I would appreciate any thoughts on this.
It will probably involve you looking at my photographs. Please paste this into your browser.
I have completly removed a small chimney in my 1909 house. Removed from the loft (where it was already capped ) through a first floor bedroom and down to the corner of the kitchen where it housed a floor standing boiler.
The chimney (& hearth in first floor bedroom ) is removed , the old boiler removed and a new wall hung boiler installed in the kitchen.
I now wish to make good the 1st floor bedroom floor supports prior to arranging plastering.
I am giving thought as to how best go about this.
The joists in the bedroom run paralell to the width of the ex chimney breast.
The hole left by the chimey & hearth is bounded by
1.A trimmer ? to the right of the ex breast running from the wall (set into wall ) to the first full joist and butted to it . Meeting it at right angles. Fixing appears very solid but unclear how it is fixed to the joist. The short joists , at right angles to this are notched into it. ( and set into wall at other end )
- The first full joist . Running from wall to wall and presumably set into wall at both ends. ( In the photos this is not visable. It is under the overhanging floorboards which used to but up to the width of the heath )
- The external wall for the depth of the ex chimney + depth of ex hearth.
- The wall where the width of chimney used to be.
I presume the classic method would be to overlap & extend the 2 short joists run which parallel with the ex chimney. Extend them to the exterior wall & fix by brick to timber joist hangers motared into the wall.
But
Problem with this would be it would involve removing the trimmer , seems pretty solid & stable.
I could perhaps hang the joist extensions, with timber to timber joist hangers , from the trimmer. (and hang from external wall at other end ) ?
However, structurally, this worries me, as I would be hanging them from a short trimmer which is simply butted up to the first full joist. As I said appears solid but not clear how it is fixed. .
So I had thought best bet to
Fit the new short joists , at right angles to the main joists. Paralell with the trimmer . Hung from the first full joist at one end and from hangers mortared into the brickwork of the wall (boundary no 4 above) at the other. However I have read that , for new installations at least , joist hangers into brickwork need to have at least 3 courses of brickwork above them. While superficially this should not be a problem into this existing wall . A look at the close up photo will show that , at the level where the hangers would go , there is a ridge for most of the width of the ex chimney where the levels of the exposed wall are different between the bedroom and the kitchen below. This means that there will not be full courses above the hangers and if I add brickwork for this , it cannot be full width bricks . ( I will of couse have to brick up the dark sooted echimney cavity that can be seen in the photos.)
So what about a stout joist / baton bolted to the chimney wall , from which to hang the new short joists . (and to the first full joist at the other end ) ?
Another classic method , I imagine , would be to fit a timber framwork ( with short joists and noggins included ) which would fix to the 4 boundarys of the hole. My problem with this is
- I could not now properly fix one side of frame to external wall ( depth of ex chimney & hearth ) because of the pipwork that serves the new CH boiler .
What I hope I will not be hearing is that I have to completly repace the two short joists which run from the trimmer , the width of the room , to the far external wall. This would be very difficult because at the wall end they (and the floorboards)r go under a deep, built in wardrobe, which runs the whole length of that external wall.
Many thanks if you have persevered and managed to follow this.
Any thoughts much appreciated .
Richard . .