design changes during construction | Freezing the design before tender, and using 3D design to decide early |
| Clashes between discipline drawings | A coordination review before construction. Read: Clashes between drawings |
| Unclear quantities and specifications | Detailed bills of quantities and specifications before pricing |
| Choosing the contractor on price alone | Technical and financial comparison. Read: Comparing contractor bids |
| Late owner decisions | A decision schedule with set dates |
| Supply delays | Ordering long-lead materials early |
| Delays in regulatory procedures | Preparing permit files early. Read: Building permit duration |
| Workmanship errors requiring rework | Regular supervision and inspection points before pouring. Read: Pouring supervision stages |
Before Construction: Where the Battle Is Won
- A complete design coordinated across disciplines.
- A soil report that prevents foundation surprises. Read: The soil investigation report.
- Bills of quantities and specifications that reduce change orders.
- A clear contract with a schedule and payments linked to progress.
- A realistic contingency budget.
Change Management
Every change must have its effect on time and cost assessed before approval, and be documented with a change order. Any change affecting the licensed building's components needs a regulatory route. Read: Modifying approved drawings and Risks of changes without drawings.
Early Warning Signs
- Actual progress below plan for two consecutive weeks.
- Recurring quality observations on the same item.
- Payment requests running ahead of progress.
- Frequent changes in the contractor's site team.
- The contractor late in submitting samples and materials for approval.
Read: Progress reports and releasing payments.
The Consultant's Role
The consultant does not prevent every problem, but finds problems early when they are cheaper to fix, and documents them in a way that protects the owner in a dispute. Read: How the consultant prevents disputes and delays and Project management and supervision.
Frequently Asked Questions
Who bears the cost of delay?
The contract terms decide; that is why drafting the contract is part of prevention.
Does a project manager eliminate risk?
No, but they detect it early and manage its effect.
What contingency is appropriate in the budget?
It depends on project size and design maturity; the more complete the design, the less contingency is needed.
What should I do if the contractor is very late?
Document the delay with the supervisor's reports and refer to the contract terms. Read: Engineering reports in disputes.
Are material prices a main cause of overruns?
They can be, so fixing prices or setting an adjustment mechanism in the contract helps.
How Abak Engineering Consultancy Helps
Abak is an accredited engineering office in Riyadh that manages and supervises projects with preventive tools: coordinated design, bills of quantities, bid comparison, progress reports and documented change management. See our engineering project management service, or contact us.
Regulatory information is based on the Balady platform and the Ministry of Municipalities and Housing, and procedures may be updated by the competent authority. Last reviewed: October 2026.