[Engineering] What Type of Lintel is this? How long can it be?

[bromster]

Hi Everybody,

I want to completely remove a double wall inside my house. The span of the room is 4700mm. The wall supports the 4.7m gable wall of the front of the house. If I go into the garage, I can see 2 lintels / concrete beams already running along that wall. I have attached a photo of how it looks.





Each of the 2 lintels seems to have a height of 70mm and a width of 115mm (The same as the bricks above it). It also has what seems to be concrete filling a cavity between the 2 lintels, as well as 2 pieces of rebar running through each lintel.

Does anyone know what this type of support beam is called? If so, does a 6.2m span (4.7m + 1.5m overhang into garage as pictured) seem possible for this type of beam? I have been into the roof and checked along the ceiling line and there is a concrete-coloured row running the entire length of the wall, but I can't be sure. I would like to avoid casting a new beam if I can.

Thanks.

 

[twaatie]

That does not look right , they have the wall supported by the truss. Did you check that the plans where correct by council ?

 

[AntennaMan]

Get a structural engineer out to have a look, rather than depending on the opinion of random people on the internet.

Remember, advice on the internet is worth exactly as much as you pay for it.

 

[web]

As a "builder"come civils person those pictures are wrong on so many levels, those are normal brick lintels that are used above windows and door what they have done there is not too clever, although I can't see the whole design.

Generally "I want to completely remove a double wall inside my house" this not a good idea without getting a structural engineer to have a look, as double walls are usually (nearly always if they are internal walls) load bearing walls. You can span the area with a beam but get it checked out first by someone qualified as once your roof sags you will be up the creek without a paddle.

 

[ThinkCentre]

Get a civil engineer! Just one thing, the bricks on top of the lintel also helps holding the structure up!

 

[bromster]

Understood. Thanks everyone. The truss in pic is a second set of trusses because the garage has its own pitched roof. Perhaps the load on these trusses was low, so they tied the lintel into one. I dunno. But considering that it is clearly not straightforward, engineer is definitely the way to go. I might end up putting 2 Timber Beams or an I Beam in just to be safe.

The lintel looks well reinforced though, which is why I asked.

 

[falcon786]

Coming from an engineering and construction background I can safely say your pictures don't have enough detail in them to make any form of informed call on the way forward.

Rather get somebody in the field to have an on site inspection and take it from there, don't try to save a grand or two and then have problems later on that could cost you much more,not to mention safety concerns.

Which area are you in?

 

[BlindMelonChitlin]

That does not look right , they have the wall supported by the truss. Did you check that the plans where correct by council ?

:wtf:
Where do you see that?
I see a Lintol with a truss below it. A lintol is a steel reinforced concrete beam effectively. How do you figure the wood beneath it is supporting it?

That said, I'd hazard a guess that the builder 'made a plan' with a cheaper solution of 2x lintols instead of a full width reinforced concrete support beam. I doubt it would give you any grief, depending on how high the wall is. It may not be within acceptable engineering specs though - I don't know. There's not a lot jutting out by the looks - maybe 600mm at most.

What's on the other side of that roof?

 

[Bulldog_imported]

An absolute masterpiece! Clearly the roof has not made contact with the ground yet, all that with 50% of the structure supported (as I could see in the photos) - it seems somewhat dodgy mate, best you call someone in construction. I am a mechanical engineer and can't quite fathom why it was built like that.

 

[Bulldog_imported]

P.s. don't remove the retaining wall u less you want a dusty longe

 

[savage]

The span you're talking about is very long. I have two places with about a 4.7m span that I wanted to open up (load bearing, with the roof on top), and in both cases I had to find a way around it (by not removing supporting walls).

Even IF an engineer OKs it, the work (labor) involved to do this would be astronomical. It's not as simple as just knocking the wall out. You have to temporarily support the weights (load) while you work too. It's a very, very costly (and dangerous) exercise.

 

[TEXTILE GUY]

Get a structural engineer out to have a look, rather than depending on the opinion of random people on the internet.

Remember, advice on the internet is worth exactly as much as you pay for it.

I wont be taking that advice ...... Got it on the internet .... and Google is watching ......

 

[Spizz]

First of all, get an engineer in to have a look at it before you do anything. But just FYI and if it helps you understand a bit, then I'm a civil engineer and with what information you have given, it's pretty sure that this was not done to a conventional design. Obviously someone has had a bright idea and made it 'work'

That's not to say it's not safe or fit for purpose though. Maybe I'm reading and seeing the pictures wrong, but that looks like a 6.2m length 'beam' with a 1.5m cantilever poking into the garage?

So then it's all about the support for the beam and the load on top which we obviously can't see in the pics apart from the brick work shown. I think I can imagine though from your description.

If was about safety, I'd say leave it as it is because it looks fine from here as the load is obviously distributed evenly on the beam itself. Without seeing the support then I can't comment on it but it's there now and it's presumably been there for a while so it looks like jobs a good 'un. If the support is the actual wall you want to remove under the 'beam' and there are no columns involved, I'd say not a chance. That lintel sitting on two concrete columns with a smallish amount of brickwork on top might be ok (but still not advisable), but again I'd need to have a look to see as the picture is incomplete and I'm assuming a lot.

As it is, they have used a couple of lintels wrongly and loaded the cavity with concrete making it pretty heavy. Of course of the wall under it is the same, then no probs. But if you want to remove the wall, then that is a seriously big red flag.

So of course you need someone to come and advise you. But at a glance I'd say if you are doing what I think you are, you'll need to take the whole wall down from top to bottom and cast an in situ concrete beam.

Actually, in my house I extended through a wall a couple of years ago and used a hefty RSJ type H beam as support across a 10m span. There are alternatives and solutions but get in a qualified structural engineer to have a look and advise.

But I hope that helps you at lest a little in the meantime.

 

[Wasabee!]

Get a structural engineer out to have a look, rather than depending on the opinion of random people on the internet.

Remember, advice on the internet is worth exactly as much as you pay for it.

Best advice.

 

[brakpanpolisie]

I think its called a grout filled beam or cavity wall, usually done to span garage openings if I remember correctly. Check the link : https://law.resource.org/pub/za/ibr/za.sans.10400.k.2011.pdf From about page 65 thereabouts. Definitely consult a structural engineer before thinking about clobbering that wall