Insight: “While we’re at it…” The most expensive sentence in construction

Few phrases have derailed more construction budgets than: 

“While we’re at it…” 

It usually comes from a perfectly reasonable place. 

The walls are already open, so perhaps now is the time to upgrade the electrics. The scaffolding is already erected, so maybe the roof should be replaced as well. The kitchen design is looking fantastic, so perhaps it makes sense to extend into the pantry while the builders are on site. 

Individually, none of these decisions seem particularly significant. 

Collectively, they have the potential to transform a well-planned project into one that overruns on both cost and programme. 

In prime residential construction, where every project is bespoke and expectations are exceptionally high, scope creep is one of the biggest reasons projects exceed their original budget. 

Small decisions rarely stay small 

Clients often assume that adding work during construction should be relatively inexpensive. 

After all, the contractor is already on site, but the reality is rather different. 

A seemingly simple change can trigger a chain reaction across the entire project: an additional room may require structural redesign, revised building control approval, extra steelwork, alterations to mechanical and electrical systems, updated joinery packages and changes to finishes that have already been ordered. 

What began as a straightforward idea quickly affects multiple consultants, subcontractors and suppliers. The cost is rarely limited to the additional work itself. It also includes the disruption that change creates. 

Time is just as valuable as money 

Budget increases are often visible. Programme delays are not. 

Every design revision requires drawings to be updated, information to be reviewed and subcontractors to adjust their work. Materials may need to be reordered, specialist manufacturers may have long lead times, and carefully planned construction sequences can be disrupted. 

On high-end residential projects, where bespoke stone, handcrafted joinery and specialist finishes are common, even a modest design change can affect the programme by several weeks. 

For clients working towards a planned move-in date, family event or seasonal deadline, that delay can become more significant than the additional construction cost. 

Some changes make perfect sense 

This is not to say that changes should never happen. 

Construction projects evolve. Clients refine ideas as spaces begin to take shape, and occasionally unforeseen conditions uncover opportunities that genuinely improve the finished home. 

The key difference is whether those decisions are made with a full understanding of their impact. 

Good project management is not about saying “no”. It is about ensuring every change is informed by clear advice on cost, programme and risk before the decision is made. 

Sometimes the right answer is to proceed immediately. 

Sometimes the better answer is to incorporate the idea into a future phase of works, avoiding unnecessary disruption and protecting the overall project. 

The value of early planning 

Many of the most expensive changes originate from decisions that could have been explored much earlier. 

Investing additional time during the design stages allows clients to test different layouts, finishes and technical requirements before procurement begins. 

That process often feels slower at the outset, but it creates significantly greater certainty once construction starts. 

Every major decision made before work begins is one less decision that needs to be made when contractors, suppliers and consultants are already committed to a live programme. 

Building flexibility into the budget 

No project is entirely predictable; hidden defects, planning conditions and client decisions will always introduce a degree of uncertainty. 

Rather than pretending these risks do not exist, experienced project teams acknowledge them from the beginning. 

Appropriate contingencies, structured change management and regular cost reporting allow clients to make informed decisions without losing control of the overall project. 

The objective is not to eliminate change. It is to ensure that change remains a choice rather than a surprise. 

Conclusion 

“While we’re at it…” is not a phrase that should never be spoken. 

Sometimes it leads to genuinely valuable improvements that make a home more enjoyable, more practical and better suited to its owners for decades to come. 

The difference lies in understanding the true cost of those five words before acting on them. 

The most successful projects are not those where nothing changes. They are the ones where every change is considered carefully, its implications are understood and decisions are made with confidence rather than impulse. 

At Selway Joyce, our role is to provide that clarity. By combining project management with detailed cost advice, we help clients understand the wider impact of design changes, protecting budgets, programmes and ultimately the quality of the finished project. 

Speak to our team about early cost advice and project support.