A house clad in pieces of flint, designed for one of the world's richest families, has been named the best new house in the UK by the Royal Institute of British Architects.

The winner of the Royal Institute of British Architects' (RIBA) House of the Year prize was announced as the climax of a TV series shown on Channel 4 last night.

Commissioned by Jacob Rothschild, head of the historic banking family and lord of the Waddesdon Manor estate where the house is located, Flint House is a wedge-shaped home for a visiting art curator.

Skene Catling de la Peña, led by architects Charlotte Skene Catling and Jaime de la Peña, covered the structure and a matching annex in lumps of flint stone.

The pieces of flint are arranged by colour to create a tonal gradient across the structure, and are a direct reference to the flint-filled soil and chalk that make up the local landscape.

"Described by judges as a marvel of geological evolution and construction, Flint House is a celebration of location, material and architectural design at its best," said a statement from the RIBA.

"The building rises from the ground as dark, fashioned flint and slowly changes in construction and texture until its refined white chalk blocks disappear into the sky."

Flint is a material rarely used in contemporary architecture, with the few exceptions including a London house with a flint wall.

Rough walls of flint also feature inside the home, while the roof rises up from the ground in a series of steps and cut-away balconies.

"Whilst defined by its flint construction, the project is home to an intriguing and intelligent mixed application of rooftops, terraces and recesses that combine to deliver a stunning piece of liveable, provoking, modern architecture that marries into the earthly yet beautiful countryside," added the RIBA.

The building was selected from a seven-strong shortlist, revealed over the course of the House of the Year TV series.

The Mill, a contemporary home by WT Architecture converted from an old stone mill building, was revealed as the seventh finalist in last night's show shortly before the overall winner was announced.

The prize was founded in 2001 and was formerly known as the Manser Medal and announced as part of the Stirling Prize ceremony, but was rebranded this year to suit the new televised format. Last year's winner was Stormy Castle by Loyn & Co Architects, a Welsh stone barn extended with contemporary concrete and steel additions.

Judges for 2015 included architects James Manser, Chris Loyn, the recipient of the 2014 award, and Mary Duggan, co-founder of Duggan Morris.

Duggan recently told Dezeen that smartphones and tablets were changing the way houses were being designed in the UK, spelling the end for open-plan living. A number of the homes on the House of the Year shortlist feature nooks, studies and smaller private spaces instead of one large open living area.

"Modern technology has consequences to our traditional living patterns and routines, and we are adapting to what is on offer," Duggan told Dezeen.

The full shortlist for the RIBA House of the Year:

» Flint House, Buckinghamshire by Skene Catling De La Pena

» Kew House, London by Piercy&Company

» Levring House, London by Jamie Fobert Architects

» Maghera, County Down by McGonigle McGrath

» The Mill, Scottish Borders by WT Architecture

» Sussex House, West Sussex by Wilkinson King Architects

» Vaulted House, London by vPPR Architects