Suspended Ceiling and Duct Conflict

[Daves69]

Hey folks, looking for suggestions on install of grid ceiling for basement. I'm trying to keep as much headroom as possible in efforts to keep this from happening. It's a learn by do project.
How close can I get? I do realize I'll need to slide tiles in as I go. Is cutting a Main T height and Cross T's shorter an option for this or will they fold up on me? All comments welcome.
TIA.

 

[Bad Sport]

If I were doing it and was faced with that dilemma I might cut it ONLY where the duct is leaving enough room for the tile obviously and make little sheet metal tabs and attach the frame to the side of the duct using small self tapping screws just for the extra support. So you would screw the tab to the duct, twist it to line up with the frame and attach...............if that makes sense.

That is if I'm understanding correctly.

Is it worth it for an extra inch or so, I dunno, lol.

 

[Daves69]

Well, if the tin won't just fold up on me I feel it's worth the trouble. The T's are a thin double wall until they box out at the top 1/4" above the holes.
Ideally, I need almost 3/8" to be level with the house "I" beam, and that would remove the box plus a little more. That would put the grid at 78" from the concrete floor. Standard door heights are 80" I believe.

It's not an issue to attach hangers to the duct then?

BTW, I've moved the duct up as far as it would go already.

 

[Bad Sport]

It's not an issue to attach hangers to the duct then?

I wouldn't think so, you're not tying up the Queen Mary, lol. Pull down on the duct and see how it feels, as long as the duct is secure, and if in doubt throw another strap around the duct somewhere, and it should be fine.

Well, if the tin won't just fold up on me

Cut a piece and see what it feels like. You will still have a bit of the upright piece left....yes?

 

[nm9stheham]

I've spent years pulling and replacing tiles to do cabling for industrial systems. 2'x4' tile grids may well fold up if you cut them. How about going to 2'x2' tiles in that area to keep it stiffer? 3/8" and that top 'box' is most of the vertical strength.

Connect to the duct only as reinforcement to prevent twists and subsequent folding. Not much way to connect them to the duct unless you use some sort of angled tab. And the screws into the grids will interfere with the tiles so use #6 screws IMHO.

 

[Daves69]

Thanks guys!
Tried cutting the box area off a cross T (LOL). Took multiple cuts in both directions one snip/piece at a time. It wanted to cause the face end to twist. The box is just too stiff and will not curl with the snip like a flat sheet would. Took a while and got through it finally but it wasn't pretty. Covered the sharpies with some high speed aluminum tape (left side of picture).
So I tried cutting angled notches out of the box on the main T and bending the box over 90° (right side). It seems to have worked well enough (for who it's for so far) and I think I may try to use it to run a couple screws through to the duct and the panel still fits.

I had thought about 4' panels in the beginning but decided against as I knew it would be tight fitting. Even 2' panels can be a pain to get in or out with the clearance.
Trial fitting. Panel at top of picture is in the "adjusted" T's..………..

 

[4spdragtop]

Looks like you got it figured out Wayne. Heres our downstairs kitchen. 77 1/2" concrete floor to lowest part of duct.
Long bar ran parallel to duct. Perpendicular to joists. I screwed into duct on the support straps from joists.
Hope that helps.
Yours looks great!

 

[Bad Sport]

Took multiple cuts in both directions one snip/piece at a time.

No cut off wheel?

 

[Daves69]

Thanks Steve. I need to get off my …… and put in the final hangers before it all comes crashin' down. Then I'll either need to 90° or angle up above the window to the right of the lights. An angle might look better. Then too, it's a basement.

No cut off wheel?

Yeah, that actually crossed my mind more than once last night while whittling away, but the notch and bend kept me inside and warm, Lol. I'm going to do the next cross T with the cutoff and see how it goes.

 

[Bad Sport]

I'm going to do the next cross T with the cutoff and see how it goes.

A couple saw horses and a 2x4, 2x6 whatever you have, after cutting the rib at the top to desired depth, lay the piece on the edge of the board clamp it just beyond your cut on each end.

That should give you both hands to run the cutter accurately. Should turn out nice a clean.

 

[Daves69]

Should turn out nice a clean.

 

[Bad Sport]

Hey that looks better!

 

[Daves69]

Lol, I'll be happy when I don't have to see it at all!

 

[nm9stheham]

LOL... I can tell you are not an HVAC guy. To move the duct up more, they will literally remove/cut ANYTHING.... including the floor joists.... water pipes.... sewer pipes.... gas lines......ANYTHING is fair game LOL. You can tell we have had to repair our damaged lines cut by HVAC contractors in general construction.....

 

[Tooljunkie]

My plan is to box in the ductwork with good one side plywood,attatching to a framework beside the duct. Stain or paint to suit. 1/2” is all it takes up.

 

[383Scampman]

I installed acoustical ceilings for 12 years . Inorder to install the tile you need 2 3/4" clearance . anything less and you must install the tile b4 you inatall the cross tees . Takes 3x longer that way but sometimes you have no choise .

 

[67Dart273]

Figure out a way to support it from above. If the duct is not supported well, if you have to cut a hole in the duct so you can run a wire/ screw/ rod / whatever clear through the duct to a support above it

There is always a way LOL

 

[Daves69]

LOL... I can tell you are not an HVAC guy...…....

Ha, I'm only "filter changer" certified for that stuff. No cutting up floor joists for me. And I'm not looking to have the new kitchen island relocated to the basement!!

...anything less and you must install the tile b4 you inatall the cross tees . Takes 3x longer that way but sometimes you have no choise .

Yeah, I did expect to do that from the get go.

Figure out a way to support it from above. If the duct is not supported well...….,

I think I'm good on duct support. It's only a couple feet or so from the furnace and the hangers are close. Going to try a few screws into it.
It really wouldn't have been a that big a problem if they didn't put the intake so close to the output! (where have ya' heard that before) That bent main T is just a couple inches into the intake duct.
The initial picture shows the "end" of the intake on the left. The second picture is the reverse angle.

 

[nm9stheham]

Speaking of gird supports..... I'll digress with a story. We were running heavy coax in a hospital and came to a hall section where the grid looked a bit uneven. Ran the coax and when pulling a tile at the far end, part of the grid slipped down... then more slipped down, and all of a sudden the whole grid in that area was starting to sag and trying to fall. One of our guys held it up at a critical point, another warned folks to not enter, and I went for more help and spare grid wire.

After we stabilized it, we found that some guys running wifi cable had CUT OFF 2 OUT OF EVERY 3 GRID SUPPORT WIRES AND USED THE GRID SUPPORT WIRES FOR THEIR CABLE SUPPORTS. Good gawd, can you believe that ?!

The hospital maintenance guys said "Yeah, we know who that was....."

 

[bobscuda67]

Figure out a way to support it from above. If the duct is not supported well, if you have to cut a hole in the duct so you can run a wire/ screw/ rod / whatever clear through the duct to a support above it

There is always a way LOL

I hung on and off for 40 years and we never attached to duct work. Vibration from moving air makes a noisy ceiling.
I'd run the mains perpendicular to the duct for best rigidity. I've even installed mains every 2 feet instead of 4 on difficult layouts.
I agree, there is always a way.

 

[Daves69]

............….The hospital maintenance guys said "Yeah, we know who that was....."

Lol, I won't deny I've had folks tell me in the past, "if ya' do it like that you'll be talked about later".

..... Vibration from moving air makes a noisy ceiling. I'd run the mains perpendicular to the duct for best rigidity...…..

In my case, I'm screwing into the intake for this one main T around 4' length. I'm trying foam pads between T and duct. I also have some furniture base felt I could try. The adjacent main T's are wired to the joists properly. I'm thinking I'll get away with it.