I would say that the fact is 'saving' is singular and 'savings' is plural. This dictates the verb that follows. You could say A saving of $20 is ... or Savings of $20 are ...
A basement bathroom can be built for about $15,200, Fred estimates. Of that, plumbing is the largest component. These prices are based on costs for a small bath measuring about 6 by 8 feet, with 8-foot ceilings. However, many basements are limited to a 7-foot ceiling. Another potential cost-saving location for a new bathroom is the attic.
Ask the Builder estimates that room additions cost $115 to $200 per square foot as of 2014, putting the cost of a basic 10-by-10-foot bedroom between $11,500 and $20,000.onverting an unfinished attic to a 15-by-15-foot bedroom with small bath costs an average of $49,438, with a nearly 85 percent return on investment, according to a 2014 report by Remodeling. The cost of this bedroom conversion can be as much as 30 percent higher in high cost-of-living areas.