Hanging heavy bag from Garage roof

[withers]

Hi thought I would post this here for some advice about the best way of going about hanging my new aqua punch bag from my garage roof.

Ill try and give as many details as I can with photos to give you a clear view of what my idea is, hopefully my idea will take away impact and transfer away from the foundation whilst providing a secure way to hang the bag, let me know what you think.

Couple of notes:

• Fixing the bag to the wall is not an option
• I want to avoid a free standing heavy bag bracket as i want to be able to move around the bag
• Hanging it outside is not an option

The aqua bag is an A3 buoy filled with water and weighs around 40kg see the below image, they are solid and you can hit them as hard as you want they will never split/break.

I assume the pieces of wood holding the garage roof up are 'rafters' please correct me if I'm wrong see the below image:

I am not sure which wood the rafters are made of, I have provided a close-up picture below and some measurements:

Width of rafter is 1.5 inches thick
Height of rafter is 3 inches

There are multiple rafters that span the garage and they are all approx 22 inches apart, see below:

I know attaching the bag in any way directly to any of the rafters is very likely a bad idea and eventually, the rafter would likely break either due to a rope or chain wearing the rafter away through friction or the constant impact of the bag being hit.

My idea is below please let me know if this is a good idea or not.

I have plenty of wood from broken down pallets along with a D shackle and a 200mm 3/8 eye bolt with washer and nut.

What I intend to do is bond the wood together as one single peice of wood or buy singular pieces and then fix the wood to the rafters either on the top or bottom as (pictured below) (ill probably go a few pieces thick) to add extra strength, open to suggestions on this:

Then drill a hole through the centre of the wood (not the rafter) and fix the eye bolt through the centre of the piece of wood and then put the washer and nut on the top of eye bolt and tighten it up

Then place a D shackle through the eye bolt loop and hang the aqua bag via a piece of strong climbing rope from the D shackle, this will allow me to easily take the bag down by unscrewing the Dshackle from the eye loop

Having it dangle from a rope will make the aqua bag spin taking some of the impacts away from the foundation.

 

[withers]

bump

 

[Bouy]

Bump after 5 minutes? If thats urgent yes its a brilliant proposal do as you suggest - or wait for some more considered responses

 

[withers]

Bump after 5 minutes? If thats urgent yes its a brilliant proposal do as you suggest - or wait for some more considered responses

Ah, apologies for the early bump.

Is there anything you would add or do differently?

 

[Bouy]

I would change the orientation of the wood you place across the rafters so they are vertical and screw/glue together. Place a spreader plate piece of wood on top of this before you put the I bolt through to dissipate the point load. This sort of question has been asked before, do a search on punchbag

 

[Deleted member 174758]

Looks like a Fink truss roof structure to me. Those lightweight truss frames are designed to hold the roof up and carry a skin of plasterboard but are hardly the strongest timber frames and I somehow doubt hanging 40kg off the middle of the rafters (plus the additional forces from hitting it) is going to do it much good.

 

[withers]

Looks like a Fink truss roof structure to me. Those lightweight truss frames are designed to hold the roof up and carry a skin of plasterboard but are hardly the strongest timber frames and I somehow doubt hanging 40kg off the middle of the rafters (plus the additional forces from hitting it) is going to do it much good.

Do you reckon getting some extra timber frames to span across the garage and fixing them together would add a significant amount of strength?

 

[withers]

I have made the first proto type of it, got some rubber blocks on the way and I will be adding a 3rd piece of wood. The block of rubber should act as a shock absorber and take some of the impact.

So the way it will work is eye bolt goes through rubber block first and 3 planks of pallet wood which sits across the rafters.

I am also considering fixing two blocks of wood to the rafters and securing them to the rafters then sitting the planks on the top of the wood.

 

[Deleted member 174758]

Thecthing about Fink trusses is that they are engineered to be as light as possible, which is why the manufacturers always refuse to guarantee them if they are subjected to point loads or excessive dynamic loading.

When you unload these off the delivery lorry they are generally light enough for two guys to handle them, but you do have to handle them with care to avoid breaking them, because they are relatively fragile until fully installed. Frsnkly, I'm always amazed that they can carry the weight of tiles, etc that gets loaded onto them. Somewhere on yours there will be a manufacturer name and date - I suggest you might want to see if the manufacture has published any loading data or can give you better advice

Whatever else in your case I think it would be preferable to buy a couple of joists, say 5 x 2 or 6 x 2 C16 structural grade softwood, bolt them together and install them side to side between the bottom chords of the roof with the ends resting on top of the wall plates (100mm bearing - the joist ends can be tapered to get them in) that seem to be visible in your photos - then bracket and screw them in place to stop any movement. That will directly transfer losd into the walls, not the roof. Call me risk averse, if you like

 

[withers]

Thecthing about Fink trusses is that they are engineered to be as light as possible, which is why the manufacturers always refuse to guarantee them if they are subjected to point loads or excessive dynamic loading.

When you unload these off the delivery lorry they are generally light enough for two guys to handle them, but you do have to handle them with care to avoid breaking them, because they are relatively fragile until fully installed. Frsnkly, I'm always amazed that they can carry the weight of tiles, etc that gets loaded onto them. Somewhere on yours there will be a manufacturer name and date - I suggest you might want to see if the manufacture has published any loading data or can give you better advice

Whatever else in your case I think it would be preferable to buy a couple of joists, say 5 x 2 or 6 x 2 C16 structural grade softwood, bolt them together and install them side to side between the bottom chords of the roof with the ends resting on top of the wall plates (100mm bearing - the joist ends can be tapered to get them in) that seem to be visible in your photos - then bracket and screw them in place to stop any movement. That will directly transfer losd into the walls, not the roof. Call me risk averse, if you like

Thanks, I have tried my best to understand your suggestion and this is my understanding of it (please let me know if right or wrong)

In the picture below where the red squares are is where I would place the joists bolted together side by side so they are 'wedged' between the rafters and above the metal plate on the wall just above the window which I assume is the "wall plate" that you refer to, the joists of course resting against the wall.

Therefore when someone hits the punch bag or the punch bag moves the impact/load that travels down the rafter is transferred into the joist and into the walls and not into the rest of the roof as well as also giving the rafters some extra strength as the wood pushes out against the rafter?

 

[Dereekoo]

Thecthing about Fink trusses is that they are engineered to be as light as possible, which is why the manufacturers always refuse to guarantee them if they are subjected to point loads or excessive dynamic loading.

When you unload these off the delivery lorry they are generally light enough for two guys to handle them, but you do have to handle them with care to avoid breaking them, because they are relatively fragile until fully installed. Frsnkly, I'm always amazed that they can carry the weight of tiles, etc that gets loaded onto them. Somewhere on yours there will be a manufacturer name and date - I suggest you might want to see if the manufacture has published any loading data or can give you better advice

Whatever else in your case I think it would be preferable to buy a couple of joists, say 5 x 2 or 6 x 2 C16 structural grade softwood, bolt them together and install them side to side between the bottom chords of the roof with the ends resting on top of the wall plates (100mm bearing - the joist ends can be tapered to get them in) that seem to be visible in your photos - then bracket and screw them in place to stop any movement. That will directly transfer losd into the walls, not the roof. Call me risk averse, if you like

Be doubly amazed then because they are also designed to take a snow load of 60kg/m² which is similar to tile loads

 

[JP_]

Just get a big joist or two to span the gap, if not room to manoeuvre one in and onto the wall plates, then joist hangers?

 

[withers]

Just get a big joist or two to span the gap, if not room to manoeuvre one in and onto the wall plates, then joist hangers?

I don't quite understand you. Are you saying get some very long joists in to go across the rafters from left side of the garage to the right and fix them down then fix the bracket to the top of the joists? and if not feasible use smaller pieces and joist hangers?

 

[Deleted member 174758]

Surely the joist hangers would go onto the wall plates in the event that there isn't sufficient space to get them in atop the wall plates

 

[withers]

Surely the joist hangers would go onto the wall plates in the event that there isn't sufficient space to get them in atop the wall plates

I reckon they would yes.