The 20 houses vying for this year's RIBA House of the Year award have been announced, including a forest home for a pair of artists, a London residence covered in mirrors and a cluster of cabins in Dungeness (+ slideshow).

A renovated mid-century house in Wiltshire, a house-cum-gallery in Brighton and a Japanese-inspired house extension also feature on the longlist for the RIBA's annual award, which recognises the best UK house designs of the past 12 months.

Other additions include a house with a rooftop garden pyramid, a fort-like residence in Jersey, a stone and zinc country house in Cumbria, a house that hangs over a cliff in Cornwall and a small faceted extension to a Yorkshire home.

Formerly known as the Manser Medal, the prize was renamed RIBA House of the Year in 2015.

It now forms the basis for a spinoff of the television series Grand Designs, presented by Kevin McCloud, with the shortlist and winner announced over four episodes.

Last year's winner was a house clad in pieces of flint, designed by Skene Catling de la Pena for one of the world's richest families.

Other past winners include an extended Welsh stone barn, a south London house with translucent glass walls and an extension to a mill-keeper's house on the Norfolk Broads.

Scroll down for the full list of projects vying for the RIBA House of the Year 2016 award:

» Ansty Plum; Wiltshire, England, by Coppin Dockray
» Contemporary lean-to; Harrogate, Yorkshire, England, by Doma Architects
» Contour House; Baslow, Derbyshire, England, by Sanei Hopkins Architects
» Covert House; Clapham Old Town, London, England, by DSDHA
» Edge Hill; Darras Hall, Newcastle upon Tyne, England, by Sutherland Hussey Harris

» Garden House; Hackney, London, England, by Hayhurst and Co
» House of Trace; Lewisham, London, England, by Tsuruta Architects
» Le Petit Fort; Jersey, Channel Islands, by Hudson Architects
» Modern Mews; London, England, by Coffey Architects
» Murphy House; Hart Street, Edinburgh, Scotland, by Richard Murphy Architects

» North Vat; Dungeness, Kent, England, by Rodic Davidson Architects
» Outhouse; Forest of Dean, Gloucestershire, England, by Loyn & Co
» Private house in Cumbria; Cumbria, England, by Bennetts Associates
» The Cheeran House; Reading, Berkshire, England, by John Pardey Architects
» The Narrow House; Brighton & Hove, England, by Sanei Hopkins Architects

» The Owers House; Feock, Cornwall, England, by John Pardey Architects
» House 19; Old Amersham, Buckinghamshire, England, by Jestico + Whiles
» Private House 1109; Cheshire, England, by GA Studio Architects
» Tin House; Shepherd's Bush, London, England, by Henning Stummel Architects
» Zinc-House; near Monikie, Angus, Scotland, byLJR+H Chartered Architects