· Houses can sink into ground when not in use · Fears over environmental impact of building boom

Removing blots from the landscape could become far easier thanks to an improbable vanishing act conjured up by a team of Irish architects: their houses simply disappear into the ground.

Tackling "bungalow blight" is a priority in an increasingly wealthy country desperate to preserve its tourist industry but littered with more and more second homes. The single-storey dwellings being developed by two County Donegal architects, Antoin and Tarla MacGabhann, could provide the solution, satisfying rural planners and environmental campaigners, as well as those who admire ever-changing coastal views.

The radical plans for the ultimate in eco-friendly, holiday homes will be unveiled at the Venice Biennale architecture exhibition this weekend, demonstrating how seaside bungalows can be lowered down and remain out of sight when not in use. Sheep might even be able to graze on their submerged, grass-topped roofs.

The Tideaways scheme will also enable the houses to rise and fall gently with the tide, repeatedly shifting the occupants' perspective. The design exploits hydraulic technology already used in coastal homes in the Netherlands and the houses could be assembled for as little as €150,000 (about £100,000), the architects suggest.

This subterranean sleight of hand is a response to public concern about the way Ireland's finest scenery is being destroyed by a runaway building boom. A third of all homes put up since 1995 have been outside big towns, a response to the demand for rural lifestyles. Donegal county council has limited the number of developments permitted for those who do not live locally. In bleak winter months the countryside is deserted but left scarred by the presence of holiday homes. "We have an issue about growing suburbanisation, living on the land and overuse of cars," Antoin MacGabhann, who works in Letterkenny, said. "We are looking at how we might relieve some of these pressures.

"We can't just eat up the land the way we have been doing it. We are thinking of taking up smaller blocks of land and concealing the homes when not in use."

The Tideaways designs refined by the MacGabhanns envisage rows of three terraces on the coast located inside existing communities. The first row would float on pontoons and could be towed to a harbour when unoccupied. The row behind would rise and fall, on hydraulic rams, with the tide; in winter they could be sunk down to ground level, disappearing into the landscape.

The third row would be permanent and would provide homes for long-term residents of the village. The houses, timber or metal-framed, would be mainly two bedroom bungalows.

"Our inspiration came from looking at how the land is used on Tory Island [off the Donegal coast] where everyone is allowed access to the sea," Mr MacGabhann said. "We need to share land more than we do now.

"Our model would ensure there was less impact on the landscape and better planning in villages. We have not built these yet but the Irish government has been very supportive.

"The proliferation of holiday homes has the potential to destroy the very landscape that attracts people in the first place. Despite being in use only 10-20% of the year, these buildings are visible 100% of the time."

There are already 200,000 second or holiday homes in the Republic of Ireland, approximately one for every 20 people.

Tideaways is one of nine Irish projects that will be on display at the Venice Biennale architecture exhibition from Sunday. They have a common theme, demonstrating how an increasingly suburban island might be transformed into a "super-rural" island by 2030.