A funny “story” (“storey” in the UK) has nothing to do with the floor of abuilding, but there are jokes.
 
“You’re wondering about the floor in my building where we go to tell jokes? Funny storey…” was posted on Twitter by his Henry James on October 2, 2011. “‘Funny story.’ ~ Architect pointing out the slightly leaning 4th floor” was posted on Twitter by Bruce Weighin’ on January 25, 2013. “Y’know, as an architect, I often get asked why one floor in my buildings always looks strange. Funny storey…” was posted on Twitter by Chris de Mercado on November 4, 2016.
 
“asks did you hear about the beautiful hotel where clowns rented out an entire floor all to themselves? Pretty funny story” was posted on Twitter by fnordy1 on October 6, 2018. “Hotel Manager: Did you rent the entire second floor to clowns? Me: It’s actually a pretty funny story” was posted on Twitter by Adam Cerious on October 1, 2019, and again on Twitter on December 2, 2020.
   
   
Wiktionary: storey
Alternative forms
. story (US)
Noun
storey (plural storeys)
1. (obsolete) A building; an edifice.
2. (Britain) A floor or level of a building or ship.
Synonyms: floor, level, story (US)
Coordinate term: deck
3. (typography) A vertical level in certain letters, such as a and g.
Usage notes
The terms floor, level, or deck are used in a similar way, except that it is usual to talk of a “14-storey building”, but “the 14th floor”. The floor at ground or street level is called the ground floor in many places. The words storey and floor exclude levels of the building that are not covered by a roof, such as the terrace on the top roof of many buildings.
               
Twitter
This Henry James
@thishenryjames
You’re wondering about the floor in my building where we go to tell jokes? Funny storey…
10:57 AM · Oct 2, 2011·TweetDeck
 
Twitter
Bruce Weighin’
@Lebla_
“Funny story.” ~ Architect pointing out the slightly leaning 4th floor.
6:58 AM · Jan 25, 2013·erased675638
 
Twitter
Alex McKie
@McFleaaa
”@utterben: Have you heard about the shopping centre with an entire floor dedicated to jokes? That’s a funny storey.” @ShopWhiteley giggles.
12:07 PM · May 17, 2013·Twitter for Android
 
Twitter
zoë bread
@zoebread
i know i really funny storey
  its the 3rd floor of my dads joke shop
3:34 PM · Aug 3, 2013·Twitter Web Client
 
Twitter
Purple Pickle ≡
@STFUdrazzyDGAF
3rd floor will be for Comedy Books Library, hahaa what a “funny Storey”
11:32 AM · Mar 23, 2014·Twitter for iPhone
 
Twitter
S
@mxyzptlk1
The second floor of the building was quite odd in comparison to the other floors. I guess that’s just the funny storey.
1:54 AM · Jun 12, 2014·Twitter for Android
 
Twitter
Chris de Mercado
@ChrisdeMercado
Y’know, as an architect, I often get asked why one floor in my buildings always looks strange.
Funny storey…
3:48 PM · Nov 4, 2016·Twitter Web Client
   
Twitter
fnordy1
@fnordy1
asks did you hear about the beautiful hotel where clowns rented out an entire floor all to themselves? Pretty funny story.
2:18 PM · Oct 6, 2018·Twitter Web Client
   
Twitter
Adam Cerious
@Browtweaten
Hotel Manager: Did you rent the entire second floor to clowns?
Me: It’s actually a pretty funny story
8:41 PM · Oct 1, 2019·Twitter for Android
 
Twitter
Adam Cerious
@Browtweaten
hotel manager: did you rent the entire second floor to clowns?
me: it’s actually a pretty funny story
8:15 PM · Dec 2, 2020·Twitter for Android
 
Adam Cerious@Browtweaten · Dec 2
Replying to @Browtweaten
manager: kinda weird how only one of them has a car though
 
Twitter
Diogenes was the only good philosopher
@BackToMac1
Replying to
@ohh_hELLno
Story is sometimes used to refer to a floor of a building, so a funny story can be a humorous tale or a floor full of clowns
8:48 AM · Dec 3, 2020·Twitter for Android