"Folk club" has a different meaning in the US than in the UK. In the UK it seems to refer to a location that sponsors folk gatherings. In the US it refers to a group of people who like to gather for folk music, concerts/and or sings. I have been seeking out sings for almost 60 years (I'm in my 70s).
1964-68 Cornell Univ in Ithaca NY
       There was a Cornell Folksong Society, but they were into bluegrass at the time, and a group of people would congregate in the Outing Club cabin most Friday nights to sing. I come to that group.

1971 or 2 - 1975 Salt City Song Miners in Syracuse, NY. The concerts had a location, but the sings moved from house to house, a common arrangement here (our houses tend to run larger than the older homes in the UK)

1979-2013 various groups
    Princeton (NJ) Folk Music Society had a concert venue, but sings moved from house to house
    Dick Levine had a long-standing group that moved from house to house on the (New) Jersey shore
    Branford (CT) Folk Music Society had a concert venue, but sings were held at two houses
    Mudcat gatherings, mostly at Annap's and WYSIWYG's
    Rich Kaufman had an annual gathering at his cabin summers
    Dick Greenhaus and I sponsored sings at our house in NJ when we lived there.
    Meetup groups I hosted for Sea Shanty and Folk Music Appreciation (I inherited that one) and Trad Folk in the Northern Suburbs (I started that)
    several others we got to occasionally in NJ, NY, CT
    I keep trying to start one in my retirement community, but with little success so far.