The former head of the United Synagogue's Community Development Group - who was number 69 in this year's JC Power 100 - will also be undertaking consultancy work for the US and the London School of Jewish Studies.
JVN was set up last year by the Board of Deputies to help volunteers find suitable roles. "We want to be the one-stop shop for Jewish people to volunteer in the UK," Mrs Lewis said.
At LSJS, she will be "co-ordinating a project on social justice, the environment and other contemporary issues from a faith perspective.
"It includes a forthcoming course looking at world religions from a Jewish perspective."
For the US, she will review its policy on movable assets - for example, its archives - as well as helping to implement the recently announced closure of Hounslow, Heathrow and District Synagogue.
"All these complementary areas of work enable me to pursue my particular interests and to create and lead new projects, whilst working with others to define and develop activities and programmes that support and sustain the UK Jewish community," she said.
At the Chief Rabbi's Office, Mrs Lewis worked on interfaith initiatives as well as the Chief Rabbi's CD commemorating Israel's 60th anniversary, Home of Hope, along with the YouTube video promoting it.
US president Simon Hochhauser said she had laid the basis for "increased interfaith work by our whole community" and welcomed her continuing association "both with the work of the Chief Rabbi and with the US".