Double Skin Envelope House Creates Microclimate

Designed by: ASOLIDPLAN.

Location: Singapore | Latitude: 1.31312˚ N

The double skin envelope on this house creates a functional and beautiful response. This outer wall system or envelope provides a unique climatic application for this tropical house.

Envelope House is a creative approach for designing in the dense urban environment of Singapore. ASOLIDPLAN are the architects of this great house.

House Design Brief

The client for this house is a young family with a child. However, the client’s parents and aunt also live there. Hence, the occupants of the home are multigenerational.

Each part of the family would need their own private space. In addition, shared spaces and generous green areas were part of the brief.

The house’s completion date was in 2020. It is 620m2 or 6,674 sq. ft.

House Design Layout

There are three storeys in this home.

The first level on the ground carries communal spaces. These include the living room, dining room and kitchens. They are also some outdoor spaces, such as a garden and courtyard.

Envelope House first, second and roof plan

The second level is where the client’s parents and aunt occupy. Their bedrooms, outdoor balconies and a lounge area are on that floor.

The young family occupies the third level. It has its stair and entrance to the outside. In addition to the bedrooms, there is also a family room, study, and balconies.

Photo: KHOO Guo Jie

A roof garden sits at the top of the house.

Double Skin Envelope

“We formulated the parti as a landscape double skin enveloping three levels of habitable spaces and punctured by a vertical landscaped courtyard.”
– ASOLIDPLAN

The double skin envelope of this house is one of its main features.

What is a Double Skin Envelope?

The envelope of a building is essentially the components that separate inside from outside. These usually include the outer walls, windows, doors and roof.

Therefore, a double-skin envelope describes a home or building with two outer layers separating the interior and exterior. They could be different materials or even different constructions. For example, one layer could be masonry, like bricks or concrete blocks, while the other could be a lightweight frame and panel construction.

However, they can be the same material as with this house.

Benefits of Double Skin Envelopes In The Tropics

Double skin envelopes in tropical climates can reduce the heat gain on the interior of your home. They provide solar shading to the inner walls and, by extension, the interior rooms. Hence, providing better thermal comfort and reducing the need for mechanical cooling like air conditioning. Therefore, it is a more sustainable design.

Photo: KHOO Guo Jie

Double skin envelopes can also assist in creating an interesting aesthetic for your home. The outer layer can be freer from some restrictions, such as where window and door openings need to be.

In this house, the outer layer has seemingly random openings of various sizes.

Planters, balconies and a stair occur between the two layers of the double-skin façade.

Courtyard

In addition, the courtyard, which has vents and skylights at the top, promotes more ventilation throughout the home.

Everyone in this house has private spaces. However, the house’s courtyard design connects all three floors.

At the ground floor level of the courtyard is a pond with steppingstone pavers and garden planters. A cool little reading nook accessible by the stepping stones is next to the pond.

Photo: KHOO Guo Jie

Hanging above the pond is the metal and timber stair between the ground and the first floor. On the top floor, a sky bridge passes through the courtyard and connects the family room with the master bedroom.

Photo: KHOO Guo Jie

This crisscrossing of the stair and bridge through the courtyard provides opportunities for chance encounters of the family members.

“The triple-volume indoor water garden – with a staircase weaving through foliage and a sky bridge crossing the tree canopy – brings nature indoors and into the residents’ everyday life.”
– ASOLIDPLAN

Microclimate And Biophilia

ASOLIDPLAN uses the double skin envelope and the courtyard to create a microclimate within the home.

Essentially, a microclimate is when a small area has unique climatic conditions. It usually differs from the general climate outside of that specific area.

Biophilic design through natural elements such as plants, water and air movement can help create a microclimate within your home.

Envelope house incorporates planters between the two layers of the double skin. Plants and trees grow out of the planter boxes to create an attractive appearance from the street. However, they also protect from the west-facing sun where openings are in the outer skin.

“The landscaped double skin strategy and its effective biophilic and microclimatic effects show that there are still new ways to create tropical architecture in a dense urban environment like Singapore.”

Tall trees and a water feature through the courtyard significantly impact the indoor climate. They also introduce natural light and natural ventilation through the vents and skylights at the top of the courtyard.

Photo: KHOO Guo Jie

This courtyard creates a natural connection in the heart of the home.

“Going against developmental pressure, we convinced the client not to maximise the built floor area but to focus on the quality of the space instead. The result is an unconventionally generous and grand indoor garden spanning three levels and the intimate presence of greenery throughout the house.”
– ASOLIDPLAN

Therefore, they combine the landscaping in the double-skin envelope with the indoor water garden courtyard that spans all three levels. Along with the roof garden at the top, they all come together uniquely to create a connection to nature that is responsive to the tropical climate.

Hence, the interior microclimate of the home is comfortable. It is constantly cool and breezy despite its west-facing orientation.

Conclusion

Envelope House is a modern application of tropical architectural principles in a unique way. The double skin envelope, courtyard and use of biophilic strategies create a stunning home that fits within its tropical climate.

“We managed to create a climate-appropriate tropical house without the usual tropical architectural solutions of deep eaves and overhangs, which are increasingly difficult to achieve in land-scarce Singapore.”
– ASOLIDPLAN

My Key Takeaways!

I like the idea of a double-skin envelope for the tropics. However, the expense of that extra layer of wall concerns me.

ASOLIDPLAN does a great job of using the space between the two layers, in my opinion. Using the space as balconies, planters, and a stair makes it more functional than just a shading strategy. Hence, it becomes an essential part of the function and aesthetic of the home.

In addition, I think courtyards are excellent in tropical homes. They are a great way to bring in natural light and promote natural ventilation in a home. Vented skylights are a great way to allow light and ventilation while keeping the rain out and ensuring security.