"below the first floor" is a correct and usable phrase in written English.
You could use it when referring to a certain level of a building, for example: "We were exploring the basement, which is one level below the first floor."
The steamfitter, whom he identified as Kevin Hunter, had been working in the boiler room, two levels below the first floor, trying to shut off steam pipes before the surge of cold water rolled in.
Steffens' world-famous reggae archives are housed in a labyrinthine maze below the first floor of his home in Echo Park, filling the entire lower level of seven rooms from floor to ceiling.
The closing of the original Islamic galleries in 2003 to make way for the enlargement of the Greek and Roman galleries below them on the first floor came at an awkward time, an almost symbolic displacement of Islamic by Western art in the wake of Sept. 11.
"So the people on the first floor below heard noises that sounded like 'bang, bang,' and as a result some of them ran out and created the chaos," Weissberg said.
Olga Berggolts, a well-known St . Petersburgwriter, described the misery eloquently in a 1960 work: "Sound carried in the house so ideally that if below, on the third floor, some people were playing blokhi or reading little poems, then on the fifth floor I could already hear everything, including the bad rhyming.
Another new element is Gordon Ramsay's first Prague restaurant, Maze, on the first floor, below.
The house has a two-bedroom mother-in-law suite with a full bathroom and a kitchenette on the first floor, below the main living area on the second floor.
The first floor, below ground, is a recreation room that includes a pool table and large-screen TV.
There are two stages and a rooftop patio called the Alley Deck, plus a historic bowling alley on the first floor below the club, if you're bored by the band's sound.
The second floor has a matching fenestration, with windows of equal value to those on the first floor below.
A slave girl in the house was allegedly thrown from the third floor landing to the first floor below and killed by a British soldier during the War of 1812, and eyewitnesses have reported hearing her scream.
