How to properly finish a floor above a join in extension

[Nozzle]

A question for the flooring guys - when you're working the first floor of an extension and you have to finish/cover where the brickwork transitions from the original part of an external wall into the flooring (incorporating joists/joist hangers), how do you make it a neat finish that can withstand movement in the house without eventually showing up through the carpet?

I'm reffering to this older thread I raised in the carpentry section:
http://www.diynot.com/diy/threads/sistering-joists.425258/#3329159

And before the carpet was rolled back, it looked like this after about two years (was flat when first layed)

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Nozzle

 

[ree]

I assume the extn on the LH the existing on the RH in pic 1?

I dont see any hangers - the extn joist tails appear to be sitting on a top plate.

Extn FFL's are designed in to meet the existing FFL's - which appears to have been the case.

There should have been no difficulty in meeting the two floors - perhaps a ripped board might be needed.

So why have you chosen to make the transition between two wood floors with some kind of compound?

The compound could cause future difficulties - perhaps moisture has swollen the adjacent boards? Perhaps the floor(s) have moved & pushed the compound up?

In pics 2. a joist is shown near copper pipes - the joist appears to be proud?

Without you lifting the carpet and exposing the floor its difficult to advise.

My above might be way off course but having glanced at & not understood your previous post, thats the best i can suggest?

 

[Nozzle]

Many thanks for your reply - to answer your questions in order

Yes, extension on left existing on right (with the exception of the carpeted photo where I'm standing in the existing to take photo)

Correct there are no hangers the joists sit directly on the bricks of the old external wall. It is an option for me to add some 90 deg brackets to firmly fix the joists to the brick, but it would be the brick 'crenelation' between each joist rather than anything below each joist. The carpet and flooring is currently lifted and I am trying to solve this problem before re-laying it.

I don't know what the acronym FFL stands for?

As for making the two floors meet is it best to cut back the cement by say 25mm then lay a board to make the floors meet?. The compound to which you refer is just cement poured in there by the original builders - to stabilise the loose material in the gap, to bring the level up and to provide a better transition where the floor boards in the old section and new section do not run in the same direction. The cement is quite thick in some places, and thin in others - this may have contributed to a crack. Or the weight of a nearby bath that also sits on the same old external wall.

The joist shown in pic 2 near the copper pipes is not proud, currently that also sits below some boarding where the original floorboards were cut back to the next joist to facilitate plumbing.

You are right to say the carpet is currently pulled back - my other thread in "carpentry" section reveals more about why.

http://www.diynot.com/diy/threads/sistering-joists.425258/

These photos are as found today, after I've done some work removing the old floor and moving some plumbing:
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Nozzle

 

[ree]

OP, i'm afraid that i'll move on from your post - i dont clearly understand whats happening, and therefore dont feel confident about offering advice.

 

[Nozzle]

No worries, thanks for the candid approach!

Nozzle