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How to repair rotted joist end

Joined
25 Dec 2013
Messages
221
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2
Location
Manchester
Country
United Kingdom
Hi,

I have a joist end on the ground floor which has rotted. Joist end is located in the understair closet.

Both the joist end and the wooden packer which sit inside the joist pocket have rotted. I suspect its because the kitchen on the other side of this wall has a concrete floor with a bitmuen layer. Im not sure if that kitchenfloor was orginally concrete or if it was of suspended timber construction and at some point was filled in with concrete. Hence the joist ends are exposed to a moist surface through the joist pocket.

What is the best way to repair it?

1. The joist is apporx 90mm x 70mm in diameter
2. There is sleeper wall approx 3ft from the rotted end
1. How far back do I cut it.
2. If I sister the original joist what length do the side plates need to be and approx where along the length do I bolt them
3. How many bolts do i use, what size and how far apart.
4. What type of timber do i need?

Any advice and detailed instruction would be appreciated.
 

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You can fill holes with bricks then fit joist hangers.
Other option is to replace timber then stand on slate.
Not really my area but I've had ago.

You can also resin bolt timber to wall with joist hangers on
 
Before I get too deeply into this, are there any beetle flight holes? My old eyes are not good with photos, so I have to rely on others for close scrutiny feedback.
 
Cut the rotten end off. Sister on a new piece with the end placed on some dpc etc...
 

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