Illustrative two-storey ICF villa under construction with tall openings, recessed balconies, white EPS surfaces and one worker in a yellow DUO Building vest, overlooking a Portuguese coastal landscape.
Greater Lisbon and Margem Sul

We build homes
ready for
the future.

High-end construction, built with ICF technology, providing strength, comfort and energy efficiency.

Our Services

Illustrative portrait of a friendly woman in a charcoal blouse, with part of the DUO Building sign behind her.

Tell us about your project.

Whether you need the ICF structure or a complete home, we’ll help you plan the next steps. With more than 5 years of experience and a specialist technical team, including engineers, we can review your architectural plans and adapt them for ICF construction.

What is ICF?

ICF is a modern system for building reinforced-concrete structures on site. It allows a wide range of architectural designs, with the structure built to suit your project.

Insulating EPS forms are assembled on your plot, steel reinforcement is placed inside, and concrete is poured into the cavity. The EPS stays in place as permanent insulation beneath the interior and exterior finishes.

ICF can be used for homes, apartment buildings and swimming pools. Different concrete core thicknesses are available to suit the structural requirements of each project.

How ICF works?

The formwork comes together.

Two interlocking EPS panels are joined by plastic webs. The webs hold the panels apart and provide guides for the horizontal reinforcement.

Steel reinforces the wall.

Horizontal steel bars are placed into the guides on the plastic webs. Vertical bars are then inserted in two parallel rows and tied to the horizontal bars with wire.

Concrete forms the core.

Concrete is poured on site around the steel reinforcement, forming the wall’s load-bearing core. The EPS stays on both sides as permanent insulation.

White EPS formwork with red guide webs and paired steel reinforcement inside the wall.

EPS panels are joined by six plastic webs, each with six guide teeth above and below. Horizontal steel bars rest between the upper guides, clear of the EPS. Paired vertical bars are tied to the horizontal steel with wire. A see-through panel reveals the reinforcement. Dark concrete fills the cavity around the steel; EPS remains as insulation. This is an explanatory section, not a structural specification.

See how an ICF home is built

Follow the construction stages, from the foundations and first forms to the structure, finishes and handover.

Illustrative wide view of an ICF home under construction with two workers assembling formwork.

The build, explained on film.

This video is not available. You can explore the construction stages on our Why ICF page.

Explore the construction stages

A closer look.
A better place to live.

Select an icon to explore the details.

Illustrative side section of the hero house completed: bedroom and living room, insulated reinforced-concrete walls, foundations and repeated black dome formwork creating ventilated voids beneath the ground-floor slab.

Thermal comfort

ICF’s continuous insulation and concrete core can reduce energy use by 25–50% compared with conventional timber- or steel-frame homes.

Quieter rooms

ICF walls can let through less than a third as much sound as standard timber-frame walls, keeping rooms quieter.

Structural strength

The continuous reinforced-concrete core gives the house strength to resist wind and earthquake forces.

Floor slabs & spans

Reinforced-concrete floors span up to 10 metres without intermediate columns, giving you larger, open rooms.

Moisture control

The ventilated space beneath the ground floor carries moisture and radon outside, reducing damp and soil gas entering the home.

Our Projects

Illustrative contemporary Portuguese home with pale stone, sheltered glazing and an olive tree.

Riverside home

Almada, Setúbal

Area
220 m²
Rooms
4 bedrooms
Levels
2 storeys
AI-generated illustration of a single-storey home around a planted courtyard.

Courtyard home

Azeitão, Setúbal

Area
185 m²
Rooms
3 bedrooms
Levels
1 storey
AI-generated illustration of a two-storey home on a planted hillside.

Hillside home

Sintra, Lisbon

Area
210 m²
Rooms
4 bedrooms
Levels
2 storeys
White architectural line drawing of the current homepage hero villa, with two storeys, recessed balconies, tall openings, flat roof and foundation separated in an exploded view.

FAQ

Can I get in touch before I have a plot or plans?

Yes. You can start with an idea. Tell us what you would like to build and where you are looking. We can discuss the next steps and what information will be useful as the project develops. You do not need to send drawings with your first enquiry.

Can you build just the structure, or the complete home?

Both. Choose an ICF structure if you will arrange the remaining work, or complete home construction with an agreed handover stage. The proposal sets out exactly what is included.

Where do you work?

Our current focus is Greater Lisbon and Margem Sul. If you are considering another location in Portugal, tell us where. We will discuss whether we can support your project.

What happens after I get in touch?

We contact you to understand your project and priorities. We then discuss the details needed for an individual estimate. Plans can be shared later in the conversation; there is no automatic price calculation.

Can you work with my architectural project?

Yes. We can discuss how your design could be built with ICF. After the initial conversation, we review the relevant drawings and identify any adaptations needed before developing the proposal.

Have a bold idea?
Let's discuss

Discuss your project