In a condo with a 50 cm drop down ceiling, and the area seems to be non vented.  Any steps I should take to seal or insulate the space?

You have the floor of a condo above?

Well unless you are getting some airborne sound transmission I wouldnt do anything with it.

 

With a narrow plenum like that adding insulation batts could be awkward especially around any light fittings which you wouldnt want to get overheated.

8 hours ago, moontang said:

In a condo with a 50 cm drop down ceiling, and the area seems to be non vented.  Any steps I should take to seal or insulate the space?

It very much depends on the construction of the ceiling.

2 hours ago, sometimewoodworker said:

It very much depends on the construction of the ceiling.

Cieling tiles are 50 x 50 cm, with the netal framing and a pretty sturdy installation from the early 90s.  Has about six light "cans.". High floor makes it hotter, but hasn't been bad..comfortwise or ac bill..rarely hear them above.

29 minutes ago, moontang said:

Cieling tiles are 50 x 50 cm, with the netal framing and a pretty sturdy installation from the early 90s.  Has about six light "cans.". High floor makes it hotter, but hasn't been bad..comfortwise or ac bill..rarely hear them above.

Without seeing it sounds like the ceiling is helping already with insulating floor above, if the lights emit heat change them for cool lights. 

2 hours ago, moontang said:

Cieling tiles are 50 x 50 cm, with the netal framing and a pretty sturdy installation from the early 90s.  Has about six light "cans.". High floor makes it hotter, but hasn't been bad..comfortwise or ac bill..rarely hear them above.

It sounds like a very standard inexpensive ceiling and as such is quite simple to add insulation (though if there is any point depends on how much heat is being radiated from above) you can buy cut squares of insulation that is silvered on both sides. that are just placed on top of the ceiling tiles.

 

We did that in our bedroom in our old house and it made a very significant difference, but then above the bedroom ceiling is a blue sheet metal roof.

 

You can't effectively do much else without doing very much more work, apart from replacing any lights with good quality LED's 

 

 

I also considered venting it into the pipe shaft.

If the ceiling does not get warm to the touch (heat source) and no noise problems, then it is not necessary to insulate or vent it.  If the lights get hot, swap them out with LED.

1 hour ago, moontang said:

I also considered venting it into the pipe shaft.

You mean knock a hole through the fire break in your ceiling space into the common area pipe shaft? 

34 minutes ago, Fruit Trader said:

You mean knock a hole through the fire break in your ceiling space into the common area pipe shaft? 

Basically..I have seen many similar units with a wall fan in the bathroom that vents to the shaft.

28 minutes ago, moontang said:

Basically..I have seen many similar units with a wall fan in the bathroom that vents to the shaft.

Oh ok, I guess thats the green light then.

2 hours ago, Fruit Trader said:

Oh ok, I guess thats the green light then.

You make a good point, but I don't think those are considered true fire walls that should never be breached, and of course many with the fans could he wrong, too.  Will take a closer look.