Weight which can be supported by plaster board?

[JohnW2]

I am never happy with such statements. .... the words "up to" translate to "absolute expected maximum under any circumstances".
whereas "typically" xxx might well be more useful,

Slightly more useful, I suppose, but even "typically" obviously does not necessarily mean that it will support the weight stated 'under any circumstances'. "Typically" implies some sort of 'average' -and, as with all averages, there will be some below and some above that figure.

I think one has to accept that there are so many possible variations in 'circumstances' that any 'guidance' figures have to be regarded very cautiously - and, even if 'typical', I would personally want to keep well below (maybe no more than 50% of ?) the 'typical' weight-bearing capacity quoted!

 

[trojanhawrs]

"They are rated up to 30kg on single skinned plasterboard, 47kg on 25mm double skinned PB."

I am never happy with such statements.

the words "up to" translate to "absolute expected maximum under any circumstances".
whereas "typically" xxx might well be more useful, if a plasterboard of decent quality is held in place with sufficient fixings and hammered in correctly !!! so an "up to" figure does not give me much confidence at all. The number of times it is actually achieved might be between never and 10% for example.

If they said "typically rated to 50kg" people would hang 50kg and cry when it failed. I'm sure their 30kg is conservative but they obviously can't guarantee the condition of the wall

 

[JohnW2]

If they said "typically rated to 50kg" people would hang 50kg and cry when it failed.

I'm sure that some people would do that - but they are just silly and/or lacking in understanding.

As I wrote, 'typical' implies some sort of 'average' and it is in the nature of any average that there will be some iundividual figures below, and some above, that average.

It's at its silliest when the 'average' in question is a median. We so often see/hear statements of the form "half of X are below average" (where 'X' can be people, schools, hospitals, products or whatever). However, in the case of a median, such a statement is totally meaningless, since it is nothing more than a statement of the meaning of a median. Even if the 'average' is a mean or mode, much the same will be true if the distribition of actual values is fairly symettrical around the 'average'!

 

[FrodoOne]

What a strange name for a hollow wall anchor; however did that come about?

I wondered about that also and had to look it up.

I then discovered that that product is much the same as the "Hollow Wall Anchor",
sold here by Ramset

https://www.bunnings.com.au/ramset-16mm-hollow-wall-anchor-4-pack_p2264781

Also described as "Steel Expanding Bolt Cavity Fixing"
by Rawlplug

41670 | RawlPlug Steel Expanding Bolt Cavity Fixing, 12mm fixing hole diameter | RS

au.rs-online.com

 

[ebee]

If they said "typically rated to 50kg" people would hang 50kg and cry when it failed. I'm sure their 30kg is conservative but they obviously can't guarantee the condition of the wall

Well that is one viewpoint and fair go to you there may well in truth be some merit about that.
Indeed John`s mention that it might be some kind of "average" has some merit and yes I was thinking more along those lines too.
However, given the fact that I often can be heard to utter that "the word average might actually be the most dangerous word in the universe!" I do tend to shy away from using it and probably favour a more gentle word like "typical", it depends upon what we are trying to convey.

If we do use the word average and explain which "average" we actually intend to refer to and they we give numbers on all of the other "averages" and additional data such as standard deviations (both population standard and non population standard) etc etc then perhaps the word average becomes useful in our quest. Without all of that info then it can often become quite misleading, hence its use in newspaper headlines.

So we want a useful ball park figure than we can usualy feel relatively safe in being useful much of the time, "up to" or "average" or "typically" does not cut it! What word do we use?

PS - the words Minimum and Maximum are not always helpful and especially so when folk say things like "A maximum of 50 or 60" or "a minimum of 2 or 3" . What the hell do they mean by those terms, I asks meeself !!!

 

[ebee]

I suppose that the term "As a rule of thumb, if all things are approx good as we can reasonably expect, then we should find that these things can most often take around XXX Kg steady weight plus or minus YYY Kg , usually.

What a mouthful but it might be a useful indicator, we might even give oit a name like "Slodge" or "Stickey wicks" or something.

Probably more useful than up to or average or typical etc

 

[JohnW2]

Indeed John`s mention that it might be some kind of "average" has some merit and yes I was thinking more along those lines too.
However, given the fact that I often can be heard to utter that "the word average might actually be the most dangerous word in the universe!" I do tend to shy away from using it and probably favour a more gentle word like "typical", it depends upon what we are trying to convey.

Like it or not, I think that "typical"really is another way of referring to what, at least in everyday English, is just some sort of 'average'. However, I certainly agree that any sort of average is potentially very 'dangerous' (and often abused, deliberately or accidentally), particularly in relation to do not 'fully understand'

If we do use the word average and explain which "average" we actually intend to refer to and they we give numbers on all of the other "averages" and additional data such as standard deviations (both population standard and non population standard) etc etc then perhaps the word average becomes useful in our quest. Without all of that info then it can often become quite misleading, hence its use in newspaper headlines.

Yes, but it's all probabilistic, so carries the same risks of misunderstanding as I have been discussing. Even if we quoted a mean and standard deviation for the weight bearing capacity, that would still not preclude some items having lowere weight-bearing capacities than some people would be expected - with a Normal distribution (or something like it) about 16% of individual cases will be more than one SD below the mean, and some 2.5% will be more than 2 SDs below the mean. In fact, merely quoting a mean and SD does not give any information about the "minimum possible" - although extremely improbable, it could (statistically speaking) be 'near zero'

PS - the words Minimum and Maximum are not always helpful and especially so when folk say things like "A maximum of 50 or 60" or "a minimum of 2 or 3" . What the hell do they mean by those terms, I asks meeself !!!

A 'minimum' (or maximum) which offers more than one figure obviously makes no sense - but, even when there is just a single figure, such concepts theoretically do not exist in probabilistic situations - i.e. there is theoretically always going to be finite, albeit possibly very very very small, probability of any figure which is above zero and below infinity!

 

[JohnW2]

I suppose that the term "As a rule of thumb, if all things are approx good as we can reasonably expect, then we should find that these things can most often take around XXX Kg steady weight plus or minus YYY Kg , usually. ..... What a mouthful but it might be a useful indicator,

Most of that mouthful is just a complicated way of saying 'average'. The 'XXX plus or minus YYY' is the potentially useful bit but, as I've just written, it is of limited value, because it is probabilistic - i.e. there will still be a possibility (finite probability) that it could not take XXX-YYY or that it could take more than XXX+YYY.

we might even give oit a name like "Slodge" or "Stickey wicks" or something.

Concepts like "95% confidence intervals" are very widely used, but still have the problem described above. For example, with a Normal distribution,about 2.5% of individual items will be below, and about 2.5% of them above, a "95% confidence interval.

Probably more useful than up to or average or typical etc

Any 'additional information' is obviously useful, but see the reservations I've mentioned above (which are always going to be present)

 

[foxhole]

Plasterboard will take a lot of static weight , my son in law while helping me in a loft stood between the joists on the plasterboard ceiling, it was a fee minutes before I spotted his error and asked him to carefully step back up to the joists. He was around 13stone .

 

[SUNRAY]

So no help then.


Stretching credibility a little.


I did ask the poster.

The internet does not seem to have anywhere recognising it as a noun.


Thanks for your help.

I had never heard the term before I read your post.
I Googled the word - nothing relevant.
I Googled 'interset fixings' and it showed a site which led to me discovering they were hollow wall anchors.

That prompted my perfectly reasonable question:


Even if I had heard the term before and knew all about them, my question is still valid.


Do people know what you mean when you tell them you will interset their light to the ceiling?

Apologies for the delay but other commitments yada yada...

So I searced the internet and this is the entirety of the top of the results

Which I believe provides an instant:
noun in the form of the name of a product made by Ralwplug
and adjective at the bottom of the screen

Further

The Merrium-Webster entry takes me to

and the 'How to use an interset screw?' entry takes me to a plethora of descriptions including YT videos, many (possibly most) describe setting the product.

I feel these pages are fully sufficient to explain the meaning of the word, why the product's adopted name makes sense, who makes it and where it is expanded (interset within the hollow wall).

So not a strange name at all.

So hopefully that has Henry'd up the mess.

 

[SUNRAY]

Plasterboard will take a lot of static weight , my son in law while helping me in a loft stood between the joists on the plasterboard ceiling, it was a fee minutes before I spotted his error and asked him to carefully step back up to the joists. He was around 13stone .

Wow that really was lucky, I'd seriously not expect a PB ceiling to support that weight at one point, many many years ago a friend stored his tools in the loft and whilst moving thing around stood a 14lb sledge hammer on the PB, several days later it came through. It split the board so a relatively small hole, it really surprised me.

 

[EFLImpudence]

...

So, you don't know why it is called what it is.

I don't see any of that product information when I search the name.

 

[ebee]

Plasterboard will take a lot of static weight , my son in law while helping me in a loft stood between the joists on the plasterboard ceiling, it was a fee minutes before I spotted his error and asked him to carefully step back up to the joists. He was around 13stone .

I do not doubt what you say but I do not doubt it could have easily gone the other way instead, some of the jobs I see then plasterboards in some areas and other things too can be held up by not very much more than willpower alone.

 

[ebee]

Most of that mouthful is just a complicated way of saying 'average'. The 'XXX plus or minus YYY' is the potentially useful bit but, as I've just written, it is of limited value, because it is probabilistic - i.e. there will still be a possibility (finite probability) that it could not take XXX-YYY or that it could take more than XXX+YYY.

Concepts like "95% confidence intervals" are very widely used, but still have the problem described above. For example, with a Normal distribution,about 2.5% of individual items will be below, and about 2.5% of them above, a "95% confidence interval.

Any 'additional information' is obviously useful, but see the reservations I've mentioned above (which are always going to be present)

John I pretty much a agree with all that you have said but I am always wary of "up to" etc as an advertising ploy and some folk do misuse it, when looking for a realistic norm that can be relied upon to some extent it does not easily give confidence

 

[SUNRAY]

So, you don't know why it is called what it is.

Because it's interset within a wall seems to he totally obvious to me now I have bothered to look it up

I don't see any of that product information when I search the name.

Those 'print screens' are totally genuine and full screen, the very top of the search results. Sadly google doesn't give you useful results where you are. Perhaps no one there bothers making proper fixings into PB there, which would feel strange to me.
Please draw a line under it now to prevent any more of your strange behavior wasting another 2 pages, Thank you.