Recognising the best residential architecture of 2019, RIBA's House of the Year award is upon us once more. With the winner finally revealed on Channel 4's Grand Designs, this year's longlist vying for the crown features everything from a secret subterranean city home to a property built entirely from cork. Let's take a look at the bright new homes of 2019 and find out which one proved better than the rest...

This intriguing home, designed by Adam Richards Architects, occupies the site of a former farmhouse. The fascinating property is something of an optical illusion – the home's three storeys play with proportions, with the upper floors appearing as squat half-levels at first glance, while an array of shaded bricks around the arched windows contort the shape of the structure in unexpected ways. It's no surprise then that this unusual dwelling has recently snapped up a place on RIBA's coveted shortlist.

From the street, this innocuous-looking brick villa, designed by Cousins & Cousins, holds its secrets close to its chest – it's only when you venture around to the rear of the property that the genius behind the design becomes apparent. Resembling the swish modernist pad of a Bond hero or villain, swathes of glass cascade down the structure, drawing the eye toward the basement, which hides a sauna, swimming pool and even a Thunderbirds-style car lift. 

A first of its kind, this unique property, designed by Matthew Barnett Howland with Dido Milne and Oliver Wilton, has been crafted entirely from cork. As a result, it has an exceptionally low carbon footprint and impressively, all of its parts can be reused or recycled. Inside, the minimalist interior, which includes exposed cork and oak flooring, is bathed in light thanks to numerous skylights in the hive-style roof.

Designed to maximise breathtaking views over the Irish Sea, this beautiful home on the Isle of Man slots seamlessly into the rural landscape. With a long slim horizontal window and thick walls, the property is built like a fortress, offering a snug shelter from the elements. Recently claiming a place on RIBA's shortlist, architects Foster Lomas turned to nature to power the home too, with a lake-sourced heat pump fitted to keep the interior warm and cosy.

Love this? Check out the mind-blowing architecture that shouldn't work but does

Built on an underutilised site that once housed garages, this striking new family home succeeds at both protecting the privacy of neighbouring properties and creating an array of bright and airy living spaces. Extending below ground, the innovative dwelling's tactile structure of brick, timber and concrete has been left exposed throughout the interior for a modern industrial feel. Designed by Tikari Works, the property has just made RIBA's shortlist so watch this space...

Nestled in a small plot between two Georgian terraces in Kensington, planning constraints limited this property to just one storey. As a result, Sophie Hicks Architects decided to dig down, creating a basement level housing two bedrooms and bathrooms. From the street, only the white garden wall and a slither of glass can be glimpsed, offering no hint at what lies underground...

Inspired by the work of Japanese architect Tadao Ando, BPN Architects brought to life this remarkable house, constructed within the sunken garden of a now-demolished country house. The vast main living area features a glazed wall spanning its entire length, offering airy open-plan living. This space opens out onto a large restful courtyard punctuated by small reflection pools and cherry trees, in stark contrast to the brutalist concrete structure.

Intuitively designed, this timber building with a sweeping green roof appears entirely at home in its rural environment. Perched on the hillside, the angular structure blends in with the surrounding threes thanks to its rustic wood cladding. Inside the space is dramatic, with floor-to-ceiling glazing and window seats offering the perfect vantage point to admire the fields and ponds below.

Designed by Niall McLaughlin Architects, this striking modernist dwelling comprises an array of staggered rectangular units built from timber. Made from stone, oak and flint, the structural materials reflect the home's idyllic riverside setting and draw inspiration from its shores. One of the property's wow-factor features, a sculptural floating staircase connects the levels, while a simple neutral interior lets the rolling views do all the talking.

Flint, stone and oak come together to form this modern energy-efficient build in East Sussex. Designed by Meloy Architects, the sleek structure comprises a single storey, with a wing of four bedrooms set at a right angle to a central open-plan living space. The property is protected by a screen of mature trees, while stunning views of the valley below can be glimpsed from the kitchen.

Located in the back garden of a 19th-century townhouse in London, this architectural marvel, conceived by Gianni Botsford Architects, is a house of hidden depths. A sculptural copper roof and floor-to-ceiling windows channel light into the enclosed property, while a clever series of lightwells illuminate the home's two underground levels, once of which houses a tranquil swimming pool.

Love this? Discover these spectacular homes hidden from the world

James Gorst Architects built this stunning modern manor house in a tranquil rural spot in Northamptonshire. Reminaging the traditional farmhouse, the enclosed stone property hides a number of courtyards and gardens within the complex of stunning lime-washed buildings. Inside, rustic joinery, fireplaces and chimney stacks evoke a snug Scandi aesthetic for a modern twist on tradition.

Built within a pre-existing barn complex in the rural idylls of Northern Ireland, this sleek new home sits in perfect harmony with the surrounding verdant landscape. The work of McGonigle McGrath, the new forecourt, bedroom block and living spaces seamlessly slot into the agricultural property – an achievement made even more impressive by the project's modest budget.

Earning itself the moniker of Britain’s first-ever Passive House Plus, this groundbreaking ‘healthy home’ produces twice as much energy in a year as it consumes. The exquisitely designed glass and brick property relies on the sun, wind and rain for its power, drawing 97% less energy from the grid than the average UK home. Designed by bere:architects, the innovative dwelling spells exciting things for the future of sustainable homebuilding.

Inserted into a modest mews in London, this unassuming home by bere:architects is both respectful of its position in an established residential street and pioneering in its clever cost-saving design. Insulated shutters dramatically reduce heat loss, while heat pumps offer a sustainable heating system. Adaptable for the future, the ground floor of the property is future-proofed to make it completely accessible for wheelchair users. Talk about smart design!

A merging of modernity and tradition, this unique family home in Llanhennock saw new life breathed into a historic Arts and Crafts stable block when it was sensitively renovated and linked with a glass corridor to a newly-built red sandstone wing by Hall + Bednarczyk Architects. Inside, the home's contemporary Scandi-inspired interior sits beautifully alongside revived period details, from slate work to tiles and charming dormer windows.

Love this? You won't believe these amazing home conversions

Designed by Atelier Peter Zumthor with Mole Architects, this striking hilltop home in Devon was built using rammed concrete, a painstaking layered construction process that results in a dramatic striped facade. Large spans of glazing frame 360-degree views of the valley below, while the rippled concrete walls inside add a modern industrial feel to the space.

A masterclass in transforming awkward urban sites into innovative homes, this unique structure by Jonathan Pile Architect sits a stone's throw away from a Grade I-listed church. The property responds sensitively to its historic location, with the black-stained timber facade referencing the structures of 17th- and 18th-century homes in the area. Nestled underground, the lower storey's characterful beams frame welcoming living spaces, dominated by spectacular vistas of the church.

Designed by James Boon Architects, this unimposing new build property feels at home in its picturesque village location. Natural stone walls and stained timber cladding pay homage to the local architecture, offering an exciting blueprint for new homebuilding in sensitive rural locations. Inside, a double-height living area with a vaulted wooden ceiling creates a cosy space to kick back and relax, while a wood-burning fire forms the traditional heart of the home.

Perched on a rocky shoreline, this angular black structure by Dualchas Architects has real wow-factor. Clad in rustic timber cladding, the facade merges with the rugged natural landscape to stunning effect. The interior is similarly pared-back, with minimalist lines, warm wood tones and swathes of glass framing spectacular waterfront views. So which house has taken the crown?

House Lessans, a compound of converted farm buildings in County Down designed by McGonigle McGrath, has been named RIBA House of the Year 2019 on Grand Designs. Through a clever use of basic building materials, cost-saving hacks and a purposefully simple arrangement of rooms the house cost just £1,425 per square metre (£335,000) – a remarkable achievement for a newly built home of this scale.

With its austere look, the house has not been a huge hit with viewers who took to social media to complain that it 'looks like a prison'. But Chair of the 2019 RIBA House of the Year jury, architect John Pardey, argued that the house "has an elegant simplicity achieved within a remarkably low budget" and “represents relevant contemporary architecture that truly reflects its local context".

Built on the site of a former farmstead, Lessans House is formed of two perpendicular blocks made from white rendered concrete blocks – carefully laid, rendered outside and painted inside with flush mortar joins to ensure a perfect finish – and capped with zinc pitched roofs overlooking a tranquil sheltered courtyard garden. The huge windows are also fixed throughout with openings for ventilation which is a far cheaper alternative to bifold doors. 

The breath-taking open-plan kitchen and snug take advantage of the views with huge expanses of glass, while the three, equally-sized bedrooms are restrained, private and more familiar in scale. "It is a joy to live in – from seeing the soaring bedroom ceiling on wakening, being surrounded by the gentle landscape in the kitchen during the day, to enjoying the sunset in the top room," said the owners, Sylvia and Michael.

Loved this? Step inside the world's most amazing off-grid homes