[W. K. Lis]

So what screws do you use to mount drywall then? If the answer is drywall screws then the question is, why would they be acceptable for drywall but not for plywood? They are similar in weight, size and thickness. If anything they will work better with plywood than drywall because it doesn't weaken if you over tighten the way drywall does.



Of course I don't. If you read what I wrote I was demonstrating that using a product for the purpose for which is is not designed will give you poor results. In this case hitting half installed screws with a hammer breaking them does not accurately reflect how they do the job for which they are designed.



Obvious to you and me perhaps, but there's plenty of people who don't have any handyman type skills who will take advice like this as valid. I dare say many people reading this thread have never even heard of a toggle bolt, never mind what they are.

Drywall screws are for attaching drywall to studs, period.

 

[Wooba]

Drywall screws are for attaching drywall to studs, period.

And Plywood. They don't make plywood specific screws. But they are not for any other purpose.

 

[Tuscani01]

For what its worth, I just had my TV professionally mounted, and toggle bolts through the steel studs were the recommended method. Turns out there was concrete behind the drywall though, so we were able to skip that entirely by mounting right into the concrete.

 

[Wooba]

For what its worth, I just had my TV professionally mounted, and toggle bolts through the steel studs were the recommended method. Turns out there was concrete behind the drywall though, so we were able to skip that entirely by mounting right into the concrete.

There's certainly nothing wrong with doing it that way and it will be very strong. But I know from years of experience mounting stuff a hell of a lot heavier than a TV that it's overkill. If I were to mount things with that method in my job I would be laughed at and with a some bosses possibly laid off for wasting time. If you've got the time and you want peace of mind, by all means do it that way.
That said, in the example given previously I believe it was suggested to use 8 bolts which is absurd. 4 of them would probably hold up a washing machine with ease.

 

[Eug]

Tuscani01's professional mounters must be idiots then, cuz Wooba says so.

 

[Wooba]

Tuscani01's professional mounters must be idiots then, cuz Wooba says so.

Even though you strongly disagree with me I don't understand what would cause you give such a childish and inaccurate reply.

Firstly I never said anyone was an idiot. I also never said that doing it your method was wrong. I repeatedly stated it was effective but excessive and unnecessary. The only thing about what you said that I was negative towards what your suggestion to install 8 toggle bolts on a relatively small piece of plywood. I called it absurd, which it is. Considering that as per the manufacturers rating, 2 toggle bolts IN DRYWALL would be able to handle the weight of most modern TVs (not that I would ever recommend it) the suggestion of putting 8 of them through studs is completely laughable.

The TV installers opinion, like mine, is that - AN OPINION. Just like I can ask 2 different IT Professionals if I should keep my hard drive on all the time or if I should turn it off when not in use I can get 2 opposite Professional Opinions.

In my professional opinion, to mount a piece of plywood as you described can be done effectively and safely with drywall screws. I'll tell you what my opinion is based on. I work in a profession that can only be done in Ontario by those people who are licensed and by a registered apprentice. To obtain my license I had to go through a 5 year apprenticeship. I have had several hundred hours of in class training and continue to do so to this day. I have a decade of experience and have worked with hundreds of different men and women who went through the same process that I did. While I do not install TVs for a living I routinely install plywood onto walls to which I mount various pieces of equipment that are considerably heavier than your average TV. I know that 99.9% of the many others in my trade would agree with what I've been saying to you so I'm quite literally backing up what I'm saying with millions of hours of experience.

With no disrespect to the TV installer out there. It's a perfectly fine job but it does not require a license and one can legally call themselves a "professional TV installer" the day they begin their job. Forgive me if I don't hold a great deal of weight to their opinions.

Additionally I would suspect very much so that the installer Tuscani01 was talking to was referring to mounting a bracket directly to the wall. Quite honestly until I read your posting I would never have considered mounting a piece of plywood on the wall of my home because it would be so ugly and would extend the TV out of the wall at least half an inch. Unless it was in some sort of cavity such as above a fireplace I can't imagine a professional installer would suggest that either because many home owners would find that unacceptable. I know I would not accept that if I were getting a TV professionally installed. Based purely on the experience of installing the mount at my previous place I would say it's quite likely that many installs are in a situation where reaching 2 studs is not possible. I've already stated that I would prefer to cut open the wall and install plywood between the studs but if for some reason that was not an option and I only had one stud to work with it's quite possible that with some research I would have come across the toggle bolt through a stud idea and gone with it. However if I was able to mount to 2 separate studs I would not hesitate to do so and I would probably throw a toggle bolt in the centre through the drywall just for fun too.

Obviously you disagree with me on this issue and that's fine. I'm quite happy to debate the issue and I enjoy it. It's part of why I come here and forums like it. But please only give replies if you're going to be mature about it. Also please base your replies on what I actually said instead of what you think I said.

 

[Eug]

So, let's summarize the discussion:

You say nobody uses toggle bolts.
Surprised at your answer I look it up, and find two articles immediately on this subject that specifically recommend toggle bolts into metal studs, for this very purpose.
Then you say you asked around and you and your buddies have never heard of this.
Shortly afterwards another poster states that the people installing his TV was planning to use toggle bolts through metal studs, stating that was the recommended method.
You then say it'd work, but nonetheless people doing that would be laughed at and possibly fired.

So, no, you didn't specifically say they were "idiots". You only called them laughing stock.

Meanwhile with regards to drywall screws:

Popular Mechanics: The Screws You Need to Hang Kitchen Cabinets

It wasn't that long ago that many carpenters went merrily about their business, putting in cabinets with nothing more than drywall screws. These aren't designed for wood-to-wood fastening, especially for heavy, concentrated loads produced by a cabinetful of dishes and glassware. If someone has told you to use drywall screws, disregard that advice.

APA: Nails vs. screws for sheathing applications

Always use screws intended for structural assembly of wood structures. Drywall screws should not be used. They tend to be quite brittle and the heads may pop off.

I even found a mention of this posted online, from the Architectural Wood Institute. Section 1700, Installation Standards:

Quality Standards expressly do not permit the use of drywall screws for architectural cabinets and casework for any quality level (Premium, custom, or economy).

So forgive me if my confidence in your professional opinion about drywall screws is not high.

 

[Wooba]

Yes, and I stand by it. Nobody in the trades uses toggle bolts in this way that I've ever seen. This is as true right now as it was when I first posted it. It's a very expensive way to install things (ie. labour intensive) for things that don't need them. I have already agreed with you that toggle bolts would be stronger but since you've stated earlier that stronger is always better (or something like that) let's examine that.

If somehow we were able to do a load test on a piece of plywood mounted to the wall. One with 8 drywall screws on 2 studs and one with 8 toggle bolts through the studs as you suggested. Let's suppose (and I'm just picking numbers out of the air here) that the screw piece was able to hold 500 pounds and the toggle bolt one 5000 pounds. The required load is 50 pounds. The piece with a 500 pound load limit takes 30 seconds to install and the 5000 pound load limit piece takes 30 minutes to install. Is that worth the extra time? I don't think it is.

Thank you for the links. Not really relevant though are they? I stated previously that drywall screws are only for mounting drywall or plywood to studs, no other purpose. They make special screws for the purpose of mounting kitchen cabinets so if that's what I was doing those are the screws I would use. The wood backing in a kitchen cabinet does not behave in the same manor as plywood does. A tapered screw will sit nice and flush inside plywood but won't do the same on the backing of a cabinet. The screw will not be embedded fully so it will be obviously weaker. This goes back to the video link you posted earlier demonstrating the weakness of a drywall screw when used incorrectly, but this doesn't strengthen your argument against using them correctly any more than that did.

 

[Eug]

If somehow we were able to do a load test on a piece of plywood mounted to the wall. One with 8 drywall screws on 2 studs and one with 8 toggle bolts through the studs as you suggested. Let's suppose (and I'm just picking numbers out of the air here) that the screw piece was able to hold 500 pounds and the toggle bolt one 5000 pounds. The required load is 50 pounds. The piece with a 500 pound load limit takes 30 seconds to install and the 5000 pound load limit piece takes 30 minutes to install. Is that worth the extra time? I don't think it is.

I know you made those numbers up, but I find it interesting you chose them. I think it provides a clue as to where you're speaking from.

Yes, if you're flush mounting a 26" LED TV, yeah a 500 lb load rating at the wall is more than sufficient. However, the point which I made earlier in this thread, is that if you're mounting a large TV on an extendable TV mount, the load stresses are much, much greater. Some of these mounts extend outwards as much as 2.5 feet, and they may be frequently jostled by people adjusting the TV angles. It's basically a big lever, with an up to 3-digit lb weight at the end of it being moved around on a regular basis.

In that latter context, give your two choices, the only acceptable option IMO would be your second one. Your first option is at much higher risk of catastrophic failure.

 

[Wooba]

I know you made those numbers up, but I find it interesting you chose them. I think it provides a clue as to where you're speaking from.

Yes, if you're flush mounting a 26" LED TV, yeah a 500 lb load rating at the wall is more than sufficient. However, the point which I made earlier in this thread, is that if you're mounting a large TV on an extendable TV mount, the load stresses are much, much greater. Some of these mounts extend outwards as much as 2.5 feet, and they may be frequently jostled by people adjusting the TV angles. It's basically a big lever, with an up to 3-digit lb weight at the end of it being moved around on a regular basis.

In that latter context, give your two choices, the only acceptable option IMO would be your second one. Your first option is at much higher risk of catastrophic failure.

Plywood mounted to the wall behind an extendable mount? I think I just vomited into the back of my throat.
I understand your concern by I still believe, even with all that extra weight several screws would do the job fine.
Heck, since ascetics are of no concern go ahead and use the kitchen cabinet screws instead!

 

[doug]

putting in cabinets with nothing more than drywall screws. These aren't designed for wood-to-wood fastening,

There are drywall screws designed for steel studs an drywall screws designed for wood studs. You're not differentiating between the two. I suspect you're not aware of the difference. your reliance on the internet for 'facts' is cute too

 

[Eug]

There are drywall screws designed for steel studs an drywall screws designed for wood studs. You're not differentiating between the two. I suspect you're not aware of the difference. your reliance on the internet for 'facts' is cute too

Uh, that specific quote was talking about wood, not metal. It says it right in the quote. However, my point was that drywall screws in general are not recommended for hanging cabinets.

Maybe people should just use wood pallets.

 

[doug]

that specific quote was talking about wood, not metal.

So, basically, it's irrelevant in a thread about hanging things on steel stud supported drywall.

 

[Eug]

So, basically, it's irrelevant in a thread about hanging things on steel stud supported drywall.

Since you're making me spell it out, the point was about drywall screws in general:

Drywall screws for metal studs are not recommended for hanging things other than drywall on metal studs, just like drywall screws for wood studs are not recommended for hanging things other than drywall on wood studs.

 

[Eug]

BTW, when we hung our TV from our wood studs, we used the lag bolts that were included in the package. Lag bolts, not construction screws (and definitely not drywall screws) are what the TV mount manufacturers generally recommend for larger mounts on wood studs.