Ken, when I installed one at church I used all thread rods from the purlins, and used a 3/8 Inch steel plate to hole the fan box. The rods I used were also 3/8 inch. Put up 2 in the kitchen and nary a bit of wobble.
[This message has been edited by spkjpr (edited 03-04-2003).]
#22810 - 03/04/0311:20 PMRe: paddle fans in suspended ceilings
Yup..We usually use a caddy T-bar hanger to for the box and then support it from the structure with all-thread.Most times,the fan location doesn't line up with the bar joists so deep unistrut is used to bridge between the joists and the allthread is supported from the unistrut.
#22811 - 03/05/0308:10 PMRe: paddle fans in suspended ceilings
We have used a suspended ceiling fan box kit made by someone (Can't remember who) that clips to the grid as usual but comes with a length of dog chain and a turn buckle.
We've used them to hang pretty heavy chandeliers in jewelery stores.
The framing above the ceiling was bar joists so you just wrap the chain through two bar joists (one on each side of the box) the take up the tension with the turn buckle until the chain is supporting the weight of the fixture.
Never used it for ceiling fans but it does make for a pretty solid installation... not to mention fast and inexpensive.
[This message has been edited by master66 (edited 03-05-2003).]
#22812 - 03/05/0309:06 PMRe: paddle fans in suspended ceilings
Back when I was doing "inside" work. We had the same problem. It seems like we bought some kits like master66 described. Ken, I would call your local supply house, and they should be able to find something for you.