What should you consider when building a house?

*Update: Please contact our team for current pricing.

Building a house is a life project that we will probably undertake only once in our lifetime. That is why it involves an investment of time and money that does not leave us indifferent, so it is most common for our clients to come to the studio with two main questions: how much it costs to build a house and how long it takes to build it.

In today’s article we will summarise what you should consider when building a house, to clarify questions of time and money as well as other details that are more likely to go unnoticed. We must not forget that the process begins long before the construction of the future home itself, so in the article we will also focus on a series of points prior to this key phase—specifically, 5:

1 Budget assessment with the bank

Financial feasibility

We could even say that the first 4 points to consider when building a house do not necessarily have to happen in this order. Each person has their own process and personal circumstances, so it may be that we start with a plot or area in mind, begin from a design idea, or have a very clearly defined brief. However, it is true that the key point to begin is to see what budget we have available both for the plot and for the home.

The project’s financial feasibility is divided into two concepts that we should clarify as soon as possible. The first is to know how much we have available to invest in the form of our own savings, and the second is to confirm the financing options we have, which is usually through a bank.

Financing

Most commonly, the bank will ask us to have sufficient savings to cover the purchase of the plot.

The option of mortgaging the purchase of the plot is usually only accepted if you have 20% of the total cost of the plot and the house—that is, taking out a mortgage for part of the plot and for the house. This option is very complicated, because it would require the plot seller to agree to sell it with a deposit and a contract with a completion date several months ahead, since the bank does not grant a mortgage on the plot until there is an approved project and a building permit. In addition, our architect is not going to finance the project, so we will need savings to pay for both the project and the building permit. It is not impossible, but it is a complex option to carry out.

In addition, in this case there are procedures whose execution does not depend on us, such as the building permit. The bank does not grant a mortgage until the project has been approved and the building permit has been granted. For the project, the architectural team can adjust timelines and work ahead to manage the date, but the delay in granting the permit is not in our hands, but in those of the municipal technicians at the town hall, and each municipality has its own timelines and regulations.

So we move directly to the second option, in which the bank finances only the construction of the home. Again, we must bear in mind that the bank does not grant a mortgage until there is an approved project and a building permit, so there are some costs such as the purchase of the plot and its associated taxes, the detailed design project to apply for the building permit, and the cost of the building permit.

At our studio, Slow Studio, we have a philosophy that prioritizes the health and sustainability of our projects, as well as personalized client care. That is why, just as we advise clients to contact a project team that shares a similar life philosophy, in the banking sector we always try to work with ethical banking. This type of banking—such as Triodos Bank in Spain—prioritizes investment in projects that provide social value, or self-promoted homes built with efficiency and sustainability criteria.

Amortization

In a similar way to when we explain the advantages of building an eco-friendly house rather than a conventional one, we may not choose ethical banking for budget reasons, but for principles and benefits beyond the purely economic. However, it is worth noting that an eco-friendly house allows us to save in the long term, minimising the so-called energy mortgage.

At present, the average mortgage for an eco-friendly house is around €230,000–€250,000, not including the plot. The bank will release funds as the construction progresses and we submit certificates confirming the completion of each stage.

2 Purchase of the plot

Finding and purchasing a plot is a highly variable process, so it can take from days to years. On the blog we have covered in various articles how to choose a good plot, because studying the plot’s characteristics is essential to approach the design correctly and reduce costs.

Technical Aspects

An eco-friendly home is based on the principles of bioarchitecture, whose strategies make the most of the site’s natural resources to minimise energy consumption. After finding the desired plot online, an in-person visit is essential to assess the plot in terms of orientation, slope, services, and the immediate surroundings.

Administrative Aspects

Administrative aspects involve checking the status of any charges, debts, or easements on the plot to ensure we do not buy it with any outstanding debt. By reviewing the building regulations, we can also adjust the house design in parallel and reduce costs.

Legal Aspects

Before starting the process of purchasing a plot, we should take the precaution of requesting a land registry extract (nota simple) from the relevant Land Registry and confirming that the plot has no debts or charges.

Once we are sure everything is correct, we must formalise and sign a deposit contract (contrato de arras). It is also worth noting that the purchase tax is much lower if you buy from a private individual (TTP) rather than a company (VAT).

3 Finding the project team

Depending on whether we have been searching for the plot independently, already have it, or have sought advice from an architecture studio, we will be at one point or another in this search phase. However, nowadays there is an increasingly wide range of architects, as well as easier access to this information thanks to the digital era, which makes all information available on the internet and social media.

As with everything, such an endless range of possibilities has its drawbacks, and a number of very low fixed-price construction offers appear. Behind these are construction companies that promise prefabricated homes with a fixed design and very low quality. These companies have an architect because Spanish law requires it, even if that professional is subordinate to the company’s economic interests.

If what we want is to prioritise personalised, high-quality service, we must find a project team with whom we can communicate well and share a philosophy, until we reach an agreement on fees and formalise a contract. In our case, Slow Studio is a young, energetic studio that combines a close, adaptable approach with the principles of bioclimatic architecture.

4 Design

The point that seems most obvious to us to consider when building a house is the design of the project itself. The design phase is divided into two parts: the preliminary design and the construction project, or detailed project, which includes the basic and detailed design stages:

Preliminary Project

The preliminary design is the phase that requires the most involvement from the client; it is also the most creative and complex in terms of defining our future home. Once it is approved with the project team, it will be the architects’ job to develop the technical side to make its construction a reality.

Everything starts with the client, who must define their own brief that answers the question: what will my house be like? In our case, the Slow Studio team holds a first meeting at the client’s current home to understand their private world and create an initial connection with the family by understanding their needs and requirements.

A combination of all the variables we have detailed so far that must be considered when building a house comes together to formalise a solution: the client’s activity programme, together with the characteristics of the chosen plot and the budget available. All of this with passive design and net-zero consumption criteria.

We always say that architecture is not an exact science, so solutions are not unique, but they may fit the client’s expectations better or worse. That is why, following the initial meeting, we make a proposal that will then be refined in a series of meetings with the client.

Construction project

The construction project, in turn, is divided into two sub-phases: the basic design and the detailed design.

The basic design defines the construction system and details, while the detailed design includes structural and services calculations, detailed finishes, and all project measurements, which will allow us to produce an accurate budget.

In a similar way to finding the project team, but simpler, the contractor tender essentially consists of choosing the construction company that will make our future home a reality. It is usually the architecture studio that handles the process, sending the construction project and measurements to various contractors—in our case, we usually send it to three.

Each contractor responds with an offer, which is usually based on the measurements provided, but also includes technical details on how the construction process will be carried out in terms of timelines. The different offers are compared and the one that convinces us most is chosen, always trying to negotiate to ultimately award it to the best bidder. At this point, a contract is signed.

In our case, this is a process we carry out with complete transparency. However, the architect–contractor relationship has not always been synonymous with clarity. As a client, one factor to consider when building a house is the relationship between these two parties. The fact that the architect is a different team from the contractor ensures that the architect is on our side at all times, defending our interests.

6 Construction

We come to the last, but no less important, section: construction, which we can divide into a series of phases: site preparation, foundations, structure, internal and external enclosures, services, finishes, and final documentation. As we have mentioned throughout the article, it is a more or less lengthy process depending on the level of prefabrication of the materials.

Throughout this process, the architecture studio usually takes charge of site supervision together with the quantity surveyor (arquitecto técnico), a figure that is legally required in Spain. This monitoring is carried out through a series of weekly site visits, during which cost control is supervised in parallel, coordinating the stage-completion certificates with the bank.

But the process does not end when the works themselves are completed; there are still a series of documents needed to legalise our home: the occupancy certificate, registration at the Land Registry, and utility connections. At the same time, at Slow Studio we show the client how to use passive architecture elements to our advantage, to save energy and improve both comfort and health.

Are you considering building a house?

If you have the wonderful project of building a house in mind, you now have several tips on what to consider when building a house. As we have outlined throughout the article, Slow Studio works as an integrated studio that supports you throughout the entire process, from start to finish. We look forward to hearing from you!