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