Some formed defensive positions around underground tunnels, others nervously guarded the greenhouses, and one brave squatter scaled a makeshift watchtower to catch an early glimpse of any mob-handed intruders.

Nearby, a 16-year-old girl chained herself to the gates while a human chain of protesters sang a piano-led rendition of the Drunken Sailor sea shanty with the chorus: "What shall we do with the nasty bailiff?"

They rose at dawn and, after tending to the vegetable patch for what might have been the last time, the 200 or so protesters prepared themselves for a potentially ugly standoff with the police and bailiffs.

But, as the clock struck 9am with no sign of the bailiffs, the tension evaporated. With the threat of eviction temporarily lifted, the clouds gave way to blue skies as the protesting pianist played "You are my sunshine".

Grow Heathrow is based on a half-acre plot of land in Sipson. Photograph: Martin Godwin for the Guardian

Having made the half-acre plot of land in Vineries Close, Sipson, their home since March 2010, the 15 squatters who live here are not prepared to give up their self-built homes just yet. They moved in four years ago in protest at plans to build a third runway at Heathrow airport, whose jet engines roar overhead as regular as clockwork, but now the once-disused slice of west London has been transformed into a self-sufficient community, selling produce in the local shop and running workshops on bike maintenance, DIY and sewing.

"It's overwhelming," says Linda Bennett, 64, a veteran of the Greenham Common women's peace camp protest against nuclear weapons in the 1980s. "The principle of Greenham Common is the same here. This is defending a way of life and it's about climate change. I've only stayed here one night and being a city woman it's a bit of a culture shock, but I believe it so strongly I try to adapt. It makes me want to give up my property and come live here."

Under the name Grow Heathrow, the squatters have gained support from local politicians and residents. But they have one powerful foe: businessman Imran Malik, who owns the land and who secured a high court order to evict the squatters. Malik has to date rebuffed the protesters' attempts to buy the land from him for £50,000 – an offer they say is above market value. The squatters were told by an intermediary that Malik had applied for the eviction notice from county court bailiffs and warned them to expect an early raid, amid sightings of suspicious looking cars in the area.

The businessman made a brief appearance at the site morning, armed only with a video camera to film the protesters. The Labour MP John McDonnell, a supporter of the protesters, handed Malik a letter urging him to discuss the issue with the residents.

Councillor Mo Khursheed, leader of the local Labour party, said the squatters had become an integral part of Sipson, a small village whose residents have expressed concern about the buy-up of land and property in anticipation of a new runway. "They're doing things for the local community, you need these local activities. They're not harming anybody. I'm very pleased everything went peacefully. They will still try [to evict the squatters] but there's a long process, it's not very simple," he said.

Entertainment at the squatters' camp. Photograph: Martin Godwin for the Guardian

Behind the colourfully-decorated doors to the site, residents returned to normality beneath banners proclaiming "We are in it for the long haul" and "You can't evict an idea". Some sauntered around strumming guitars, while others slept on sofas and logs – a precious chance to rest after several sleepless nights fearing the prospect of eviction.

"It's pretty inspirational that people are carrying on as normal," said Dave Fuller, 33, a music publishing worker from east London who played the piano during Friday morning's "musical barricade". "When it's a place under threat, for people to come together and team up is pretty inspirational. Everybody's carrying on, life goes on, tThere's a lot to do and there are plans for the future but having an eviction hanging over your life is pretty stressful.'"

Scrawled on a job noticeboard advertising tasks such as digging out compost toilets, was a reminder of that ongoing threat. Alongside the telephone numbers of friendly solicitors was the message: "Write this on your arm in permanent marker". Residents had prepared themselves for the potential eviction with workshops on everything from digging tunnels, to legal matters, and a trauma support group for protesters involved in direct action.

Paddy Reynolds, 30, who has lived on the site for four years, evangelised about life in a self-sufficient community: "You get a bit more in touch with the elements and the seasons and the plants, which in itself is a bit painful because while you're getting in touch with the lovely wildlife, you're also hearing the roar of the motorway, the roar of the jet engines, tasting the fumes, seeing the people living out of London fly-tipping on your doorstep daily."

A Metropolitan police spokeswoman said there were no officers in attendance morning, but said they would be called to prevent a breach of the peace if bailiffs decided to return to the site in the future. A Heathrow spokeswoman declined to comment.