Steve Collins was a few thousand feet in the air above Nepal when the worst earthquake in 80 years hit the country on 25 April last year. He had lived in Kathmandu for a couple of years but was on his way to a meeting in the Middle East, and didn't hear of the earthquake until he landed in Dubai. Once there, he received a message saying his wife and two children – who were sheltering in a church in the capital – were safe.

Thousands of others weren't so lucky.

The 7.8 magnitude quake killed almost 9,000 people, and some 600,000 houses were destroyed. The country has struggled to get back on its feet, and around four million people are still living in sub-standard temporary shelters. While donors pledged more than $4 billion in the aftermath of the disaster, much of that money remains unspent. Nepal's National Reconstruction Authority wasn't set up until seven months after the earthquake and the government has so far failed to help rebuild a single home, leading the British government to resort to giving aid directly to rebuilding projects.

Christian development agency Tearfund, meanwhile, will tomorrow become the first international NGO to complete an earthquake-resistant house in Makwanpur, a remote community a few hours outside Kathmandu.

In an interview with Christian Today, Collins, Tearfund's Head of Asia, explained that traditional Nepalese houses are made with very heavy walls and held together with cement, often with heavy tiles on the roof. "If and when they come crashing down, they really come crashing down," he said. "And they have big cracks in the wall even if they're still standing, so they don't feel safe."

Tearfund has therefore spent the last year training more than 300 local masons in how to incorporate resistant building techniques into traditional styles. The first house will be finished on Tuesday, and there are plans for 639 in total. There is a shortage of skilled labourers in Nepal, and so the newly-trained masons will go a long way in being able to share their skills with the wider community.

"It's been an encouraging sign that people who have gone through terrible circumstances have got something within themselves to use," Collins said. "You could see this as almost giving people a sense of purpose, a sense of dignity, even a sense of joy in some circumstances of being able to step out and do something, when before they would have been waiting for help from the outside. That help is still needed, but this community cohesion is in place to allow them to do stuff on their own".

One of the most remarkable consequences of the earthquake has been the way communities have overcome previous divisions to work together. Nepal has a predominantly Hindu population, and Christians – as a minority – often face persecution, though the country's church is the fastest growing in the world. Before the earthquake struck, members of either faith didn't have much to do with one another, but in working together to rebuild their communities, those relationships have begun to be restored.

Pastor Prajwak Thakuri, who leads a church in Makwanpur, told Tearfund that the rebuilding efforts have opened up doors in his community. His church has initiated a 'Sangasangai' (meaning 'together') initiative, where they seek to practically meet the needs of those around them. They've worked alongside other locals to rebuild a path that connects their village to the main road, meaning they are no longer cut off from surrounding communities, and are hoping to create a water source for everyone to use.

"The work with the community has been really positive. Before the Sangasangai group, the community didn't have much to do with us here and very few people would let Christians into their house," pastor Prajwak said. "This has given us a way forward to work together, and to change the way the community sees us and begins to accept us."

"We're seeing people step out and take proactive action," Collins added. "And they're empowered and equipped to do that... In a sense, it's difficult to say there is good coming out of it [the earthquake], because there is so much suffering, but God is able to work in such a crisis as this... and the earthquake has brought visibility to the role that churches can play in their communities.

"We're hearing more and more stories of churches doing things in their communities off their own back. Tearfund's partners have been working with churches, looking at the Bible and seeing what Jesus' ministry was. It wasn't just bringing people to the Lord, it had a practical side, so it's widening people's vision and understanding of their role a disciples. Going beyond the church walls and into communities."

There are concerns other than building sustainable housing, of course. Thousands of children were left vulnerable to trafficking – already a huge issue in Nepal – after the earthquake struck; many were orphaned, and others were sold by parents desperate for their children to have a better life abroad. A Sun investigation earlier this year found that Nepalese children were being trafficked into the UK. Tearfund has also therefore been involved in the creation of safe spaces for at-risk children, and raising awareness of trafficking in schools and communities.

Collins is adamant that Nepal has a bright future. "There's still a lot of hope," he said. The rebuilding will go ahead a lot faster now masons have been trained and agreements are in place, he added, and the long process of replacing destroyed infrastructure is beginning. The door has also been opened to improve disaster planning for the future.

The UK's international development minister, Desmond Swayne, earlier this month reaffirmed Britain's commitment to long-term recovery in Nepal. "Recovering from a disaster is a huge task and it can take decades for countries to properly mend," he said. "The building season in Nepal has now begun."

Collins agreed, and said the church, especially, will find its calling in being a source of light for broken communities. The rigid caste system in Nepal means that people are connecting with the message that God loves you whoever you are, he said, and the persecution Christians have faced means the decision to follow Jesus is not taken lightly.

"People really do have personal relationships with the Lord, and that enthusiasm is now spilling out as people understand the church, its mission and its role in society," he explained. "It's spilling out into the physical and the social aspects of life – people are really serious about what they do, and want to serve in the wider community."