Whilst screwing down floorboards now that the plumbers and electricians have finished, I've noticed that there are a few joists in our property which, in the past, have been heavily notched.
In a couple of places the notching goes down half the height of the joists, and possibly about 10in in length (I'm pretty rubbish at estimating lengths though, and didn't think to measure until writing this post up). A couple look like the were done a very long time ago, and were possibly for old wastes from toilets, or something. Another is more recent, and was under where a shower cubicle was fitted in a bedroom, to allow for its waste pipes.
The worst one does have a bit of 2"x4" timber sistered to the side of it, but this doesn't extend much beyond the length of the hole, is notched itself (though to a much smaller extent) and isn't fixed on with particularly sturdy looking screws.
All joists are 10"x2" (I think, definitely 10", and I think the width was 2" - I did measure these, but can't remember 100%) and are spaced about 1' apart.
So, my question is, what is a good way to strengthen/reinforce these joists?
I'd assume that the ideal way would be to sister the joists with new 10"x2" timbers along their whole length; however, this would be a real hassle, as it would mean removing all the new plumbing and wiring that also passes through the joists.
Next best, I assume, would be to sandwich the damaged areas with the timber, extended as much on either side as possible, and bolted together. This would be slightly easier, however, in some places new wiring/plumbing runs pretty close to the notches (usually through existing drilled holes or notches), so timbers would have to be quite short, quite narrow, or would also need notching to fit around pipes or wiring.
Would another option be to use steel strapping across the notches (the kind with pre-drilled holes - something like this)? This would be able to extend much further, as it would be easier to fit between wires and pipes, and I could probably get 2 or three either side of a joist. Would it actually add the necessary reinforcement though?
In a couple of places the notching goes down half the height of the joists, and possibly about 10in in length (I'm pretty rubbish at estimating lengths though, and didn't think to measure until writing this post up). A couple look like the were done a very long time ago, and were possibly for old wastes from toilets, or something. Another is more recent, and was under where a shower cubicle was fitted in a bedroom, to allow for its waste pipes.
The worst one does have a bit of 2"x4" timber sistered to the side of it, but this doesn't extend much beyond the length of the hole, is notched itself (though to a much smaller extent) and isn't fixed on with particularly sturdy looking screws.
All joists are 10"x2" (I think, definitely 10", and I think the width was 2" - I did measure these, but can't remember 100%) and are spaced about 1' apart.
So, my question is, what is a good way to strengthen/reinforce these joists?
I'd assume that the ideal way would be to sister the joists with new 10"x2" timbers along their whole length; however, this would be a real hassle, as it would mean removing all the new plumbing and wiring that also passes through the joists.
Next best, I assume, would be to sandwich the damaged areas with the timber, extended as much on either side as possible, and bolted together. This would be slightly easier, however, in some places new wiring/plumbing runs pretty close to the notches (usually through existing drilled holes or notches), so timbers would have to be quite short, quite narrow, or would also need notching to fit around pipes or wiring.
Would another option be to use steel strapping across the notches (the kind with pre-drilled holes - something like this)? This would be able to extend much further, as it would be easier to fit between wires and pipes, and I could probably get 2 or three either side of a joist. Would it actually add the necessary reinforcement though?
