How much an apartment renovation costs: what makes up the budget

What makes up the renovation budget?

The interior itself is made up of five items:

1. Construction work — demolition, building partitions, laying screed and plaster, installation.
2. Rough-in materials — mixes, plasterboard and profile, waterproofing, fixings: everything that goes under the finish and is never seen.
3. Building services — electrics, water supply and drainage, heating and underfloor heating, ventilation, air conditioning, low-voltage systems.
4. Finish work — tiling, flooring, paint, doors, hardware.
5. Furnishing — furniture, lighting, plumbing fixtures, textiles, decor.

On top of these five items come the costs of running the job itself: delivery, hoisting and storing items, procurement management, design supervision and a reserve for changes. These usually don't show up in the interior estimate, but the same budget pays for them.

In the construction section, it's easier to count labour and materials separately, which is how they're listed above. Building services break down into equipment and materials plus installation, and in finish work the cost of the material itself and the cost of laying it are shown separately. Furnishing has no such split: there you pay for the object.

The cost of design work isn't included in this budget: the design project is costed separately. As the level of materials, furniture and equipment rises, the share of design work in the overall interior cost usually falls. Details are in the article “How much does an interior design project cost”.

Why floor area alone isn't enough to work out the budget

The most common expectation at the start is that the budget can be derived from the floor area. In practice, floor area sets the quantities: metres of screed and plaster, metres of tiling, the length of runs and boxing. The price of those metres is set by the level of the decisions, and that is what makes two identical apartments differ several-fold in cost.

The same 30 m² living room can be painted and furnished with off-the-shelf furniture, or finished in stone and veneer with furniture made to drawings. In the second case, the labour becomes noticeably more expensive — complex installation is priced differently — but predictably so. The furnishing becomes many times more expensive.

So the question “how much does a square metre of renovation cost” hangs in the air until another one is answered: what level of furnishing you are aiming for. It's more honest to start the conversation there.

Furnishing — the item that gets underestimated

On high-end projects, furnishing can become the largest item in the budget, sometimes comparable to the whole construction section or larger. The reason is simple: this item has no upper limit. Screed costs whatever screed costs. A sofa can cost as much as the screed for the whole apartment, or as much as the entire renovation.

One common mistake is to leave furnishing for later and set aside for it only whatever is left of the budget: mentally, a person is preparing for a “renovation” but ends up with a finished interior. By the time it comes to purchasing, it turns out most of the money has already gone into what can't be seen.

The correct order is the reverse: the level of furnishing is fixed at the concept stage, together with the materials. Then the specification is put together against a budget set in advance, rather than the budget being stretched to fit the specification. How the stages follow one another is covered in the article “The sequence of renovation work under a design project”.

Building services get noticed once they can no longer be redone

In a preliminary budget estimate, building services are easy to underestimate: in the finished interior, most of them are hidden. But it's exactly these systems that determine what the interior will be like to live in: whether the supply ventilation runs quietly, whether the bedroom air conditioner creates a draught, whether there's enough power for the kitchen appliances, where the distribution board is tucked away.

Key building services decisions have to be factored in as early as the layout stage: the geometry of ceilings and boxing depends on them. Changing them later often means demolishing structures that are already built. In the budget, this is an item where savings go unnoticed on move-in day and show up every day after: if the work has to be redone, the cost of the systems themselves is joined by the cost of restoring all the finishes that have to be opened up. How this works in practice is covered in the article “Ventilation in a designer renovation”.

Responsibility for building services is split according to who did what. In the interior project, the studio sets the requirements, positions and setting-out of the building services elements and coordinates them with the layout, ceilings, furniture and lighting. Full calculations and the specialist design packages (ventilation, air conditioning, heating, low-voltage systems) are handled by specialist engineers. Responsibility for installation lies with whoever carried it out: if a third-party contractor is running the construction, the studio records deviations in the design supervision log, but it's the builder who corrects them and answers for them under warranty; when the studio itself runs the construction, responsibility for the work is the studio's.

What pushes the budget up

A budget almost never collapses because of one big decision. It falls apart through a dozen small substitutions along the way, each of them made on the grounds that “we're redoing it anyway”. Each one looks insignificant, right up until the moment they're all added into a single line.

• Reconfiguration. Demolition, building work, approvals and the related changes to building services form a separate cost block that simply doesn't exist if the layout stays as it is.
• Custom-made pieces. Built-in furniture, surrounds, non-standard ceiling details: each item is made to its own drawing and to on-site measurements, which means a separate lead time and a separate price.
• Complex geometry. Concealed doors, shadow gaps, frameless glazing, multi-level ceilings: this is work of a different precision, and so a different installation cost.
• Delivery lead times. Items with a long production cycle either dictate the schedule or get swapped out in a hurry, and a rushed substitution costs more: if not in money, then in the result.
• The unforeseen. A reserve is worth setting aside as its own line, not just kept in mind: the exposed floor turns out to be three centimetres lower than expected, a wall isn't quite vertical, an item gets discontinued between approval and ordering. Its size depends on the condition of the site and the degree of uncertainty; a benchmark of 10% of the construction section is often taken as a starting point.
• Storage. The furniture arrives on contract, the construction falls a month behind, and storage turns into a budget line nobody planned for.
• Rework. The most expensive work is the kind you have to do twice, and it isn't in the original budget. Most of this kind of rework is prevented by full technical documentation: what's already been decided on paper isn't decided all over again on site.

When the estimate becomes precise

It's worth separating two words that often get confused. The budget is a planning horizon: how much the whole interior will cost, together with furnishing, project management and reserve. The estimate is a construction document with specific quantities and rates, rigid by its nature. The budget exists from the very first conversation, the estimate appears after the project.

Before technical documentation and specifications exist, you can only reliably talk about a range. The project makes it possible to put together a detailed estimate: to fix the quantities, the specific materials and equipment, and to request prices from contractors and suppliers. The price becomes contractual once the parties have fixed it, or the method of determining it, in the contract; an agreed estimate can become part of that contract. It is also worth knowing whether that estimate is fixed or approximate: the two behave very differently when the price has to move.

An example: what an estimate for materials and equipment looks like

Below is a real document from one of the studio's projects in a boutique residential building. This isn't construction work or rough-in materials, but everything purchased against specifications: finish work, doors, furniture, lighting, plumbing fixtures, textiles and climate-control equipment. Ninety-five line items, each with its own price and supplier.

The document is dated 26 July 2023, and it's worth looking at as a structure rather than a price list: the European manufacturers' prices were converted into roubles at the euro exchange rate on 25 July 2023 and have risen since then, as have locally sourced items. The value here isn't in the totals, but in how many lines the purchase is made up of and how the weight is distributed between them.

The estimate's total comes to about €0.5 million, and that's the purchase of materials and equipment, not construction work. Inside it are things that usually don't surface at all in a preliminary guess: parquet, doors, in-floor radiators, curtains and bed linen, ventilation with air conditioning. Taken separately, each line looks straightforward; the total builds up through their sheer number. And it can only be put together once the decisions are fixed in the project; before that, any figure remains a range.

Hence the sequence that saves the most: first the budget frame, then the project within it, and only after that a detailed estimate against fixed decisions. The reverse order — when a crew names a price before the project exists — means some decisions will be made on site, and their cost will surface as you go along. More detail is in the article “Design project or renovation without one”.

What helps keep the budget under control

Full technical documentation. The saving here isn't in materials: good documentation reduces the number of decisions that have to be made right there on site, and the risk of rework that comes with them.

Fixed specifications. When items are approved before purchasing, any substitution along the way is made deliberately, weighing the price against the consequences for the schedule.

Furnishing and procurement. A base rate of from €500/month plus a commission of 10% of the cost of the items purchased. The value here lies in managing the purchasing schedule: items are ordered with production lead times and construction stages in mind, which reduces the risk of downtime waiting for a door ordered a month later than it should have been.

Design supervision. from €700/month. A deviation caught before the next layers of finish cover it over is usually fixed locally. The same deviation found after the finish work is complete requires demolishing something already finished.

Construction to the studio's own project. from €450/m² per metre for the labour; materials and equipment are costed separately, against the project's specifications. The contractor who worked with us on that project puts construction labour on projects of this level at 50–80 thousand roubles per metre (2023 estimate). The scope of work and included materials vary between contractors, so these figures aren't compared directly. When design and construction sit within a single management system, any deviation from the drawing is resolved within one team, and the client doesn't have to reconcile the designer's and the contractor's items themselves.

How to work out your own budget

A preliminary estimate for the design work can be obtained through a short questionnaire — it calculates the design project, not the renovation budget. The renovation budget itself is put together once the project is ready: from the specifications and quantities in the technical documentation.

Before the project exists, you can work out the range your project falls into: leave an enquiry or start with a consultation — in an hour, the studio works through the layout, the site's constraints and your budget priorities, and it becomes clear where the line between “enough” and “too much” falls in your case.