The statement: “Restoring the Palace of Westminster may cost £40 billion and take 61 years” may seem exaggerated, as noted in the report issued by the UK Parliament on February 5, 2026, and reported by Bloomberg, but it actually provides an excellent window into understanding the economics of restoring historic buildings: why does it take so long? Why does the bill jump? And how can the decision of “execution method” be more important than the decision of “whether to restore or not”?

The rule that explains most of the story is simple:
The more constraints on execution, the slower the work, and the higher the cost.
In historic buildings, constraints are not just details… they are the essence of the project.

The Language of Numbers

  • £40 billion: The highest cost estimate for some scenarios.
  • Up to 61 years: The highest duration estimate for the “phased evacuation” option.
  • £1.5 million per week: What is spent on ongoing maintenance and repairs.
  • £15.6 billion: The highest cost estimate for the “full evacuation” option.
  • £39.2 billion: The highest cost estimate for the “phased evacuation” option.

Why Can Restoration Take Decades?

1) Because the “evacuation method” changes everything

In the case of Westminster, two common options appear in any large historic building:

  • Full evacuation: Moving the occupying entity (Parliament/Museum/University/Court) to an alternative site, then executing the restoration all at once.
  • Phased evacuation: Dividing the project into stages while part of the use continues or moving between internal locations.

Economically, phased evacuation is like trying to change an airplane's engine while it is flying: you will get the work done, but at a slower pace, with higher risks and more complex coordination.

2) Because real restoration often happens “within the walls”

People see the scaffolding and the facade, but most of the restoration time goes to what is not visible: electrical systems, ventilation, fire systems, service tunnels, moisture treatment, and rehabilitation of structural parts.
In a historic building, you may open a small section only to discover an old network, hazardous material, or a structural defect that was not visible. This necessitates stopping then redesigning then approvals before resuming. This chain alone is enough to extend the timeline.

Here, an important economic term appears in context: Execution risks.
Its meaning is simply: “What might appear during the work that changes the plan?” The higher the risks, the longer the expected time and the higher the price that the contractor and consultant demand because they bear the uncertainty.

3) Because “working during operation” creates wasted time

When you keep part of the site operational, you will face additional constraints: temporary walkways, safety and security requirements, limited working hours, and repeated closures and openings.
This may seem politically or service-wise logical, but economically it reduces productivity (how many meters/how many systems can be completed in a day). With reduced productivity, the duration of execution increases.

Why Do Costs Jump?

1) Because time itself raises the bill: inflation and costs of keeping the project

Long projects are affected by a fundamental economic factor called inflation: the rise in prices over time.
Even if the scope of work does not increase, extending the project over decades means that wages for labor, materials, and engineering services at the end of the project will be higher than they were at the beginning.

Moreover, there is what can be termed “the cost of operating the project”: engineering differences, management, security, insurance, testing… that operate for an additional year if the timeline extends by an additional year.
This is not a luxury; it is a necessary cost to keep the project safe.

2) Because “heritage” imposes more expensive solutions

In modern construction, many systems are standardized and installed quickly.
In heritage, many solutions are customized, requiring specialized craftsmen and materials that meet the requirements of preserving architectural identity. The scarcity here raises the price.

3) Because the cost of “continuous patching” is not a cheap alternative

Spending £1.5 million per week on maintenance reflects an economic concept called patching cost: you pay to avoid the worst today, but you do not address the root cause.
Over time, patching may turn into a drain—because you are continuously paying, and then you also pay a large restoration bill later.

4) Because governance affects costs just as concrete and steel do

In the report, criticisms were directed at governance and accountability.
“Governance” here is not just an administrative term; its economic meaning is clear: who decides? How is the budget monitored? How is unnecessary project scope creep prevented?

And when governance weakens, a well-known risk in large projects appears called scope creep: the project gradually expands with additions and modifications, extending the timeline and increasing the bill, not because the initial idea was wrong, but because the decision was not made early or because oversight weakened.

How Do We Read Restoration Projects in Any Country?

When you hear about a restoration project “taking years and costing billions,” do not start by asking: Why are they exaggerating?
Start with these four questions—they usually explain 80% of the story:

  1. Will the site be completely closed or will it operate during restoration?
    Full closure is often faster and clearer, while working during operation is often slower and more expensive.
  2. Where are the biggest costs: the facade or the internal infrastructure?
    If the focus is on internal systems (electrical/fire/ventilation/service tunnels), expect more surprises and longer time.
  3. What is the degree of uncertainty?
    The older and less documented the building, the higher the execution risks, and the higher the price and reserve, and the greater the chances of changing the plan.
  4. Who governs the project? Who is accountable?
    Large budgets need strong governance because a small delay in a big decision can equal millions, and scope creep can happen quietly… then appear as a “sudden jump” in cost.

Restoring historic buildings is not just about “aesthetics,” but an economic decision between two options:
Either a faster radical repair with temporary relocation arrangements, or a longer phased restoration that satisfies daily operations but inflates the project time and bill. In the end, time is not just a number on a schedule… it is part of the cost.