Because of limited head room in the basement I am finishing, I would like to attach the sheetrock as close to the ductwork as possible. Can it span a 30″ horizontal distance unsupported? Or can I screw or glue it right to the ducts?
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I am going to say no to both.
More no on the duct thing.
Remodeling Contractor just on the other side of the Glass City
Can it span a 30" horizontal distance unsupported?
5/8" sheetrock shouldn't sag noticeably over a 30" span, unless there will be high humidity in that area. I would not recommend fastening the sheetrock to the ductwork. The ductwork should be suspended above the sheetrock, no contact.
Agree with the other posts, bad idea!
Why? I'm not saying there are not any good reasons, but what may they be? I did do this once on a basement remodel about 3 years ago. It worked well at the time, and having seen the project recently, there is no cracking at seams / corners. I can't say I was hugely comfortable with the idea, but I couldn't think of any really good reasons why it wouldn't work. There was a supply / return alongside each other, no room for a drop support between them, and about 36 - 37" from one side to the other. We did reinforce the attachments for the duct work to the joists.Anytime someone says something is a bad idea, I like to know what their reasoning is. Sometimes they don't have any real good reasons, it's just a gut response. Sometimes I have to say "duh, why didn't I think about that? Makes sense to me."
Here are some more good reasons not to screw SR to the ducts.1) The screw points will collect filth and increase the duct's friction resistance to air flow.2) Noise, already mentioned, but really important.3) Temperature differential could cause spotting at the screw heads due to condensation. (This is for AC.)4) The Mission: Impossible guys will injure themselves on the screw points while crawling through the ducts.Bill
ALL good points!
It could be attached to steel stud material either side of that spann and glued to the duct.
But I would not advise it. The reason for the duct is to carry heated air presumably so there woiuld be a fair amt of thermal movement leding to cracking the sr finish.
It would only ost you another half inch to 3/4" to use hat track channel to fasten the SR to and separate it from direct contact
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It is generally not acceptable to suspend one infrastructure system from another infrastructure system, it is best if each infrastructure system is hung to the buldings structural components that have been designed to carry the load. It also separates differentials of expansion/contraction, and noise transmission potentials.
If the sheet metal installer hung his metal to account for only the weight of his system then your additional drywall weight may adversely effect the ability of the ductwork to remain in position as originally installed.
One step further....the next owner of your home assumes the drywall ceiling will be able to handle some added light fixtures or a kids swing, or a boxing bag, or potted plant hangers....etc, etc.
The mention of the metal stud and hat chanel hung from the joist is the better method.
.....................Iron Helix
You might be able to glue it to the duct, but I wouldn't. You definitely can't screw it to the duct, and I would be a little nervous about spanning 30" unsupported. If you can find some 3/4" rock, that would probably span the distance.
What I did in a similar situation was to buy some of the smallest angle iron Home Depot sells. The inner portion of the flanges is about 1/2" or a little more. I then bought some 1x2 lumber and attached the angle iron to one edge of the 1x2 with short screws. That gave me furring strips that were stiffened up by the angle iron. It reduced the ceiling height by nearly an inch, but it worked well and has stayed flat over the last 5 years.
We had duct work against the wall in one of our bedrooms (side of a soffit). I tore it open and shifted it over an inch to give it space. The direct contact made quite of noise, and now is reduced quite a bit.
I have had peole ask me to do this. I suggest you accept the rational people are giving you. Building what I call a ladder as a framework it quick and easy. There are enough things to worry about at night. JMO Mike L.
Why not span it with plywood first then screw sheetrock to the plywood.
Not a bad idea, but space the plywood about 1/8" from the duct to reduce noise.George Patterson
Thanks all for the good input. Plenty of valid arguments for not attaching it to the duct. I might try the plywood idea.
CAGIV, thanks for recognizing that I'm over my head. I desperatly need help. When can you stop by?
Not in Chicago anymore unfortunately ;)
Stop by here and ask away, anyone here will be happy to help.
What concerns me is you may do something that would be dangerous to yourself or your family and not know it. Grant it, in a basement there isn't much, but stuff like hidden electrical connections, not putting electrical connections in a box, putting to much on one circuit, not providing combustion air for mechanicals etc.
Taunton has a pretty decent book on basement finishing:
Remodeling a Basement (Build Like A Pro)
as well as other publications to address other issues.
Give yourself credit for realizing that there was a question to be addressed. Many people wouldn't have.
I'd say you had a good gut feeling and didn't ignore it.
Good luck and know that we now expect pictures!!! buic
no for both questions, Please do not take this the wrong way but are you sure you are capable of finishing the basement by yourself?
The main two reasons for not gluing would be rattles and heat damage to the paint. Re the rattles, if the drywall were WELL glued, with a heat-tolerant adhesive (hard to find), it shouldn't be a problem, but if the gluing is incomplete or the glue joint separates in places you'll get the rattles. Hard to say how bad the heat effect on the paint would be -- certainly some light colors would tend to yellow.
The weight problem can be easily handled (assuming this is standard galv rectangular duct) by simply making sure that every section of duct is fully supported, adding more straps as needed.
Can it span a 30" horizontal distance unsupported?
Might, but it will not likely ever be counted as "pretty"
Or can I screw or glue it right to the ducts?
Only if like drywall that alternates whistling and cracking.
Duct work flexes. Not so much the temperature change as the physical mass of the air pused through it. Drywall will show cracks being bent to only l/360, which for 30" span is a bit strong on 1/16" (tad weak on 3/32").
Much, much better to frame on the flat underneath to a good, stout, furr-down partition. A person could make a case for galvanized framing, and going up a size (like to 20 or 22ga) to get a stiffer bit of 1 1/2" deep framing. Or not; framers differ.
Rich
I built a soffit like this to cover duct in a basement apt. you only lose a little bit of headroomunder the soffit and you'll end up no problems caused by gluing or screwing into the duct
zeeya
communication will be the source of your knowledge
no on both...
use T metal grid to limit the amount of loss headroom...
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On a different note, I had a similar situation. I used 1/2" birch ply and it spanned from framing to framing over the duct no problem. kept it away about a 1/4" for noise (solid born). the duct was also wrapped in inulation. you made no mention of that. just curious.
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