Understanding purpose of structural support of floor

[three-tees]

Hi,

I'm planning to utilise my basement space (previously a garage) however I'm in need of creating some additional ceiling height - especially where currently positioned there is an RSJ.

In summary, I want to remove it, and replace with wood in a similar arrangement to the rest of the house however I can't however understand fully why the RSJ is in situ, and was hoping someone may be able to help......

I've uploaded a few photos to help explain what is there.

Any insight out there? Any tips much appreciated


.

Cheers,
Tom

 

[foxhole]

Probably holding the house up .

 

[Deleted member 174758]

One thing I can say I'd that almost any timber used to replace a steel will be of greater section (depth). This is why even in listed buildings there is a tendency to replace rotted beams and beam ends with steel UBs unless they are a visual feature (although cost is also a factor). Stiffness derives from the depth of the UB or timber beam, so if you reduce the depth of that whatever is above it (e.g. floor, etc) is more likely to bounce (or worse) when you walk across it

One thing I am surprised by is that the steel hasn't been boxed in plasterboard or at least coated with Intumescent paint in a place like a garage (it's a fire resistance thing, although maybe just the environment I work in, though)

 

[tony1851]

Logic suggests it might be supporting something above, such as a wall?
If so,replacing it with an equivalent-strength timber beam will lower your headroom even more.

 

[Why Not Indeed]

One thing I am surprised by is that the steel hasn't been boxed in plasterboard

It was, he's pulled it off.

 

[cdbe]

You could probably reposition the beam higher up within the floor. If it's a blockwork wall on top the steel could take the place of the first course of blocks, you might even be able to strongboy it from below. Makes you wonder why it wasn't put in the floor in the first place.

 

[three-tees]

Thanks for your contribution everyone. To answer the first point, yes it was boxed in with paster board, for fire resistance - I dragged it down.

Second part - it isn't holder a wall on the first floor (floor only), however a point to note is that the block structure extends to the second floor, where there is a floor supporting the pitch of the roof.

The third part about the depth, what is odd is that the steel has timber (at 90 degrees) above it, holding up the floor in affect at 90 degrees. I've illustrated it.