Looking at the four-level corner terrace that now stands on Lorong Pisang Hijau in Upper Bukit Timah, you would never imagine that this used to be the site of a one-storey home. Designed by Czarl Architects, a 586sqm residence occupies the 375sqm triangular plot where the owner and his family have been living since the late-1970s. 

When the eldest son in the family’s third generation got married and had a child, the Tans commissioned the firm to create a new home on the same plot that would comfortably accommodate four generations.

In order to meet their brief, Carl Lim, Czarl Architects’ Founder and Principal, developed a design that provided adequate privacy for each generation. At the same time, he ensured to promote a strong sense of connection and togetherness between the family units. 

Named V House, it sits at a road junction next to a park full of lush trees, which Lim was careful to take advantage. This was carefully balanced with reducing the intensity of heat penetration through the eastern façade.

“We asked ourselves how we could maximise the land despite its odd triangular shape and create new identity elements for a four-generation household,” says Lim.

A challenging plot

The most crucial aspect of the site was the triangular shape, which has a sharp tapering corner. This called for a V-shaped floor plan rather than the typical rectangular floor plan. 

“The project’s central idea was to approach the site with the intention of embracing its unique qualities and turning perceived challenges into opportunities. With this commitment, we opted to push the building envelope to its maximum and embrace the resultant triangular, prismatic volume as the logical conclusion of deliberate optimisation of the building setbacks,” explains Lim.

In doing so, the uncompromising volume of the house presented an unusual opportunity to create an interesting and unique façade design. 

“Rather than enclosing the building with a typical facade of glass, which did not serve to address the tropical heat, we envisioned the odd-shaped volume as a folded, robust, concrete thermos-skin that acts as a blank canvas for assembling and puncturing openings, holes, apertures, cut-outs of voids and vents in all sorts and manners,” he says. 

“This playfulness of volume and vents stands in stark contrast with the black cantilevered, monolithic slab over the car porch, which runs along most of the home’s northeast frontage.”

With the V-shaped floor plan, most of the habitable spaces are located along the periphery of the building, while spaces for circulation and utility are located to the centre of the house, next to the shared party wall with its neighbour.

Playing peek-a-boo

To achieve the delicate balance of maintaining privacy, while drawing in views of the old trees in the park and sidewalk along its facades, Lim employed strategies for mapping the exact required scale and position of the vents onto different facings of the house. 

For the northeast frontage facing the park, one particular mature rain tree was singled out as the subject of visual interest. This helped guide him in determining the ideal size and location of the openings in the rooms on the second and third levels, so they would frame the lush crown of the rain tree. 

To reduce heat gain from the morning sun through the eastern façade, a single cavernous vent was carved onto that side, thus creating a huge, open-sided courtyard that enables ample natural light and ventilation to reach deep into the interior of the house. Trees were introduced into this courtyard to create visual continuity with the sidewalk greenery outside the boundary wall.

The main facade design incorporates ventilation blocks, which provide passive cooling and thermal comfort. “They allow for natural airflow, so cool breezes can enter the house and expel hot air. The blocks were also strategically positioned to enhance thermal comfort within the house. They facilitate the exchange of fresh air, helping to regulate indoor temperatures. 

“This feature is particularly beneficial in Singapore’s tropical climate, where maintaining a comfortable indoor environment is essential. By promoting natural ventilation, the house minimises its reliance on mechanical cooling, enhancing the occupants’ well-being while reducing energy demand,” says Lim.

In contrast to both the front and northeast façades, maximising views and ventilation was prioritised over privacy on the attic floor due to its high vantage point. “Here, the robust concrete skin peels gradually away at its edges to form a corner frame of the distant landscape. As the attic loft is a spatial continuation of the floor below, from here, one gets a surreal view of the ever-changing skies from the son’s dwelling on the third floor,” says Lim.

Balancing public and private

The family’s dynamics and lifestyle, privacy and autonomy, and social interactions, along with functional adaptability, were key factors that influenced Lim’s design decisions. 

The architects conducted in-depth discussions with the family members to gain insights into their individual preferences, daily routines, and aspirations. This helped them to develop spaces that would accommodate diverse activities and promote harmonious coexistence. 

“For example, the second generation likes to entertain and have guests over, while the third generation tends to be more reclusive and appreciates privacy, so one of the main challenges was balancing privacy for each generation, while maintaining a sense of connection,” says Lim. 

Responding to this need, he created separate floors with dedicated living spaces, bedrooms and bathrooms for each family unit. The first and second floors mainly cater to the first and second generations, while the third and attic floors act as self-contained duplex apartments for the newlyweds. 

This arrangement offered the necessary privacy and autonomy, so each generation has their own personal space within the family home. To create a seamless spatial flow that encourages interactivity between family members, open floor plans, interior spaces that are visually connected and strategically positioned common areas were included in the design. 

“Features like large main windows and terraces were employed to provide glimpses of shared spaces and facilitate natural light and visual connectivity. The house is also connected by a main connecting volume, consisting of a staircase, as well as a lift to aid in the movement throughout the floors for all generations,” says Lim. 

Recognising that family dynamics and life stages evolve over time, convertible rooms and multipurpose spaces that can be adapted to changing future needs were also included. 

Outdoor social areas, such as balconies, roof terraces and a central courtyard, were also integrated to provide space for the family to connect with nature and spend quality time together. 

The layout ensures that family members enjoy ample daylight within their respective living areas. This consideration contributes to the overall well-being and visual connectivity within the house, while reducing the usage of artificial lighting.

“The design of this house encourages seamless interaction and communal activities, while at the same time, offers private spaces for personal retreat and individual autonomy,” concludes Lim.