query on joists from a nooby

[justanoob]

Hi All,
I have only just about to qualify to be a sparky but still a few things a need to ask about as my tutor may have been just a robot and when it come to ans questions he seemed to have no idea. so anyway he mentioned that holes in a joist need to be 50mm from top and bottom but he said if the joist is not big enough than you can buy these steel plates that just knock on but i cant seem to find any on the net anywhere. so was wondering if someone has ever heard of these. thank you in advance.

 

[onions1066]

Why wouldn't your joist be big enough, you won't find a floor joist any smaller than 7 by 2 in normal circumstances, maybe when you come across old buildings but I would tackle that when it arises, I wouldn't spend too long looking for them

 

[Octopus]

TLC sell them

 

[colshaws]

Try these Protecta Safe Plate Pack of 20 | Screwfix.com

 

[onions1066]

Try these Protecta Safe Plate Pack of 20 | Screwfix.com

Aren't they for protecting over joists I think he is wanting to strengthen the joist

 

[telectrix]

i read it as he wanted to know about protector plates for when yo have to notch the joists, like on a landing in a terrace house where the joists are 3"x2". or in an attic that's to be boarded.

 

[justanoob]

thank you for the ans was great help thanx again

 

[onions1066]

Well I read that wrong! Thought it was a weird question.

 

[justanoob]

guess it was a wierd question but i just wanted to clear it up as im new and wasnt sure if these metal plates was ok to use and keep within regs n things. cheers

 

[onions1066]

guess it was a wierd question but i just wanted to clear it up as im new and wasnt sure if these metal plates was ok to use and keep within regs n things. cheers

No your question actually wasnt weird how I interpreted it was

 

[Guitarist]

It's a shame more "electricians" don't protect cables they've notched in. Get sick of the number of cables on display when ever I pull back a floorboard.

The only query I'd have about those plates mentioned is whether they actually comply. I read somewhere that they should be 3mm or thicker and they don't look to be.

 

[onions1066]

We very rarely notch only if absolutely necessary but if we do we use 3mm plate steel as a min, the flimsy things fromscrewfix wouldn't stop a nail by the look of them

 

[Guitarist]

Made me laugh when my Elecsa assessor asked me the maximum hole size I could make in a joist, considering that many plumbers just remove half the joist to lay their central heating pipes in.

 

[justanoob]

so them flimsy things screwfix sell are really no use putting them on? do regs say that these can be used if joist is not big enough to leave 50mm i been thru the regs book but cant see nothing on these.

 

[Guitarist]

so them flimsy things screwfix sell are really no use putting them on? do regs say that these can be used if joist is not big enough to leave 50mm i been thru the regs book but cant see nothing on these.

You need to refrain from using double negatives

 

[justanoob]

what you mean guitarist ??

 

[derek]

"Can't see nothing" implies you can see something. It can cause misunderstandings.

 

[TaffyDuck]

I never cut no notches in no joists.

 

[justanoob]

i dont cut notches in neither i just simply asked if these plates are ok if there is not 50mm from either side when i put an hole in the joist are the plates ok under regs etc etc. not nitpicking about the wording i use if i was asking on my punctuation and grammer then i would use an appropriate forum not an electricians forum. cheers

 

[telectrix]

how to win friends on a forum. :hanged:

 

[ayjay]

o,hh such simple stuff

 

[justanoob]

i know i have just read it back and not sound good sorry ppl it wasnt meant how it sounded im crap at this writing lark as you my have guessed lol, just trying to get my head around this and cant see in the regs about the metal plates to see if they are ok to use or just a waste of time, money and are not even recognised as things to use when the joist thru hole is gunna be less than 50mm either side. cheers

 

[onions1066]

Why would the hole be less than 50mm if you've drilled it
?

- - - Updated - - -

o,hh such simple stuff

Oi ayjay no

 

[trev]

Never mind mate, continue to come here and we'll have you talking like Mr Cholmondley Warner in no time at all, it's all part of the service

One of my sons things was double negatives- I haven't got no money for example. Used to boil my wee, so I killed him.

 

[onions1066]

I won't tell anyone trev don't worry

 

[Stroppy]

I think a metal plate would be perfectly acceptable to protect a cable less than 50mm from the edge of a joist. If you think you can hammer a nail or put a screw through the flimsy ones then you need thicker ones (or a lighter hammer!)

 

[onions1066]

I think a metal plate would be perfectly acceptable to protect a cable less than 50mm from the edge of a joist. If you think you can hammer a nail or put a screw through the flimsy ones then you need thicker ones (or a lighter hammer!)

Or a shorter nail

- - - Updated - - -

I think a metal plate would be perfectly acceptable to protect a cable less than 50mm from the edge of a joist. If you think you can hammer a nail or put a screw through the flimsy ones then you need thicker ones (or a lighter hammer!)

Or a shorter nail

 

[justanoob]

Why would the hole be less than 50mm if you've drilled it
?

onions i mean like e.g if i say drill a 25mm hole in the middle of a joist thats around 100mm which would leave 37.5mm at top and bottom something like that if this makes sense i asked tutor this question and he just said use these plates but i wasnt convinced that these would meet regs etc so i asked on here.

 

[Des 56]

The regs book likely wont tell you what you should use,you wont find the solution in there in a hurry
It may tell you that a cable has to be mechanically protected from nails or AK 47 rifle bullets or weeping women but not what to do about it

 

[onions1066]

How many 4inch floor joists do you come across? Not many

 

[telectrix]

well, the weeping women is easy... duct tape.

 

[ayjay]

mayby nail a plate to the posters skull?

 

[kingeri]

Why wouldn't your joist be big enough, you won't find a floor joist any smaller than 7 by 2 in normal circumstances, maybe when you come across old buildings but I would tackle that when it arises, I wouldn't spend too long looking for them

Around my way there are loads and loads, go through stacks of steel plates on rewires. You have to either drill too close to the ceiling or the floorboards. If working from above I just drill through 5cm (ish) from the ceiling and pop a steel protector on. I'd never, ever notch out though. Never have, never will.

 

[Guitarist]

i dont cut notches in neither i just simply asked if these plates are ok if there is not 50mm from either side when i put an hole in the joist are the plates ok under regs etc etc. not nitpicking about the wording i use if i was asking on my punctuation and grammer then i would use an appropriate forum not an electricians forum. cheers

Electricians are allowed to speak properly too, you know....

 

[telectrix]

and it's "either " and "grammar",just to name a couple.

 

[telectrix]

Electricians are allowed to speak properly too, you know....

even in norfolk.LOL. :speechless::rofl:

 

[SPARTYKUS]

Favourite double negative:

"how are you today, sir?"

"not too bad"


ffs "GOOD then just GOOD"

 

[Guitarist]

even in norfolk.LOL. :speechless::rofl:

I didn't say it was compulsory...

 

[justanoob]

ok all thank you for all your comments very much appreciated