Greenery and observation decks top hillside villa by António Costa Lima
A concrete walkway projects from the street onto the roof of this concrete home in Caxias, Portugal, which is designed to go unnoticed from a hilltop road (+ slideshow).
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_7.jpg)
Designed by Portuguese studio António Costa Lima Arquitectos, the wedge-shaped House in Caxias tapers in height towards the top of its sloping plot. Residents can walk from the street onto its L-shaped roof, which doubles as a viewing platform.
The spaces within the building are oriented away from the road to face towards the West Jamor Valley in Caxias, a district just under ten miles along the coast from Lisbon.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_8.jpg)
Decked and planted roof terraces are accessible from each floor and help to create a connection with the gardens that surround the three-storey family home.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_0.jpg)
"The slope of a long and narrow plot inspired the genesis of the concept of property, a volumetric assimilation of the house as part of outer space," said the architects. "The house is the garden itself on its outer surface."
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_10.jpg)
A narrow flight of concrete steps descend from one side of the roof, past a bank of planting and onto a patch of decking where glazed doors slide into a hallway and the first of five bedrooms.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_4.jpg)
An open-plan living area and kitchen are spread across the floor below, while a garage and utility space occupy the ground level.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_3.jpg)
While the house is designed to be almost imperceivable from street level, it appears as two stacked concrete blocks from the base of the site.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_13.jpg)
"Given the slope, the house presents two ends in contrast," explained the architects. "The west side an almost non-existent facade with a gradual entry into the house and the east side as a fully opened object facing the lovely valley."
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_11.jpg)
"In fact, the house is hardly perceived from the road, revealing itself as an exception to the street morphology: a plot without a house," the architects added.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_5.jpg)
A slatted wooden canopy – matching the timber fences that surround the gardens – extends between the board-marked concrete walls of the two blocks. It provides a sun shade for a decked terrace in front of the first-floor living room.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_6.jpg)
A glazed wall concertinas from the face of the living space to provide access to the terrace, which is fronted by a concrete parapet.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_14.jpg)
Inside, a pale timber staircase with a slim white banister connects a series of split-level spaces, which are staggered to accommodate the inclination of the site. Floors are covered in wood that matches the staircase, while the walls and recessed shelving are painted white.
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_468_15.jpg)
Photography is by Fernando Guerra.
Project credits:
Architect in charge: António Costa Lima
Team: Francisco Lobo, Pedro Araújo, António Fraga, António Silva
Engineering: Francisco Domingos
Construction: Gardenblock
Structures: 686 Construções
![House in Caxias by António Costa Lima Arquitectos](https://static.dezeen.com/uploads/2015/03/House-in-Caxias-by-Antonio-Costa-Lima-Arquitectos_dezeen_1.jpg)
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