Packing up a joist, adding noggings and sistering

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Morning All,

Struggling to find any answers to the following questions, and hoping someone out there has them.

Situation: replacing rotten 110mm joist (end of the room) and part of the wooden sole plate it rests on (cutting back to where not rotten). Closest matching joist I can find is 100mm.

How do I make up the 10mm gap to make the new joist level with rest of the floor? make the replacement section of sole plate 10mm thicker than the rest therefore raising the joist 10mm? keep the sole plate the same and pack the joist 10mm up - if so, what is the accepted method for packing up a joist - 10mm wood shims on each of the sleeper wall contact points made from offcuts of joist?

Other question is if you're adding noggings or sistering with a marginally smaller joist (100mm vs. 110mm), where do you join the new joist? flush with top, flush with bottom, in middle with 5mm top and bottom gap?

Thanks in advance for any help
 
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JP_

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buy some 5mm ply (or 10mm) and shove it under

Sistering, flush with top. Or is this upstairs floor? I've only had to deal with ground floors so no problem if bottom is higher.
 
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Thanks - ply makes sense now I think of it.

It's ground floor - if I sister to top should I also stick some ply under there to bridge the gap to bottom?

Noggings - does it matter where you place them (flush top, bottom or middle)? for the noggings what is the right joining method? is it sheradised twist nails in end grain or in at an angle from the inside? Also what length of fixing is generally required?
 

SFK

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replacing rotten 110mm joist (end of the room) and part of the wooden sole plate it rests on
I tend to put a layer of 'damp proof course' under new wood when replacing rotten joist ends.
https://www.toolstation.com/damp-proof-course/

Noggings - does it matter where you place them (flush top, bottom or middle)
These Noggins are to stop joists rotating.
So it should go from top to bottom of joist.

I would use the offcuts from the new joist that you are fitting (in your case 100mm).

As they should be in snugly, fixing method is not that important (I use screws).
They do not need to be in a perfect line. I off-set them so I can screw though joist into ends of noggins.

If needed, Putting Noggins accross whole length of floor (in middle of floor), and having the screwed in place, dramatically reduces floor bounce and vibration.

https://twitter.com/hawkland_ec/status/1001754782669901824

SFK
 
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ok, thanks. Should I put noggins in at the ends, essentially creating like a closed frame, or is that overkill?

I also need to install a couple of new air bricks - should I be worried about removing bricks from the wall or is 1 (2 max - 1 whole and 2 halves) nothing to worry about in terms of the supporting wall structure?
 
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SFK

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I put enough nogins in so that when I stood on joist at joint it did not move too much (technical I know).
But if you are worried, put in too many as nothing lost
But I kept nogins away from wall (say 1 foot) as did not want condenstaion from wall on side of noggin.

couple of new air bricks - should I be worried about removing bricks from the wall
Sould not matter - walls are designed to cope with that
But in my old house the lime mortar is poor so the bricks above also came loose, and then the ones above that . Have to be carefull that you do not fix layer above and tehn need to fix layer above and then take down whole wall.

Drill out mortar arround brick, use a Chisel or SDS Chisel drill to carefilly remove small sections of brick.

Travis perkins sell stone air bricks (if you do not want to use plastic).
They also sell stone 'cavity liners' which you can use on the inside leaf of the wall (not seen these anywhere else).
https://www.travisperkins.co.uk/pro...s-and-blocks/brickwork-ventilation/c/1500038/

And don't forget that if you put air bricks at front of house you need a throughput of air. So you need air bricks on othersie (or side) of room for air to escape to.

SFK
 
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Take it you are not using hangers?

Don’t put noggins too near the wall, say 150mm from wall. Others where you need them.

knock out your air vent brick, knock a full brick out from outside, As it’s neater, then whatever you need To butcher on the inside, as you won’t see it.

I have vents on all outside walls and interior so it’s all connected.
 
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No hangers, joists sitting on sleeper walls at each end and in middle, assume hangers for the noggings wouldn't be necessary?

Will be fun and games trying to get the correct brick on the inside once I've knocked out the outside one! Assume if I can fit a drill in from the outside I should pilot a hole so I know what brick to take out on the inside?

Thanks for the link to the stone air bricks btw, prefer those to the plastic ones
 

SFK

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fit a drill in from the outside I should pilot a hole so I know what brick to take out on the inside
SDS Drill and a long SDS drill bit.
Drill from outside though motar and then right though wall all round outside brick (stich drilling)


I have This (and also 12mm).
https://www.screwfix.com/p/dewalt-10-460mm-extreme-2-sds-plus-masonry-bit/23524

And this
https://www.screwfix.com/p/mac-allister-msrh600-2-6kg-electric-sds-plus-drill-220-240v/994fy
Also great for getting plaster off wall and breaking up concrete.
This is a cheap light weight one.
You might want to spend a bit more to get more impact energy.
https://www.screwfix.com/c/tools/sds-drills/cat830818#category=cat830818&sort_by=price
 
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Thanks, SDS has been on my list to get for a while, have numerous jobs building up that I need one for. Thanks for all the info!
 
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