Talking about how much it costs to renovate a flat without seeing the property is, at best, a rough estimate. Even so, there are useful price ranges that can help you make informed decisions. In Barcelona and other cities with an established housing stock, the final budget does not depend solely on the square footage. It is determined by the actual condition of the property, the extent of the work required and, above all, the scope of the project.

A renovation can be limited to updating finishes or become a comprehensive transformation that rethinks the layout, fixtures, lighting and storage. The financial difference between one option and the other is significant. So too is the spatial outcome.

How much does it cost to renovate a flat depending on the type of work

If the question is how much it costs to renovate a flat, it is best to start with the scope of the work. It does not cost the same to renovate a kitchen and paint as it does to completely overhaul a property with a new layout.

For a partial renovation, the usual cost ranges from €350 to €700 per square metre. This typically includes painting, flooring, minor interior carpentry, updating the bathroom or kitchen, and aesthetic improvements without making major changes to the structure of the space.

A mid-range full refurbishment usually costs between €800 and €1,200 per square metre. In this scenario, we’re talking about replacing electrical and plumbing systems, renovating bathrooms and kitchens, changing floors, doors, wall and floor coverings, and lighting, and, in many cases, adjusting the layout to create more space and improve functionality.

When the project aims for a more sophisticated result, featuring bespoke design, specialist joinery, high-end materials, well-integrated climate control and a superior level of detail, the budget usually starts at €1,200 per square metre and can easily exceed €1,800. In penthouses, older properties or homes with complex technical constraints, the figure may rise further.

Indicative prices by property size

Providing examples helps to manage expectations. A 60 m² flat undergoing a full refurbishment can, as a rough guide, cost between €48,000 and €72,000 in the mid-range. If bespoke solutions, a higher-end kitchen or complex layout changes are included, the cost can rise to €85,000 or more.

For an 80 m² property, a well-executed full refurbishment typically starts at around €64,000 and can reach €100,000 depending on the quality of finishes and complexity. For flats of 100 m², the usual range for a complete refurbishment is approximately between €80,000 and €120,000, with significant variations if there is custom-made furniture, acoustic improvements or structural work.

These figures are indicative and do not always include all items using the same criteria. This is where one of the main sources of confusion lies: comparing quotes that appear similar but do not cover the same things.

What makes a flat renovation more expensive

The first factor is the condition of the property. An older flat may conceal outdated installations, uneven floors, damp, or partition walls that do not match the original plans. When demolition begins, unforeseen issues come to light.

The second factor is the layout. Opening up the kitchen to the living room, adding a bathroom, relocating the plumbing area or completely rethinking the layout of the home has a direct impact on the building work, installations and finishes. It’s not just about knocking down walls. It’s about redesigning how the home functions.

The type of building also plays a role. Renovating in a block with complex access, a small lift, restrictive timetables or a demanding residents’ association tends to increase timeframes and logistical costs. And in older buildings, any work requires greater technical precision.

The fourth factor is material quality. Between standard porcelain tiles and large-format tiles, between a modular kitchen and a bespoke kitchen, or between basic joinery and an integrated solution, the price difference is clear. But so too is the difference in appearance, durability and spatial coherence.

What items make up the actual budget

To understand how much it costs to renovate a flat, you need to look beyond the overall figure. A proper budget is broken down into sections.

Demolition and waste management usually account for a moderate portion of the cost, but they are necessary to get off to a sound start. Next come masonry, plastering, false ceilings and surface levelling, which often absorb more of the budget than anticipated when the flat is in a very poor state of repair.

Installations are a key item. Electricity, plumbing, drainage, air conditioning and, where applicable, telecommunications or home automation can completely transform the level of comfort in the home. Cutting back here to keep the budget in check often proves costly later on.

Next come wall and floor coverings, interior and exterior joinery, kitchen furniture, bathroom fittings, lighting and painting. In more elaborate projects, bespoke storage solutions, integrated appliances, metalwork details or acoustic treatment are added.

Finally, there are technical fees, licences and charges. These are not a minor extra. They are part of the project and should be taken into account from the outset.

The role of the design in the final cost

Trying to save money by skipping the design phase almost always backfires. Without a clear plan, the build becomes riddled with last-minute decisions, changes, delays and cost overruns.

A good project organises the budget before work begins. It defines the layout, materials, lighting, fixed furnishings, construction solutions and coordination between trades. This allows the investment to be aligned with the client’s actual objective, not the changing pace of the build.

In practices such as FFWD Arquitectos, the value lies not only in designing an attractive space. It lies in translating an aesthetic and functional vision into a coherent execution, where every decision adds value and the budget responds to an overall logic.

Basic, comprehensive or premium renovation: which makes sense

Not all homes need a comprehensive refurbishment. In flats intended for rental, a selective update can improve perception and profitability without requiring a complete overhaul. But a distinction must be made between a cosmetic improvement and a long-term investment.

If the property is for your own use and you are seeking comfort in the medium to long term, it usually makes more sense to address fixtures, layout and storage from the outset. Carrying out a superficial renovation and reopening the works two years later usually costs more.

In properties with architectural merit, good views or prime locations, a more ambitious design approach usually pays off, not only financially but also in terms of quality of life. The key lies in aligning investment, property type and realistic expectations.

How to calculate a budget without falling into unrealistic figures

The most reliable estimate does not come from an isolated price per square metre, but from an honest conversation about priorities. Will the kitchen be moved? Will the windows be replaced? Is there bespoke furniture? What standard of finish is expected? Is energy efficiency a priority? Each answer narrows down the range.

As a practical guide, it is advisable to set aside an additional 10 to 15 per cent for contingencies, particularly in older properties. Not because the work is poorly planned, but because renovation involves working with an existing structure that is not always fully revealed until the work begins.

It is also advisable to be wary of quotes that are too low. A very aggressive figure often hides omissions, poor quality or a lack of detail. The problem does not appear on the first page of the quote, but during the work.

How long a renovation takes and why this also affects the price

Time and cost are linked. A partial renovation can be completed in a few weeks, but a full renovation of 80 or 100 m² usually takes between three and five months, depending on complexity, supplies and administrative procedures.

When planning is poor, deadlines are extended and costs rise. Delays arise between trades, changes in materials, pending decisions and corrections that could have been avoided. A well-designed renovation not only improves the end result; it also keeps the schedule on track.

The right question is not just how much it costs to renovate a flat

The fundamental issue is not just how much it costs to renovate a flat, but what kind of home you want to create within that existing shell. Some renovations simply replace materials. Others refine proportions, organise the light, improve circulation and make the space truly work.

When the budget is approached from this perspective, the cost ceases to be an isolated figure and becomes a project tool. That is where a renovation begins to make sense: when every euro invested improves the use, the atmosphere and the daily life of those who will inhabit the space.

Before asking for fixed figures, it is worth defining what you want to keep, what you want to change and what level of transformation you expect. That initial clarity does not magically reduce costs, but it does prevent costly mistakes and opens the door to a better-planned, better-executed and far more liveable renovation.