You may be able to arrange an interest-free loan through your contractor as well. However, if you're unable to pay off an interest-free loan before the term expires, you’ll probably owe interest backdated to the day you signed the agreement. In this arrangement, make sure you don’t lose the right to withhold payments if the contractor's work isn't done to your satisfaction, if that was a term of your contract.
The catch is that to keep the 0% rate, you will likely be required to make minimum monthly payments on time every month, even during the 0% introductory period. You need a clear plan for repaying the full amount you borrow before the introductory period ends, or else you will have to pay interest on the remaining balance, usually at a much higher rate.

Many people turn to home improvement loans even though saving up and paying cash for home improvements is often the least expensive option. After all, when you pay cash, you don’t have to pay interest. However, sometimes home improvements come in the form of emergency repairs, and paying interest on a loan is less costly than saving up to pay cash while your roof leaks for months and causes mold, rot and damaged ceilings that will cost even more to repair later.
Interest rates. The less interest you pay, the more loan you can afford. An adjustable-rate mortgage (ARM) is one way to lower that rate, at least temporarily. Because lenders aren't locked into a fixed rate for 30 years, ARMs start off with much lower rates. But the rates can change every 6, 12, or 24 months thereafter. Most have yearly caps on increases and a ceiling on how high the rate climbs. But if rates climb quickly, so will your payments.