Iran war construction costs are now the defining commercial risk for every contractor with live projects in H2 2026. On 5 May 2026, the Construction Products Association published the most significant downgrade to UK construction prospects since the pandemic. Overall activity is now forecast to fall 2.5% in 2026. Private housing output is forecast to fall 7%.
The second half of the year, the CPA warned, is likely to see sharp cost increases as Iran war construction costs compound through supply chains, energy markets and financing conditions. The CPA's head of construction research described it plainly: at the start of this year there was cautious optimism. That has been replaced by stark concerns over global factors and rising oil and industrial energy costs, leading to a spike in inflation. Even if the disruption were to end today, she added, a degree of damage has already been done.
Iran war construction costs are not a prediction. They are already in the procurement prices your teams are seeing, the delays on material orders and the CVR positions that no longer match the commitments your commercial teams have already made. Construction News reported the CPA forecast in full on 5 May, and the numbers are stark for every contractor with live projects in H2 2026.
The Numbers Behind the Iran War Construction Cost Surge
The Strait of Hormuz closure, which began 28 February 2026, disrupted roughly 20% of global oil supply in a single move. Oil above $100 a barrel drives up the cost of every energy-intensive manufacturing process, and construction materials sit at the centre of that chain.
Steel and aluminium
The producer price index for aluminium mill shapes jumped 39.1% year-on-year by February 2026. Steel mill products rose 20.9% over the same period. The Associated General Contractors of America published these figures on 18 March, alongside a warning from their chief economist Ken Simonson: the disruption of oil natural gas and aluminium supplies from the Middle East is pushing up Iran war construction costs further and causing owners to delay projects.
These are not future risk numbers. They are the rates your procurement team will see when they go to market on any steel-heavy or M&E package in the second half of 2026.
The materials most affected
Birketts' legal analysis of the Iran war and the UK construction industry, published 27 April 2026, identifies the specific materials now under pressure: aluminium hit a four-year high after Iranian strikes on smelters in Qatar and Bahrain, PVC is in short supply due to petrochemical disruption with prices up more than 30% in some markets, and Chinese manufacturing costs surged because China sources 90% of its oil from Iran. UK importers of lighting, electrical components and building materials manufactured in China are absorbing those increases now.
Sherwin-Williams has raised paint prices 9% and bulk solvent products 18%. Windows and doors manufacturers are issuing price increases effective June 2026. These are not speculative. They are confirmed supplier price letters already circulating in the market.
Energy and the UK indirect hit
UK wholesale natural gas prices rose roughly 75% between late February and 23 March 2026. Brick kilns, cement plants and glass factories, all energy-intensive UK manufacturers, absorbed immediate cost pressure. The Bank of England had been expected to cut rates in March. It did not, and CPI is now forecast between 3% and 3.5% through Q2 and Q3.
The CPA is clear that its forecast for a recovery in 2027 is built on an assumption of four months of disruption. If the conflict persists longer, the downside risks are severe and the 2027 recovery disappears.
How Iran War Construction Costs are Landing Across Markets
The impact is not uniform. Each market absorbs Iran war construction costs differently depending on supply chain proximity, contract structures and the proportion of activity that is publicly funded.
UK
Mid-sized UK contractors who bid work in late 2025 at 2025 prices are now delivering that work in a 2026 cost environment that has materially shifted. Seven in ten UK construction companies surveyed last week reported they expect severe impacts from the conflict over the next six months. Project starts have nosedived. Glenigan has warned that the war has exacerbated pressures on the construction sector by weakening economic growth. The pipeline of government-funded infrastructure, which the CPA still expects to grow 3.2% in 2026, is the only sector providing consistent cover.
US
Project abandonments surged 22.8% month-on-month in March 2026, the largest single-month rise since late 2025. Construction input costs rose at a 12.6% annualised rate in the first two months of 2026, before the war's full pricing impact had fed through. Without data centre projects, commercial construction planning is down 12.7% since March 2025. AGC chief executive Jeffrey Shoaf put a number on the threshold: there is a limit to how many Iran war construction cost increases the market can absorb before owners put projects on hold.
GCC
For contractors operating in the GCC, the exposure is structural. The conflict has disrupted the Gulf's economic model directly. Qatar, UAE, Saudi Arabia and Kuwait have all seen energy export disruption, supply chain reversal and construction cost inflation at rates that exceed what UK and US contractors face. Infrastructure pipelines in the region remain active, supported by state spending, but procurement timelines have extended and cost assumptions built before February 2026 are unreliable.
India
India's reliance on Middle Eastern crude translates directly into elevated energy and input costs feeding into construction activity. The rupee has weakened under inflationary pressure. Steel and cement pricing, both critical for India's infrastructure boom, are rising. The lagged effects of Iran war construction costs on Indian project cost-to-complete positions will become visible through Q3 and Q4 2026.
Where the Exposure Sits on Your Current Projects
Rising Iran war construction costs create different levels of risk depending on where a project sits in its lifecycle. The exposure concentrates in specific situations:
- Fixed-price contracts let before February 2026 with no cost escalation clauses, or with thresholds calibrated to a pre-war cost baseline
- Projects with major structural steel, aluminium, copper or M&E packages still to procure in Q3 or Q4 2026
- CVRs where the cost-to-complete section still references bill of quantities rates from the original tender
- Procurement strategies built around spot-market buying rather than forward orders or price-capped supplier agreements
- Import-dependent projects where delivery timelines have extended by one to two weeks as vessels reroute via the Cape of Good Hope
- UK contractors who factored Bank of England rate cuts into their financing assumptions for new project starts
Any one of these situations creates a gap between what the CVR shows and what the project will actually cost. The gap is not visible in the reported position until procurement commits at the new rate or the invoice arrives at closeout.
Three Steps Commercial Teams Should Take this Month
Retest every cost-to-complete assumption set before February 2026
A CVR built before the conflict is built on a cost environment that no longer exists. For every major package still to procure, compare the CVR cost-to-complete rate against current market rates. Where current rates exceed CVR rates, the gap is live margin risk that does not yet appear in the reported position.
This exercise is not theoretical. The CPA is forecasting sharp cost increases specifically in H2 2026. If your major packages procure in Q3 or Q4, the market you enter may be worse than it is today.
Audit escalation clause status across live contracts
Most contracts above a certain value carry cost escalation provisions. In a stable market they sit dormant. In the current Iran war construction costs environment they are active commercial tools. Identify which live contracts carry these provisions, what the trigger thresholds are and whether current material price movements have crossed them.
Birketts is already reporting that UK contractors are issuing early notices of delay citing force majeure and that new contracts are being drafted with clauses expressly addressing global events. Activating existing escalation provisions is not confrontational. It is the contractual mechanism the contract was designed to provide.
Close the gap between procurement commitments and your CVR
The defining commercial risk from Iran war construction costs is not the price increase. It is the lag between when the commitment is made and when it appears in the financial position. A purchase order raised today at a rate above the CVR assumption creates a margin gap that is invisible to leadership until the invoice lands.
When procurement and job costing run in a connected system, every purchase order creates a committed cost entry that immediately updates the cost-to-complete. The commercial team sees the margin impact of a procurement decision at the point of the decision rather than 60 days later. In a stable cost environment this is good practice. In H2 2026, it is margin protection.
What Connected Cost Management looks like in this Environment
Xpedeon connects procurement, job costing, CVR and financial accounting in a single platform. Every purchase order raised creates a committed cost entry that flows immediately into the cost-to-complete position. When material prices change between order and delivery, the system captures the variance at the point it occurs.
For Commercial Directors managing multiple live projects, Xpedeon's automated CVR reporting shows the current cost-to-complete across the portfolio, updated as procurement commitments are raised rather than waiting for a monthly cycle. In an environment where Iran war construction costs are moving faster than any monthly reporting cycle can track, that real-time visibility is what separates a managed exposure from a closeout discovery.
The escalation clause problem is also a data problem. Knowing which contracts carry clauses, what the thresholds are and whether current cost movements have crossed them requires that information to sit alongside the procurement and CVR data, not in a separate folder nobody opens until month-end.
The CPA's central forecast assumes four months of disruption. Even on that assumption, the effects lag through construction for 12 to 18 months. The Iran war construction costs that are moving now will be felt through 2026 and into 2027. The commercial teams that come through this well are the ones running live cost visibility rather than month-end reconciliation. That is the conversation our team has every week with Commercial Directors and CFOs managing live projects.
Book a discovery call with the Xpedeon team.