LYNN – A Lynn war veteran who was denied a variance to build a hot tub and sauna to treat his military service syndrome in his garage has brought a lawsuit challenging the Board of Appeals unanimous decision.Michael D. Faiella, who resides at 25 Baltimore St. (also known as 30 Portland St.), filed the court action in Salem Superior Court against the city of Lynn Zoning Board, claiming their decision was “unlawful in procedure, made upon unlawful procedure based on error of law” and violated his constitutional provisions.Faiella wants to convert his garage to habitable space so he can have running water, a sauna with a hot tub, a greenhouse on the second story and a new shed dormer.Faiella bought the residence, containing 6,598 square feet, in 1997, which is located in an R2 General Residence District, according to the lawsuit.During the winter months of 2005 his two-car garage was destroyed during a storm.The following year he applied and received a building permit to reconstruct the two-car garage for a non-conforming structure, but earlier this year the Zoning Board restricted plumbing in the variance.Faiella states that his physician in 2005 and again in 2001 prescribed a hot tub and sauna to treat his military service-related syndrome from the Gulf War, according to the lawsuit.