10 Ways to Avoid Costly Variations During a London Refurbishment
Variations are one of the most common reasons a refurbishment finishes above its original budget.
Some changes are unavoidable. Existing buildings can hide defective pipework, structural issues, damp, damaged substrates or outdated services that simply could not be fully assessed before work began.
Others, however, arise because decisions were made too late, the original scope was unclear, or work started before enough of the design had been resolved.
In construction terms, a variation is broadly a change to the agreed scope of works. RICS notes that variations can result from changes to employer requirements, statutory changes, material availability or design revisions, and they will commonly affect the contract sum.
The aim should therefore not be to pretend that every variation can be eliminated. It should be to reduce avoidable changes and manage unavoidable ones properly.
Here are ten practical ways to do that:
1. Develop the Scope Before Asking Contractors to Price
The more information missing at quotation stage, the more assumptions contractors have to make.
If a quotation simply says “refurbish bathroom” or “form new kitchen”, there can be significant differences between what the client expects and what the contractor has allowed for.
Before pricing, define the major elements of the work as clearly as reasonably possible.
For example, instead of asking for a new bathroom generally, establish whether the scope includes new sanitaryware, plumbing alterations, waterproofing, tiling, lighting, ventilation, decorating, joinery and disposal of the existing fittings.
The clearer the starting scope, the fewer opportunities there are for disagreement later.
2. Complete Important Design Decisions Before Work Starts
Starting quickly can feel productive, but beginning construction while major design decisions remain unresolved often creates variations.
Kitchen layouts, bathroom positions, lighting plans, flooring transitions and joinery details can all influence other trades.
Moving a kitchen appliance after first-fix plumbing and electrics have already been completed may mean opening finished walls, relocating services and repeating work that has already been paid for.
Try to resolve decisions that affect several trades before those trades begin.
A few days spent coordinating the design beforehand can prevent considerably more disruption on site.
3. Understand Exactly What the Quotation Includes
Do not rely solely on the final price.
Read the assumptions, exclusions and provisional allowances.
A lower quotation may simply contain less work.
Check particularly for items such as:
- Site protection and temporary works
- Waste removal
- Electrical alterations
- Plumbing modifications
- Floor preparation
- Making good
- Decorating
- Final cleaning
- Scaffolding where required
- Specialist inspections or testing
Citizens Advice recommends obtaining detailed written quotations and being clear about the work required, precisely because written information helps establish what was originally agreed.
4. Investigate the Existing Building Before Committing to a Fixed Budget
Refurbishment is different from building on a completely clear site.
The existing property creates uncertainty.
Where practical, investigate suspicious areas before the main works start. This might involve checking damp, opening a small inspection area, reviewing existing electrical installations, testing plumbing or understanding the existing floor build-up.
For significant alterations, structural information should also be sufficiently developed.
Spending money on investigation can sometimes feel unnecessary, but it can convert an unknown risk into something that can actually be priced.
5. Keep a Realistic Contingency
A contingency is not spare money waiting to be spent on upgrades.
It is protection against genuine uncertainty.
For an existing building, it is sensible to keep part of the overall project budget outside the contractor's original price for unforeseen conditions and necessary changes.
The appropriate amount depends on the property's age, the level of investigation completed and the complexity of the refurbishment.
A heavily altered period property generally carries more unknowns than straightforward decorating and flooring works.
RICS guidance recognises that even well-planned projects with appropriate contingencies may encounter unforeseen or additional works.
6. Avoid Making Design Decisions While Trades Are Waiting
Site decisions often become expensive because they need to be made immediately.
If a carpenter is standing on site waiting to know the position of a doorway, or the electrician needs a lighting layout before closing a ceiling, delay can affect both cost and programme.
Maintain a decisions list before and during construction.
Typical items requiring early approval include:
- Tile selections
- Sanitaryware
- Ironmongery
- Light fittings
- Socket positions
- Joinery finishes
- Kitchen appliances
- Flooring
- Paint colours
The earlier these decisions are resolved, the easier it is for procurement and construction to remain coordinated.
7. Price Changes Before Instructing Them
A common source of frustration occurs when additional work is requested casually on site and the financial effect is only discussed later.
Wherever reasonably possible, request the cost before authorising a change.
A proper variation should identify what is changing and how that affects the price.
It may also affect the completion date.
RICS change-control guidance emphasises the importance of formally managing and documenting changes rather than allowing them to drift informally through a project.
This does not need to become bureaucratic on a small domestic project. Even a clearly documented email or variation schedule can make a significant difference.
8. Consider the Knock-On Effect of Every Change
A client may see a change as one item.
Construction rarely works that way.
Moving a doorway might affect electrics, skirting, flooring, decorating and bespoke joinery.
Changing from a standard radiator to underfloor heating could affect floor build-up, plumbing, controls and programme.
Before approving a variation, ask what else the decision changes.
The initial cost is not always the total cost.
Good project management looks at the complete consequence of a change rather than treating every trade in isolation.
9. Separate Necessary Variations From Upgrades
Not every increase in project cost is an unforeseen construction problem.
Sometimes the project evolves because the client chooses a higher specification or adds work.
That is perfectly reasonable, but it should be distinguished from genuine unforeseen works.
For example, discovering defective plumbing behind a wall is different from deciding halfway through the project to add bespoke cabinetry.
Keeping these categories separate makes it much easier to understand where the budget is going and whether the original scope itself was realistically priced.
10. Maintain a Live Variation and Cost Tracker
Do not wait until the end of the project to calculate the combined effect of all changes.
Maintain a simple running schedule.
For each variation, record the description, cost, approval status and any programme impact.
A refurbishment may contain several relatively small additions that individually appear manageable but collectively become substantial.
Regular cost reviews allow decisions to be made while there is still time to adjust specification or defer non-essential work.
That is one of the main differences between actively managing a refurbishment budget and simply reviewing invoices after the money has already been spent.
Good Change Control Protects the Project
Variations are not automatically evidence that a refurbishment has been badly managed.
Existing buildings contain uncertainty, and clients are entitled to refine their requirements.
The problem arises when changes are poorly defined, poorly priced or discovered too late.
A clear scope, coordinated design, realistic contingency and simple approval process can dramatically improve cost certainty.
The objective is straightforward: when the project changes, everyone should understand what changed, why it changed, what it costs and whether it affects completion.
Planning a Refurbishment in London?
Bayocorp provides refurbishment, renovation, fit-out, estimating, cost planning, project management and pre-construction support across London and the South East.
We help clients establish the scope properly, understand likely project costs and manage construction changes before they become expensive surprises.
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