I was wondering how most guys attach medallions to ceilings. I just realized that after 15 years doing this, I never had to actually install the medallion and the fixtures I have replaced on them, I never even thought about how they attached the medallion to the ceiling. Any suggestion would be appreciated, I have 3 of these coming up in the next few weeks

adhesive, sheetrock screws and caulk.

Double sided foam tape works well, as does a construction adhesive like "liquid nails".

I carry a squeeze-tube of Liquid Nails on the truck with me just for this purpose. I've also used long sheetrock screws and used caulk to mask the screws.

I have used adhesive caulking and it worked fine. Make sure that you buy the right type that doesn't burn into the backside of the medallion though.

There are methods, and I think this one is best.... I have worked on many jobs where there were very large plaster castings for them. Some as big as 4'... (2-3' are common to Victorian homes - that are common here.) In the old days the plaster'er? would cut slots for "keys' to fit in both the casting, and the keyways of the lathe. (The space between the slats) But - In most of the jobs I have seen them done in (I've not had to hang them myself) they gouged the back of the casting with a grinder, sloped plaster on it and then screwed it to a piece of plywood that has metal lathe screwed to it, then mounted the plywood to the framing between the joists. After that sets, they lathe up to that and float it into the edges.

If you have a line laser... Place the medalion on the floor on your CL in the orientation you want. Then shoot the laser up to the edges of the framing, and transfer the line. Or go ol'skool and plumb-bob it... them mount it to ply sticking out each side in the method above. Then mount that to a blocks between the joists. Solid and fast...

One thing I have always had a problem with, is that one of the local companies that makes them here does reproduction work of older designs - originally made to fit a GAS lamp. (a hole 1 1/2" to work in) So a 3/0 ring will not fit in it, or be so deep that screws wont reach the box above. Some are 6-7" thick, like this one . So I make sure to be on site with the fixture so as to make sure the box can make it, and the fixture will cover what I force them to remove from the casting. Often I will need to do some severe head banging to get someone to grind out the back for a 4/0 box, with a 2" 4/0-3/0 mud ring with a crow-foot hickey inside mounted direct to the surface of the cieling framing, or even firred down more, or to the ply that goes between the joists.

Be wary though, the bigger the medalion, the bigger/heavier the fixture! A few years ago I had a customer throw me a loop, and had medalions installed, then showed me a 500 pound wrought iron fixture that needed to be hung with 1" all-thread. (They stole/bought it from some church in Spain as a candle chandelier and had it wired.) It was a Polish joke install - 3 people to steady it on a panel lift, and one guy to get told to hurry up and wire it....

Oh one more word, pre-drll the holes on the casting, and use thread-cutting screws like decks with the cut knotch, or tap-cons.

I can tell you one adhesive not to use ... that Locktite tube they advertize as having more "instantaneous" grip than anything else. It does have more quick grip but when it sets it's as brittle as peanut brittle. We put up a 24" hard foam medallion one day and came back the next to put up the fan. The medallion was solid until we had to enlarge the opening around the box screw holes. Good thing it wasn't plaster cause it popped off the ceiling and hit the floor. A small bit of Liquid nails was next and now you couldn't get that thing down if you wanted to.

We have found most foam medallions are warped, as are most drywall ceilings. The method we use is trim head drywall screws to stabilize the medallion and liquid nails to adhere. The trim head screws (Robertson) are easy to conceal. D'ONT drive them in too far. They will not hold the medallion to the ceiling, just keep it from falling.

Fnsane