UK Construction Material Prices Rise, Increasing Project Cost Risk

The latest UK construction data gives project teams a clear warning for the second half of 2026. Construction material prices have started to rise again, even while some indicators of demand remain weak. The Department for Business and Trade’s June 2026 construction materials commentary shows that the “All work” material price index rose by 5.4% in May 2026 compared with May 2025. Some product categories experienced sharper increases. These included fabricated structural steel, gravel, sand, clays, kaolin and bituminous mixtures.

For developers, consultants and contractors, cost planning must respond to a mixed market. Inflationary pressure can remain high even when activity is subdued.

A mixed picture across the construction market

The latest figures show weaker deliveries across several key products. Brick deliveries fell by 4.4% and concrete block deliveries fell by 9.1% in May 2026 compared with May 2025. Ready-mixed concrete sales also fell by 12.0% in the first quarter of 2026 compared with the first quarter of 2025. Sand and gravel sales were down by 6.6% year on year. These indicators often reflect the health of new building activity. They are particularly relevant to housing and early-stage construction. The Office for National Statistics construction output release for April 2026 shows a similar pattern. Total output increased by 1.6% in the three months to April. However, new work rose by only 0.3%. Repair and maintenance increased by 3.4%. This points to a market where maintenance and refurbishment remain comparatively resilient. New work continues to face pressure from viability, procurement and programme risk.

Why construction material prices matter

Rising construction material prices can affect many more things than just the headline project budget. They can influence:

• Specification decisions
• Tender returns
• Contingency allowances
• Procurement strategy
• Programme planning
• Contract selection

Project teams should pay close attention to packages that depend heavily on steel, aggregates and asphalt-based products. Even when overall demand is softer, individual products can still become more expensive. This may be caused by energy costs, logistics, manufacturing capacity, imports or sector-specific demand. Generic inflation assumptions may therefore be unreliable. Cost plans should reflect the materials, systems and procurement routes proposed for each project.

The value of early cost advice

Current market conditions strengthen the case for early and regular cost advice throughout RIBA Stages 1 to 4. Early advice gives clients a clearer understanding of affordability and gives the design team a realistic commercial framework.

RIBA Stage 1: Testing the business case

At Stage 1, cost advice can test the brief, business case and early assumptions against current market conditions. This helps clients understand whether the available budget is realistic before the design team develops detailed options. Early advice can also identify major risks linked to site conditions, project scale, specification and programme.

RIBA Stage 2: Comparing design options

At Stage 2, cost advice can compare design options, site strategies and outline specifications. This makes it easier to identify where cost risk is developing.nCommon areas of risk include:

• Structure
• Building envelope
• Mechanical and electrical services
• Sustainability measures
• External works
• Site infrastructure

Addressing these issues early can help the team protect the design intent without losing control of the budget.

RIBA Stage 3: Supporting planning certainty

Cost advice becomes especially important at Stage 3 because the design is often being prepared for planning. A realistic cost plan can reduce the risk of submitting a proposal that later becomes unaffordable. Without clear cost information, clients may need to make significant changes after planning approval. This can create additional work and delay progress.

RIBA Stage 4: Preparing for procurement

At Stage 4, detailed cost planning supports technical design, tender preparation and procurement. It can help teams enter the market with clearer information and more appropriate contingency allowances, and it can reduce uncertainty during contractor discussions and limit avoidable surprises during tendering.

Protecting planning information and programme

Late cost pressure can create a difficult chain reaction. When a project becomes unaffordable after planning approval, the team may need to reconsider:

• Materials
• Layouts
• Building massing
• Façade treatments
• Servicing strategies
• Sustainability features

Depending on the scale of the changes, approved planning information may also need to be updated.

This can lead to planning amendments, further submissions and additional consultant work.

It can also delay procurement and unsettle contractor discussions. Funders, occupiers and other stakeholders may face greater uncertainty.

Good cost advice cannot remove market volatility. However, it can help clients respond earlier and make better-informed decisions.

It allows the client to set a more realistic budget before key approvals are fixed. It also helps the design team work within clearer commercial boundaries.

Not all materials are moving in the same direction

The latest figures should not be treated as a prediction that every material will rise at the same rate.

Some products moved in the opposite direction. Cement prices fell by 5.0% year on year, while concrete reinforcing bars fell by 1.2%.

The more useful conclusion is that the market remains uneven.

Broad indices can hide major differences between product categories. Project teams should therefore avoid relying solely on generic inflation allowances.

Where material choices have a significant effect on cost, the cost plan should consider those products separately.

What clients should monitor next

The next few months will show whether the recent rise in construction material prices becomes a sustained trend or a short-term pressure point.

Project teams should monitor:

• Tender price movement
• Supplier lead times
• Manufacturing capacity
• Contractor appetite
• Import costs
• Changes in construction output
• Recovery in new work

For now, materials risk should be treated as an active project issue rather than a background assumption.

Cost advice from RIBA Stages 1 to 4 can support better budgeting and more informed design decisions. It can also reduce the risk of changes to approved planning information.

Most importantly, it can help projects stay on programme as they move from early design to tender and delivery.