Load bearing Cavity wall removal

[EasterBern]

Hi all,

I'm looking to take out a load bearing cavity wall and put in 2 steel lintels.

I've had the lintels spec'd by Catnic, and the work has been approved by Building Control.

I'm thinking that I'll need to take out parts of the lathe and plaster ceiling to put needles through and then prop both sides.

It looks like needles aren't something that you can hire (unlike strongboys which seem to be readily available), but it looks like I should be able to use floor joists as the needles? Or what size timber should I use for needles?

And should the padstones cross the cavity or be separate for each leaf?

Thanks in advance,

Bern.

 

[^woody^]

Why not a single lintel? And why not a different style lintel from a different manufacturer which would be easier to fit and require less removal of masonry and less rebuilding?

Needles are as short as possible and can be from 75x75 or 100x100 timber or thinner and deeper. It all depends on how deep you want the holes to be, how many props you will use and the condition of the wall above.

Padstones are normally in accordance with the design calculations. But you don't need any for standard lintels under standard loading, and they would not normally span a cavity but may do if so designed.

 

[EasterBern]

Many thanks for the reply.

Building Control wanted me to specify which Lintels I was going to use, and suggested that I contact Catnic and use their Scheduling service. So I guess I'm tied to using the Lintels that they have specified. I suppose I could find something of an equal spec from someone else, but I'm quite happy to use the Catnic lintels.

They specified 2 lintels because they didn't make one for our cavity width. I'm quite happy with that as I assume each will be lighter and easier to manoeuvre than one larger one even if it means more work.

Nobody has specified that I use padstones, I just assumed that's what you did!!

Cheers.

 

[noseall]

but it looks like I should be able to use floor joists as the needles?

Yes, for one of the leaves of masonry. You could use strongies for the other.

However, the biggest headache is threading the steel beams in or at least having the steel already trapped in between the props - as you can see below.....

Needle 2_LI

• noseall
• 18 Apr 2021

 

[EasterBern]

That looks like what I imagined

So what is supporting the needles on the inside if you can use strongboys for one of the leaves?

 

[cdbe]

I did both skins with strong boys, because I'd just redone the room upstairs and didn't want to knock holes through the wall. Even less room to squeeze the steels in:

 

[noseall]

So what is supporting the needles on the inside if you can use strongboys for one of the leaves?

The bedroom floor and some acros undrneath

 

[lostinthelight]

The bedroom floor and some acros undrneath

Out of interest, what if the joists run parallel with the wall or are the needles above the floor resting on it?

 

[noseall]

Out of interest, what if the joists run parallel with the wall or are the needles above the floor resting on it?

The joists do run parallel with the wall and yes, the needles rest upon it.

Had the joists ran onto the wall, then fitting the beam at floor level (which we did) would not have been an option (without lots of work and effort). Plus the joists act as needles in that instance.

 

[EasterBern]

I guess if the floor joists go into the wall that's got to help.

And CDBE, that does look tight, I think I'm definitely going to go for needles!

Cheers all.