Boiler cupboard removal

I don't know if anyone here is familiar with some 70s houses that have a floor-standing boiler in the center in a concrete 'cupboard', with a flue going up through the middle of the house.

The boiler and flue have long since been removed but I'm eyeing up removing the cupboard as well now, or at least the front wall of it to make a more useful storage space. At the moment there is just a low-level door for access (that I've taken off the hinges)

My concern is that some of the floor joists of the room above rest on the 'ceiling' of this cupboard, and they don't continue all the way to the opposite wall (there would have been no need as the cupboard ceiling and/or the front wall of the cupboard) would have supported them.

The cupboard ceiling seems to be composed of a series of strips of concrete, approx 120mm x 120mm as far as I can tell. Would these be pre-stressed concrete lintels? Can I be reasonably sure of this? When I look inside the cupboard at the front wall it has a high level opening which was previously an air vent. The joists for the floor above run perpendicular to this, so they would be sitting across the concrete lintels (if that's what they are).

So my plan is to cut an opening in the front, and tidy up the pipes inside, because removing the whole thing will involve extending the joists (structural engineer, building control application etc...?). I'm unsure if removing the front of the cupboard needs to be notified, any ideas?

Thanks for any advice.
S.

Some pictures:
https://www.diynot.com/diy/media/albums/cupboard.27186/

shagster, good evening.

In the second image posted, there appears to be some sort of "whitish" sort of foam like material ? does this material cover all the internal surface of the cupboard?

This material may?????? contain or be some sort of Asbestos??????

Can I suggest that you do some local research about the possibility of this material being Asbestos?

It was very common back in the day to chuck this material in especially in and around "heating systems" mostly the hot air type

As for the concrete "roof" that was probably installed as a positive fire break to the upper floor, if? the heating unit malfunctioned, the upper floor bedrooms would be to a certain degree protected.

Ken.

Good spot, but that's not foam, that's untidy mortar (the white paint was mine). Of course you can never know, so probably should wear a respirator when I cut it open just to be on the safe side.

What about the door, or door lining? They are normally AIB

As a quick check??

have you measured the floor to underside of the concrete inside the old C/H room as opposed to the floor to ceiling in the hall outside this enclosure?

Could be the concrete is resting on the walls and the upper floor joists either part rest on the concrete or span over the concrete??

Ken.

^woody^ said:

What about the door, or door lining? They are normally AIB

Click to expand...

That just went to the local refuse place a long time ago but I don't remember it being lined with anything.

KenGMac said:

As a quick check??
have you measured the floor to underside of the concrete inside the old C/H room as opposed to the floor to ceiling in the hall outside this enclosure?

Click to expand...

Yes, I certainly have, ceiling of boiler cupboard is about 120mm below ceiling outside. I can get my hand through a pipe hole in the top of the cupboard, and can confirm concrete is about 120mm thick. I can also just about touch one of the ceiling joists through this hole, that's why I know that the ceiling joist is resting on the cupboard.

KenGMac said:

Could be the concrete is resting on the walls and the upper floor joists either part rest on the concrete or span over the concrete??
Ken.

Click to expand...

Yes, that's about it:

So, in short, I am expecting (hoping?) that approximately 3 x 120x120 cross section lintels under that floor joist will be sufficient to continue supporting the floor above, and that it doesn't actually need the left-hand bit of cupboard wall.