Wood panel wall supporting landing base plate?

[tomos94]

Hi all, first post here (many more to come as I’ve just started my first renovation) and a complete amateur.

I’ve recently purchased a Victorian terrace (built 1900) in need of renovation throughout. One of the first things I had planned to do was take down a wooden panel wall between the stairs and the dining room.

The panel wall is nailed into the floorboards at the bottom and at the top it’s nailed to a piece of 2x4. This piece of 2x4 doesn’t run between two load bearing walls, it’s supported entirely by the panel wall. The floor joist supporting the landing floor runs right down the middle of the floorboards, so by losing the wall and the 2x4 would I be losing support to the edges of the floorboards and the landing base plate? Pictures attached.

If so, what could I do to avoid losing support to the floorboard edges and landing base plate?

Cheers,
Tom

[GALLERY=media, 107864]DC3250BC-D510-4A20-98DC-1F80704BDF43 by tomos94 posted 3 Apr 2022 at 10:31 AM[/GALLERY][GALLERY=media, 107863]831E5DFF-44AE-4B33-AB15-9C61955D59A9 by tomos94 posted 3 Apr 2022 at 10:31 AM[/GALLERY][GALLERY=media, 107862]04026C4C-A6C9-4199-97D4-269567F88730 by tomos94 posted 3 Apr 2022 at 10:31 AM[/GALLERY][GALLERY=media, 107861]2275644D-7EE6-4CD0-BC7D-D82D4594AB2F by tomos94 posted 3 Apr 2022 at 10:31 AM[/GALLERY]

 

[Deleted member 174758]

What concerns me most is that the short end of the stairwell opening has no trimmer, which needs to be there both to support the joists (which appear to just hang loose), tie the josit ends together and carry the edge of the floor.

AS A MATTER OF URGENCY YOU ABSOLUTELY MUST GET THAT AREA PROPPED ASAP. WITHOUT PROPPING THAT SECTION OF FLOOR MIGHT FAIL AT ANY TIME IF IT GETS HEAVILY LOADED. Ideally one or two Acrow props and a short scaffolding board one at top, screwed to the props, one at the bottom (ditto). Even a few lengths of 3 x 2 stud screwed together with a 2 to 3in thick piece of timber at the top (not 18mm ply) should suffice

Once it is safely propped you will need to cut back the joists to be in line and install a timber trimmer - same cross section as the joists behind it, but doubled up. So if your joists are 7 x 2in. your trimmer will need to be 7 x 4in which made up. RH end (viewed from top of stairs) needs to be pocketed into the wall, LH goes onto a double joist hanger (nailed in place with twist nails)

On the long side if possible knock off those little "joists" (I think they are just noggins) and put a single 4 x 3in in fixed into the existing joist, then screwed through from the top through the floorboards

How is the top of the stairs carried? Cannot see a trimmer there, either.

TBH this matchboarding was probably not done by a carpenter at all - otherwise I'd have expected to see a trimmer in there at the end of the opening

 

[tomos94]

Thanks for the reply Job&Knock - I have a couple of acrows so will get it propped up for now. Doesn’t look like there has ever been a trimmer there, no wall pocket and nail marks on the joists are from the apron being nailed directly to joists, so original carpenter must have botched it! Assuming the lack of a trimmer is behind the rotation in the joists?

Can the trimmer sit directly on the brick, or do I need padstone or to pack with slate? And assuming I’d need to wrap the end of the trimmer in dpc or felt or something if pocketing into the wall?

Not sure yet how the top of the stairs is carried, will be ripping the old carpet up over the next week or so, so will have a look then. But judging from the botch job on the short end, assuming it’ll be more of the same!

 

[Deleted member 174758]

Doesn’t look like there has ever been a trimmer there, no wall pocket and nail marks on the joists are from the apron being nailed directly to joists, so original carpenter must have botched it! Assuming the lack of a trimmer is behind the rotation in the joists?

I've seen lots of Victorian buildings and you can tell the stuff which was done by a carpenter - a carpenter would more than likely have put in a trimmer using a tusked tenon joint. In addition the work around the match boarding is incredibly scrappy - so that was never done by a carpenter and is more likely the work of jobbing builder (hence the phrase that starts "Jack of all trades, master of none"). It still happens today.

Assuming the lack of a trimmer is behind the rotation in the joists?!

Only to an extent. Joists can twist because they are overloaded, or even just poorly selected/dried. Being restrained by a joist hanger or a pocket doesn't stop them from twisting - but experience on several thousand joists on one job convinced me that it certainly helps

Can the trimmer sit directly on the brick, or do I need padstone or to pack with slate? And assuming I’d need to wrap the end of the trimmer in dpc or felt or something if pocketing into the wall?

Have you got a ledge in the brickwork which is at least 50mm wide (ideally 70mm)? If the wall is an exterior wall the trimmer joists should be treated and the ends "envelope wrapped" in something like roofing felt. Neither precaution is necessary in interior walls. You want to aim for 70mm bearing (50mm in the bare minimum). On old domestic buildings the pockets are normally straight into the brick with no padstone. If the original bricks are ropey maybe a piece of concrete paviour or a few engineering bricks laid below the bearing point would be worthwhile

Not sure yet how the top of the stairs is carried, will be ripping the old carpet up over the next week or so, so will have a look then. But judging from the botch job on the short end, assuming it’ll be more of the same!

Yes. From the photos it doesn't look like there is a trimmer in there, either

 

[tomos94]

Just a quick update in case anybody else comes across the same issue.

A structural engineer came over to provide some calcs for steel for a knock through and to assess some cracking in a brick wall. Whilst he was here I asked him about the panel wall, and as JobAndKnock suggested the match board wall can be removed and the edges of the floorboards supported by a piece of timber attached directly to the existing joist. Matchboard wall is now down and timber attached to existing joist is supporting floorboards fine, so that’s sorted.

Regarding the lack of a trimmer, the joists (around 8 by 3) actually span from the front of the house to a concrete lintel and what we see in that picture is about 1.0m of joist overhanging the lintel. The joist is approx 4.2m in length. Structural engineer said this level of cantilever is fine given joist length and thickness, so no real need for a trimmer!