(Please note that in certain situations,  what ,  when , and  where  can function as relative pronouns.) Relative pronouns introduce relative clauses, which are a type of dependent clause. Relative clauses modify a word, phrase, or idea in the main clause.
The 2014 Survey of Construction (SOC) from the Census Bureau shows that the average completion time of a single-family house is around 7 months, which usually includes around 25 days from authorization to start and another 6 months to finish the construction.
Q: How long does it take to move a house? A: Generally the entire process of moving or raising the home and building the new foundation is completed in one or two weeks. Weather conditions, our schedule and the masonry contractor's schedule must be taken into consideration however. A: Moves are charged by the size of the house and degree of difficulty.