I-joists.....can you mount lifting equipment??

[George Farra]

Hi All

As I buy more tools I find that I need lifting aides for either assembly, maintenance, etc. I have an 800lb capacity hand winch with brake that I use to get machinery in/out of my basement workshop. I'd like to be able to create a few mounting spots in my basement ceiling so that I can raise/lower stuff via a cable and pulley system. The floor joists above are all those I-joists. Can these things handle "hanging" weight? Should I get some 2x6 material and bolt it up to the I-joist for added strength and mount by pulleys of the 2x6?

For argument sake, I built a base cabinet for my 10" bandsaw. Its not the heaviest thing I've picked up, but would have preferred to hoist it up and lower onto the base without using my back. I have a new midi lathe that is next and that sucker weighs in over 100lbs. Needed a buddy to help me get it out of the packaging and onto a work table. Again, having a hoist set up would be very handy.

So....how do I rig this up with these I-joists??

Thank you

George

[Stew Hagerty]

As a builder, I used I-Joists and although they are actually stronger than solid wood, I always "filled in" the plywood area with extra 3/4" ply on both sides. I used these in a barn/workshop that had a basement below and automotive repair equipment above. The guy could drive cars right over the floor. Knowing what he was planning I used two sizes larger and 12"OC for the joists along with double 3/4 Plywood underlayment and I filled out the joists with that extra Ply on each side in the area where cars were going to be. I also put in a few extra posts in the basement.
Now I know that's really not a fair comparison, but I seriously think that the extra 3/4 on each side was the strongest part.

[George Farra]

Hi Stew

Thank you. I wish these are plywood core....they are OSB core. I think I'm just gonna pick up a 2x6 and bolt it to one of the joists above my work table. I will run the entire span from wall to laminated beam and hang my hoist equipment from that reinforced joist

Regards

George

[George Farra]

UGH! I just realized that I have plumbing and wiring running through everyone of these things. I guess I will need to figure out plan B

George

[Steve Baumgartner]

I think it depends on how you hang the hoist from the joist! If you can run a strap over the upper flange you are probably ok, as that is the way these assemblies were meant to carry weight. But if you hang it from the bottom flange, you run a risk of tearing that flange off the beam. The principle of an I-beam is that the top flange is in compression and the bottom one in tension while the web keeps them from sliding past each other. The web provides only a very small part of the overall strength.

[Stew Hagerty]

UGH! I just realized that I have plumbing and wiring running through everyone of these things. I guess I will need to figure out plan B

George

I can think of 3 ways to get around this.

1 - posts around the opening.
2 - cables from above to hold the opening. You may have to double up the ceiling joists or if they are also I-joists you can treat the the say we've already discussed.
And
3 - it is very typical for I-joists to use OSB. And that thought brought me to this 3rd suggestion. Another style of joists are called Open Web or Floor Trusses. Here is what you can do:
Apply something like 3/4 ply or 1X material in a pattern like this /\/\/\/
Do this on each side (I would use glue as well as a few nails or screws to hold the in place while the glue sets. This method allows you to avoid you wiring and plumbing. Oh, and I would do this to both sides but in the other direction from the first side.

[Malcolm Schweizer]

My parents' house used OSB I-Joists and that is the most wobbly floor I have ever walked on. All the hanging pulls on the dressers rattle when you walk into the bedroom, and the grandfather clock chimes rattle when you walk by it. I do not know what OC spacing they used and I don't know what they laid as a subfloor.

[William Payer]

Hi Stew

Thank you. I wish these are plywood core....they are OSB core. I think I'm just gonna pick up a 2x6 and bolt it to one of the joists above my work table. I will run the entire span from wall to laminated beam and hang my hoist equipment from that reinforced joist

Regards

George


Although most of us woodworkers tend to frown on OSB when compared to plywood, there is one area where OSB outshines plywood, and that is shear strength. OSB has about 2X more shear strength than plywood, therefore OSB constructed I-beams are stronger.

[Kent A Bathurst]

My parents' house used OSB I-Joists and that is the most wobbly floor I have ever walked on. All the hanging pulls on the dressers rattle when you walk into the bedroom, and the grandfather clock chimes rattle when you walk by it. I do not know what OC spacing they used and I don't know what they laid as a subfloor.

Plus - you don't know if the I-joists were properly sized. YOu don't mention of they are properly braced.

What I can assure you is this has nothing to do with the I-joist product per se. They are very good option. Somebody screwed up any number of things in the construction.

[Jason Roehl]

My parents' house used OSB I-Joists and that is the most wobbly floor I have ever walked on. All the hanging pulls on the dressers rattle when you walk into the bedroom, and the grandfather clock chimes rattle when you walk by it. I do not know what OC spacing they used and I don't know what they laid as a subfloor.


Plus - you don't know if the I-joists were properly sized. YOu don't mention of they are properly braced.

What I can assure you is this has nothing to do with the I-joist product per se. They are very good option. Somebody screwed up any number of things in the construction.

One of the downsides to I-joists is that they are much lighter than dimensional lumber rated for the same load. This leads to a higher tendency towards vibration. So while you may have a floor that is stiffer (less deflection) with I-joists, it may cause more rattling of objects in the room because the mass of the system is too low to absorb vibrations from someone walking across the floor.

[Kent A Bathurst]

One of the downsides to I-joists is that they are much lighter than dimensional lumber rated for the same load. This leads to a higher tendency towards vibration. So while you may have a floor that is stiffer (less deflection) with I-joists, it may cause more rattling of objects in the room because the mass of the system is too low to absorb vibrations from someone walking across the floor.

Jason - what about X-bracing btwn joists? Is that standard practice, or an "extra"?

[Stew Hagerty]

Jason - what about X-bracing btwn joists? Is that standard practice, or an "extra"?

It should be standard. I know it was in NY State.

[Jason Roehl]

Jason - what about X-bracing btwn joists? Is that standard practice, or an "extra"?

I don't know what any framing codes say about it, but I would do it no matter the floor system. I wouldn't be surprised if it were considered an "extra" based on the cheap construction I see these days. It would be a somewhat time-consuming task that no builder would throw in for free if the floor without met specs/code otherwise.

[Dan Hintz]

New house,2,000+ square foot basement, exposed I-beams... I can count the number of beams the cross-braced on one hand.

[Jim Andrew]

Building inspection dropped bridging from the I joists years ago. Back when we used solid wood joists, and bridging, it was irritating to see that plumbers and hvac guys just took a bar and knocked out the bridging.

[Steve Peterson]

As others have already said, it might not be fully code compliant, but many would do it anyway. I would try to minimize the risk by adding cross braces between 4 joists to spread out the load. Then I would try to hang the cross beam. One way would be to add 3/4" plywood shims with 1x4 or 2x4 vertical straps to your cross beam. This keeps the weight attached to the upper part of each I-beam.

Steve

[Jim Andrew]

I would not want to put all the load on one joist. The best way is to pull from the top of several. Imagine if you laid a short beam across the top of the joists, then attached to your short beam. I know it is not practical in this application, but you do not want to damage a joist. Maybe you could buy a laminated beam and put it between the joists.

[Stew Hagerty]

Bridging or cross bracing doesn't add significantly to the load capacity of joists of any kind. Their one and only function is to prevent twist.
As I stated before...

I can think of 3 ways to get around this.

1 - posts below on either side around the opening.
2 - cables from above to hold the opening. You may have to double up the ceiling joists or if they are also I-joists you can treat the the say we've already discussed.
And
3 - it is very typical for I-joists to use OSB. And that thought brought me to this 3rd suggestion. Another style of joists are called Open Web or Floor Trusses. Here is what you can do:
Apply something like 3/4 ply or 1X material in a pattern like this /\/\/\/
Do this on each side (I would use glue as well as a few nails or screws to hold the in place while the glue sets. This method allows you to avoid you wiring and plumbing. Oh, and I would do this to both sides but in the other direction from the first side.
When I brought up #3, I am not referring referring cross bracing (bridging). I am talking about in & down glued to each side of the i-joists. This allows you strengthen the joists and still get around the pipes and wiring.

[Ole Anderson]

Bridging or cross bracing doesn't add significantly to the load capacity of joists of any kind. Their one and only function is to prevent twist.
Only partly true. If you start loading a long unbraced joist, whether solid or built-up, the unbraced joist will twist and loose most of it's strength and fail due to the twist and buckling. Strength is largely based on the vertical separation of the top and bottom chords. Twisting reduces that vertical component of that dimension and promotes failure sooner than if the joist remains vertical. Braced properly the failure will be likely to be due to tension failure of the bottom chord or shear of the web.

[Kent A Bathurst]

For the record - I brought up the bracing question in reply to Malcolm's experience with the i-joists, as one possible / likely reason he had such a lousy evaluation. But - you other guys have more detailed knowledge about their effectiveness for strengthening of dead load and live load for the hoist.

[Don Jordan]

I was a framer/carpenter for several years and have some experience in this area. First of all I would laminate the floor joist using plywood on both sides. Glue and screw the plywood creating a laminated beam. You can cut around the wiring and plumbing but still laminate the joist with plywood. This is where the glue and screws will help with the load strength you need.
You can then use 2x6 perpendicular to the joist in the are you plan on lifting. You can go online and check load values on the joist and see how your floor/ceiling was engineered to know if it is built at or above code standard. You take the height of the joist x the length of the joist x the on center spacing of the joist. Some builders beef up their floors to make them nice and solid which would help in your situation.

I have a cable and pulley lift I built in my shop/garage and have attached 2x6 studs to my over-engineered roof trusses. My lift is set up to lift 440 pounds and works flawlessly for my shop equipment.
p counter much of
Cross bracing would help some but by screwing 2x6 across the bottom of several joist you will counter any twist that might occur