Is this lintel ok?

[cdbe]

It has been for 88 years (1930s semi with rosemary tiled roof). It is 170mm deep X 65mm. Above, but separated by a bed of mortar, is a 75mm x100m wall plate supporting the rafters and joists. I'm adding some new 7x2 ceiling joists sitting on the wall plate and 18mm chipboard flooring to provide loft storage (3-400kgs). Roof covering will be replaced in a few years (flat concrete tiles seem to be popular in the area - don't know whether these are heavier than the existing). I think I'll have problems if I leave it as is and I know if it was a full loft job it would need steel in. I'd rather not take it out as there's a big lead cavity tray nailed to the back of it so wonder if I can reinforce it with an angle iron or flitch plate.
While I appreciate it may be an SE question any suggestions would be appreciated. Thanks

Span is 1.76m.

Sorry the photos aren't great it's sunny here!

.

 

[tony1851]

OK for re-tiling in concrete, but if you were supporting a floor off it as well....?
Why not just reinforce with a 4 x 2 channel section bolted flat to the face?

 

[cdbe]

Thank you Tony, I thought it would need something. Channel would project beyond the finished wall as it's only about 25mm back from the plaster. Looking at steel sizes a 100x65x7 unequal angle should fit quite nicely so I'll fit one of those in.

 

[^woody^]

If its been up for 88 years, why would it be suddenly not OK?

 

[cdbe]

Hi, because I'm putting a new loft storage floor on top - and we have a lot of heavy junk and we can't get rid of it because the wife says we really need all of it, for ever!

 

[^woody^]

1.76m of timber lintel and the wall plate above it take anything you might be able to put in a loft.

 

[tony1851]

1.76m of timber lintel and the wall plate above it take anything you might be able to put in a loft.

'anything'?
depends on the span of the new joists, and the actual loading. If it's the accepted loft floor live load of 5lbs/ sq ft, then maybe OK,
if normal domestic loading of 30lbs..........?
The wall plate and beam will work separately, according to their I-value, so the wall plate will contribute little to the combination.

 

[^woody^]

'anything'?

Yes, anything that the OP is going to put into storage through the hatch of a 1930's semi.

 

[Doggit]

I just love it when you put things in to perspective Woody. Wish I had the same knack.

 

[tony1851]

I just love it when you put things in to perspective Woody. Wish I had the same knack.

Don't encourage him.

 

[stuart45]

If you store something in the loft you may as well throw it out.

 

[Doggit]

Two words; Christmas stuff.

But okay, throw everything else out.

 

[^woody^]

If you store something in the loft you may as well throw it out.

That's a bit harsh for those parents with mad hideous offspring.

 

[cdbe]

We tend to keep stuff for a few years till it acquires a patina of damp and mould then throw it away!

I apologise but I gave the wrong measurement for the span, it's 2.3m (the 1.76 was the big sealed unit). For my own peace of mind I've put a piece of angle iron in - £5 and half an hour's work.