the ephraim smith house is an 1845 greek revival house in the village of sugar grove, illinois, united states. the house was built by ephraim smith, a millwright from vermont. it is the only example of a wood framed greek revival rural house in kane county that remains in its unaltered state. the house has, however, been moved from its original location. the ephraim smith house was added to the u.s. national register of historic places in 1980.