Drumroll, please: Riba House of the Year 2018 winner to be named on Grand Designs tonight - but which is your favourite from the shortlist?

The UK's best new home designed by an architect will finally be revealed in tonight's final episode of Channel 4's Grand Designs: House of the Year series.

For the past month, Kevin McCloud has been joined architect Damion Burrows and design expert Michelle Ogundehin to tour the 20 houses in the running for the top prize, judged by the Royal Institute of British Architects.

During each episode of the special four-part series, Kevin has revealed which two of the featured builds has been shortlisted. This evening, he will add the seventh and final property to that list, before announcing the overall champion.

The competition is tough, making for an unmissable episode, and as no-one's been told the result in advance you'll have to tune in to find out (9pm, Channel 4)

THE FINAL EPISODE: FOUR MORE HOMES IN THE RUNNING

Firstly, we're taken to explore four houses that all use materials in intriguing ways. In leafy Berkshire, there’s a perfectly-crafted timber 'box home' with sleek concrete floors and massive six-metre windows. Over in Surrey, a Thirties house has been completely revamped with a pale brick-and-glass modernist extension that blends beautifully into its setting, and in east London, an experimental 'makers' house' with exposed joists and steel lets craftsmanship take centre stage.

1. THE MAKERS' HOUSE, EAST LONDON

This four-bedroom new-build earned its name from the architects' commitment to hand-assembled materials and bespoke detailing.

Found within a short stroll of Victoria Park Village in Hackney, east London, it sits respectfully between its mid-Victorian neighbours, echoing their overhanging roofs. It instantly wows with its impeccably-crafted interior.

Spread over four storeys, the lower floors have a multi-level layout that cleverly designates different functions to the light-filled living space without breaking the flow. Exposed joists, brickwork and even netting give a unique feel to the room.

The petrol blue kitchen has been hand-built and three pivoting glass doors, two full-height, open onto a courtyard garden. Stairs lead down to the basement, where there is a cosy snug, larder and utility room.

Upstairs, big, naturally-lit landings are designed for displaying art. The master bedroom suite at the rear has its own study and dressing room, and a huge textured wall slides to reveal an open-plan bathroom.

The Rhodesian mahogany parquet flooring, reclaimed from Hove Fire Station in the Seventies, is a special highlight of the property.

2. BERKSHIRE HOUSE, CAVERSHAM

If you want a shining example of the early 21st century modern house style, look no further than this beautiful detached home next to the River Thames in Caversham, Berkshire.

"Every detail has been finely honed and every facade carefully composed", noted the judges, who praised the property's "faultless finesse" throughout.

The south side is largely glass and timber, filling the main living spaces and bedrooms with light. The double-height dining hall is particularly majestic.

The materials have been chosen to fit a muted palette of Scandinavian tones, from rough brick and pale-stained cedar through to marble and polished grey concrete. It's a minimalist's paradise.

3. No 37, BELFAST

Though modest in size, it's hard to miss this black timber-clad dwelling, which stands out from its brick-built community on the backstreets of the Ormeau Road in Belfast, Northern Ireland.

The building is split into two parts - one housing the tall living/dining/cooking space and the other the bathroom and bedroom.

This house may be small but it is not claustrophobic, thanks to views between the spaces and through to a garden.

There’s a fun playfulness to this design, as you can tell from the contrasting yellow doors and windows that nod to the massive shipbuilding cranes Samson and Goliath, visible from just outside the front door.

OATLANDS, SURREY

Hidden behind a Twenties suburban house in Weybridge, Surrey, is an asymmetrical rear extension and sunken garden pavilion, which connects the underused garden to the house and offers the opportunity to work peacefully without feeling too separate.

Light grey bricks have been used on the exterior and interior walls giving the building a solid sculptural quality that avoids fussy detailing.

The extension houses an open kitchen/dining space with a sitting area and reading nook lit by a wedge-shaped skylight, while a new master bedroom suite has been added above.

The new roofs have all been planted with wild grass to tie them in with the landscape.

So, which of the above do you reckon will earn the last spot on the shortlist?

THE SHORTLIST SO FAR:

Red House by 31/44 Architects, a "rebellious" end-of-terrace home in East Dulwich

Pheasants by Sarah Griffiths+ Amin Taha, a controversial glass and steel residence in Henley

Old Shed New House by Tonkin Liu, a farm shed turned contemporary home in New Yorkshire

Coastal House by 6a Architects, an elegantly modernised, 20th-century home in South Devon

VEX by Chance de Silva & Scanner, an experimental concrete house in Stoke Newington inspired by a 24-hour long piano piece

Lochside House by HaysomWardMiller Architects, an off-grid crofter's house in Scotland

Grand Designs: House of the Year airs tonight at 9pm on Channel 4