What lies beneath...

[stevesee]

I'm a novice at DIY compared to many on here, judging by some informed replies I have seen in the forums, and am after some good advice now, if anyone can give it. I live in a a Victorian semi detached 2 up 2 down, ( built about 1870 ) and have recently discovered while doing some work that two centre joists for an upstairs room have been cut short about a foot from the party wall. The chimney breast for this room and the one below it have been removed at some point in the past. Between the two cut-short joists, someone has placed a noggin, and resting on this is an area of stonework which my neighbour suggested was part of the old hearth. It appears to be resting on this noggin. Whichever way I look at it, it's not right. I plan to pull up the floorboards and put two replacement joists in, and will just use the same size joists as they are now. The room spans just over 3.5m and I'm wondering whether to butt them into recesses or just affix floor joist hangers to the walls with 100mm bolts. I'm not sure whether to leave the existing cut joists as they are and just marry up the new ones next to them, so's I have minimal disruption to the ceiling below. The ceiling in the room below shows no signs of sagging, to me, and no cracks. The 'floating joists don't appear to have sagged to my untrained eye. It looks like it was done quite a while ago. Although it's probably been like it for a good few years, I want to sort it out as I don't like the idea of having my bed over two floating joists and maybe one day having the floor collapse under me. I really don't understand why twhoever did it just didn't put new joists in, and I don't see how there is no sagging from the 2 shortened joists, unless the noggins along their lengths are supporting it enough to give the impression of structural soundness underfoot.
Apologies for warbling on, and hope this is enough info. to be getting on with.

Thanks

 

[Deluks]

It's fine. The joists aren't 'floating' as they are attached to the noggin which itself is attached to the joists either side.
If it ain't broke...

 

[stevesee]

The noggin I mentioned only spans between the 2 cut short joists Are you saying that the other noggins along the rest of the length which I can't see are the ones which are supporting it sufficiently?

 

[stevesee]

Found these while surfing. I think these will do ( end repair ).

http://www.joist-repair.co.uk/Joist Repair Shop.htm?gclid=CO-2goWH-K4CFYImtAodNz56xA#Joists

That way I won't have to take up the whole floor and will have a strengthened one to boot.

 

[^woody^]

If this haas been like this for a while with no problems, then you could possibly assume that it is OK.

Have a search for timmer or trimmed joist, and see if this is what you have now. As I suspect by your description, that this may have been done.

 

[stevesee]

Woody, I have uploaded a pic of the offending area. The stone section you can see sits on a piece of wood that is nailed between the two 'floating joists'. I haven't taken up any more floorboards yet. What is a trimmer joist? Is it a joist that is attached at right angle to the floating joists and on to the uncut ones on either side? It might be staggered further back under the flooring. The one I can feel near the end of the cut joists seems to be attched just between the two floating joists, which would be no good. Either way, the ceiling doesn't seem to have sagged and is no less true than the other ceilings. It feels pretty sturdy anyway. The other problem is the fact that the last two floorboards nearest the wall span the good joists either side of the two cut ones and they are bouncy, having only two bits of wood crudely attached to the wall somehow, which give when I press down on them anyway.
Ideally, I'd want to take out the stonework resting on the middle noggin/trimmer joist (?) lengthen the cut joists with these end plates, and dig recesses int he wall if there aren't any there already from before the joists were cut. I had the floor up yesterday just to get an idea but will go back, take exact measurements and some more floorboards up.
Do you think I could do a decent job just by marrying a length of joist to each of the existing joists with bolts/screws and supporting it at the wall with joist hangers? The room is 11 1/2 foot span, so how far along the existing joist should I marry up as a minimum, as I'm looking at the method of the two involving the least upheaval. Sorry this is so long, but I hope it explains the situation, Woody.

 

[handyman77]

The photo isnt much good!

 

[stevesee]

Agreed. Anyway, I've decided to marry one joist to each shortened joist with M12 bolts, square washers for the ends and dog toothed washers between the two joists, to stop movement. This way I won't destroy the ceiling having to sleeve in a repair plate.
The span is 11 1/2 ft. How far should I double up?