Efficiency by system
Treat yourself to designing your own home.
Fixed price, a completion date with a penalty clause, specifications in writing — before you start deciding anything.
Fixed price, a completion date with a penalty clause, specifications in writing — before you start deciding anything.
All the upside of doing it your way.
None of the hassle of doing it alone. We coordinate everything. And you don’t pay a developer or an estate agent.
Before you choose a builder
Buy a finished home, or build one to measure?
Both are good ways to get your home. They are not the same.
Buying a finished home
You walk through it before you pay, and you move in sooner.
But someone else chose the plot, the orientation, the layout and the finishes, and the price carries the margin of everyone in between.
Building it on your plot
It takes longer, and the licence and the water and electricity connections depend on the town hall and the utility companies, not on us.
But it is the only way for the home to be yours from the very first line: your plot, your light, your rooms. No one else’s margin in between, with a fixed price and a completion date with a penalty clause in the contract.
Before you sign
We know what is holding you back.
Building your home should excite you, not make you dizzy. Here, one by one, are the real doubts — and what we do about each of them.
How do I find a builder I can trust?
Three generations building in this area since the nineteen-sixties
Can the budget spiral out of control?
Fixed price, in writing, before we start
Do I save by building, or by buying from a developer?
No developer. No estate agent
What happens if something comes up after the build?
A written guarantee in the contract, and the same hands, in the same town
How will I know everything has been done properly?
8 checks, with an independent laboratory where regulations require it
Will the build overrun?
A penalty for every week of delay, with a cap
None of these is down to luck. It is down to what you sign.
This is what the houses we build look like.
The Everhome wall
Inside, reinforced concrete like a column. The insulation is bonded to both faces, thicker on the outside, on purpose. The insulation thickness is adapted to each project. When we finish, we carry out a thermal imaging survey.
5 cm inner insulation
15 cm reinforced concrete
10 cm outer insulation
How we build your home
Fixed price, agreed in writing
Before we start, you know what you will pay, and it does not change along the way.
Completion date with a penalty clause
If we are late, it is deducted from the final payment. It is not a favour: it is a clause.
Our own building system
Reinforced concrete with insulation on both faces.
Eight checks
The ones required by regulations are signed off by an independent laboratory; the rest we measure in your house and hand over to you.
We speak your language
Antonio speaks with you in Spanish, with an interpreter if needed. Everything in writing — emails, WhatsApp, quote and contract — and calls through our team, in your language.
We come in before the architect
You do not need a finished technical design to know what your home will cost.
25 homes like yours
Around 25 detached homes in this area, as well as public works for town halls and provincial councils.
«Construcciones Antonio Serna was my father’s company. We closed it when he retired, in 2021. This is the same thing, under another name.»
We don’t ask you to trust us. We show you the data.
Eight checks before we hand you the keys, with an independent laboratory where regulations require it. Thermal imaging either shows it in the photo or it doesn’t — no number needed. Façade watertightness is measured before you get the keys, not discovered by you in your first winter.
Continuous insulation
«Fixed price» only means something if you know what is inside it
Foundations, structure, utility connections, kitchen and bathrooms, installations — and also what is NOT included, so you don’t come across it later.
The questions people really ask us
What if your building system fails?
Eight checks before we hand you the keys, with an independent laboratory where regulations require it, and three generations building in this area since the nineteen-sixties.
Can I extend the house later?
Yes, if the buildable area of your plot allows it — we check it with you before designing.
Do you build on rural plots without mains services?
Yes — Autonomy Pack: water, energy and fencing.
Tell us about your dream home. Let’s see whether we can help you build it.
We take on only a few projects at a time, on purpose: never more than three or four builds under way. Tell us about your plot and what you have in mind, and within 48 hours at most we will tell you whether we can help, with the same conditions as always: fixed price, completion date with a penalty clause.