Dan GrimmerAs a radiographer at the region's busiest hospital Shelley Johnston-Downing is not used to mixing cement or laying bricks but that is exactly what she has chosen to do - in one of the world's poorest countries.Dan Grimmer

As a radiographer at the region's busiest hospital Shelley Johnston-Downing is not used to mixing cement or laying bricks but that is exactly what she has chosen to do - in one of the world's poorest countries.

The 34-year-old, who specialises in MRI scans at the Norfolk and Norwich University Hospital, will be helping to build houses in El Salvador for two weeks as part of a large charitable project.

Ms Johnston-Downing, who lives in Britannia Road, Norwich, will be swapping her clinical clothes to work as a general labourer for Habitat for Humanity charity.

It is a worldwide non-profit housing organisation that works in partnership with people in need of decent housing to build and renovate simple, affordable homes.

El Salvador, in South America, has been struck by a series of natural disasters, including floods and hurricanes, over the past decade and housing needs are very high, particularly in rural areas.

She said she is 'excited and nervous' about the challenge.

'I have never done anything like this before,' she said. 'I was inspired by seeing some of the work the charity does and I have always been interested in Latin America.

'There are about eight volunteers and we will be working alongside skilled tradesmen. I have only ever done a bit of bad DIY before so it could be interesting - I will be mixing cement, laying bricks, you name it. I am happy to get stuck in and do whatever is needed.

'It will be such an interesting and rewarding experience. I am also aiming to raise �3,000 which will be ploughed back into the communities.

'If the trip is successful I would like to continue the work elsewhere. It is going to be a real challenge.'

Ms Johnston-Downing will be working in El Salvador, in urban and rural areas including San Salvador, La Paz and San Vicente , from July 10.

The basic 450-square-foot layout of the houses they will be building includes two bedrooms, living and dining areas, and either an outdoor latrine or a bathroom, if sewer services are available.

The houses are made of seismic-resistant concrete blocks and are structurally reinforced with steel to protect against the earthquakes that trouble the area.

A spokesman for the N&N said: 'This will clearly be a big change from Shelley's day job, but we admire her energy and commitment in undertaking such a demanding but worthwhile project in her spare time.

'We wish her luck and look forward to hearing all about it on her return.'

To sponsor Ms Johnston-Downing or get more details of her venture log onto http://www.mycharity.ie/event/shelley_elsalv/