(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.
What should be included: 1  Concrete shouldn't be poured in temperatures lower than 40 degrees or higher 90 degrees Fahrenheit. Installing a typical foundation for a new home can take 2-3 weeks including time for curing the concrete, according to BobVila.com .