Suspending heavy objects from ceilings

[Amphibian]

I have a baby hammock that I want to attach to my ceiling. I live in an old house with exposed ceiling joists, which are also the floor joists of the floor above - if you see what I mean. The joists are not very large at all, they are only 2x4".

There are loads of guides to hanging heavy object from ceilings - such as punch bags - but these never seem to discuss the structural safety of boring holes into joists.

Likewise there are plenty of discussions about drilling through joists for piping or wiring, but these are all about lateral not vertical drilling.

What I am thinking of doing is inserting a 8mm threaded lagbolt vertically upward into the joist, to 25mm depth - I know it'll support the weight of the hammock, that is not my concern, my concern is seriously weakening the joist itself and thus causing a seriously dangerous and costly issue.

Am I right to be concerned or being daft?

 

[garyo]

Presuming it'll be a relatively temporary situation, how about threading some stainless steel wire over the beam between the cracks in the floorboards, then fix it together with mini clamps?

 

[Amphibian]

It would mean removing the plaster from between the joists - which is doable but I'd prefer to avoid doing that. If screwing into the joist is a no-no, then I'll make a tripod to suspend it, but that's not ideal. I've had a look on some hammock manufacturers websites, they all recommend a screw into a joist - seemingly without any reference to the structural integrity of the joist.

 

[joinerjohn]

How heavy, is the baby that's going in the hammock ?? Surely he/she, isn't going to be in it until an adult ?

 

[Amphibian]

He'll be a typical baby weight - I was more concerned about weight from above on a weakened joist - a joist weakened by the hole put in it - rather than by the weight of the baby.

 

[cajar]

8mm is nothing.