Volunteers build houses with low-income families who have been chosen on the basis of need for adequate shelter.  Selected families must contribute 500 hours of sweat equity on the construction of the house which is then sold to them through a no profit, no interest mortgage.  From the time a family is selected, to the time the project is completed, can be as long as one and 1/2 years.  Do not need to be a citizen to apply but must be in country legally.