[PandJ]

Building small crawlspace house in California. Currently laying out I joist but am not sure how to frame the end rim joist that run parallel to I joist?

Does a mfg rim joist serve as an I joist 16" OC? There are long holddown bolts that come up from foundation for earthquake code so not possible to sister Rim and I joist together.

Thanks! Fun project, looking forward to day when asking about roof vents! lol :smile:

 

[PandJ]

let me know if need to clarify. Its the rim joist that runs parallel to the i joist. Hoping someone can call our if they know

 

[woodchopper65]

you should have stamped plans that show how its tobe framed out?

 

[jlhaslip]

The "rim board" should go all the way around the perimeter.
No sistering of joists required.

As noted above, check the prints.

 

[gregzoll]

Rim joist all around after you place the I Trusses in. Then you put on the Rims and then skirt boards for the sub-floor to attach to, after you have gone in and placed Blue XPS to help insulate those bays, before the sub-floor goes on, along with being sealed at where the sub attaches to the rim and joist.

With the Skirt and Rim, it will give you a better area to attach the plate and also secure for the Simpsons for Earthquake proofing. Your plans and the code office should have stated how things are supposed to be done.

Plenty of I-Truss sites online, with the info you need. Stark Trusses is the best resource. Just take the pdf to Kinko's and have them print it out and bind it for you. http://www.starktruss.com/wp-content/uploads/2014/02/APA-D710.pdf

 

[PandJ]

Thanks for replies. I have hundreds of I joist pdf's lain:and not one illustrates the last i joist in relation to the rim joist that runs parallel to it. Let me know if you can find one and you'll save me more torture lol! So basically....the rim joist sits on edge of sill, then there are bolts...including 18" bolts for CA hold down code. So no room for an I joist to sister up to the rim.....It can sit out about 4" off of rim but that's as close as it will get due to all the foundation bolts.

So either an I joist should go in place of rim joist ....OR the rim joist serves as structural support instead of the last i joist....? Believe me , I've scoured online and youtube for the answer or a picture of this. Hopefully this helps you understand what i'm asking.

 

[Mingledtrash]

Thanks for replies. I have hundreds of I joist pdf's lain:and not one illustrates the last i joist in relation to the rim joist that runs parallel to it. Let me know if you can find one and you'll save me more torture lol! So basically....the rim joist sits on edge of sill, then there are bolts...including 18" bolts for CA hold down code. So no room for an I joist to sister up to the rim.....It can sit out about 4" off of rim but that's as close as it will get due to all the foundation bolts.

So either an I joist should go in place of rim joist ....OR the rim joist serves as structural support instead of the last i joist....? Believe me , I've scoured online and youtube for the answer or a picture of this. Hopefully this helps you understand what i'm asking.

The reason none of your hundreds of i-joist pdf's illustrate this is because i-joists are not rated for the compression your rim board requres. Rim board actually has more compression strength than joists do, think about exterior bearing walls sitting on perimeter "joists", i joists typically have a 1/2" osb web where as rim board is usually 1 1/8" thick so you have far greater compression strength on your exterior walls. Of course, as others have stated you need to follow your engineers drawings they could call out 1 3/4 LvL as a rim board if enough compression strength is required.

 

[Msradell]

I've never seen rim boards that were not conventional lumber instead of particleboard like illustrated above! Maybe it's a regional thing but I haven't seen that done around here at all. It certainly seems like the particleboard will be much more susceptible to moisture damage.

 

[PandJ]

My spec'd rim joist are lsl, plywood engineered. Very heavy and called for 1 1/4" since small house. I'm thinking now that the word "joist" in rim joist may be the answer lol. The lsl is very heavy so I think I'm good in using. I may go ahead and use i joist at next open spot apprx 5 " oc from rim joist. Probable will block it out to rim as extra assurance.

Mingledtrash - so my question is the rim joist serving as the "end" joist. What your saying makes sense . The rim joist is structural as or more supportive in compression than the i joist based on your statement so I'm going with it. Thanks!

 

[gregzoll]

The Stark Truss pdf is about the best one that I have seen, that shows the Rim joists. I do like how they tripled at the critical point in one picture. Personally I would see that as a plus in your area, since you have to not only worry about the high winds, but also shake & quake.

 

[gregzoll]

My spec'd rim joist are lsl, plywood engineered. Very heavy and called for 1 1/4" since small house. I'm thinking now that the word "joist" in rim joist may be the answer lol. The lsl is very heavy so I think I'm good in using. I may go ahead and use i joist at next open spot apprx 5 " oc from rim joist. Probable will block it out to rim as extra assurance.

Mingledtrash - so my question is the rim joist serving as the "end" joist. What your saying makes sense . The rim joist is structural as or more supportive in compression than the i joist based on your statement so I'm going with it. Thanks!

Keep in mind that you have some wiggle room in factoring in the placement of the I Trusses. Some go 24", some stick to the 16". Because you have to place the vent stack, drain for the tub, toilet, you have to place two trusses at that point, along with how you are running the other mechanicals.

Taking the time to do your homework and getting your notes on paper, before you commit, is a whole lot easier, then having to go back and destroy a group of trusses, because someone forgot what is going to happen at that point.

As OCD as I am on some things like this. I would go along with a Grease Pencil after you lay down the Pressure Treated Sill Plate on top of the Copper or other piece you are using as a critter barrier for Termites and Carpenter ants. Go along and mark out where the rooms are with a line, make a mark where electrical and other items, so that you have to not keep pulling out the paper, or you could also put the info on a piece of paper inside a plastic bag in your hat.

You will feel those trusses and other wood products by the end of the days, if you are not compensating for your muscles burning off the same type of chemicals that we get from working out and certain drugs. You want to not overdo it either.

The place across the street from me, had two guys framing and hoisting up the walls, pulling up the roof box trusses and lifting the boards for the roof.

It probably took them about 4 months with three guys on the job, because the owner of the place wants it to last as long as the old concrete place next door. That new building is not going anywhere.

If you have not started a project thread in the project forum, start one now. Also if you are looking for ideas in certain areas, take a look at the German House rebuild.

 

[gregzoll]

I've never seen rim boards that were not conventional lumber instead of particleboard like illustrated above! Maybe it's a regional thing but I haven't seen that done around here at all. It certainly seems like the particleboard will be much more susceptible to moisture damage.

Well, we are talking about areas like Arizona, New Mexico and Vegas that are notorious for being cheap on builds. They use hardly anything in the structures, except for what is need to pass minimum code.

To me, those pressed OSB timbers may be made differently to hold up for the 10-15 years of expected lifespan of the building, before it starts to really fall apart.

 

[PandJ]

The Stark Truss pdf is about the best one that I have seen, that shows the Rim joists. I do like how they tripled at the critical point in one picture. Personally I would see that as a plus in your area, since you have to not only worry about the high winds, but also shake & quake.

gregzoll - Thanks! good info at stark truss site.

 

[gregzoll]

It was the first pdf I pulled and it was probably the best one that I have seen, that gets to the point right at the beginning.

 

[PandJ]

Here is what I am doing. I don't think need to but the ijoist blocked to rim joist should add strength. I did see on the pdf info where blocking was used on the last i joist and rim for strength. The i joist sits a bit on the sill also.

Thoughts? Big bolts are for hold downs to framing here in CA

https://www.amazon.com/clouddrive/s...Y1o2U5HKVgs?v=grid&ref_=cd_ph_share_link_copy

 

[gregzoll]

Blocking will help stabilize. If the code office did not give you any info on requirements for earthquake proofing, they should have. You can always take a trip to the local real lumber yard and find out what Simpson brackets and bolts that are needed for this.

Strengthening the whole structure, will help quiet down on the bounce noise you get when people walk around. But in turn, it can turn the whole unit into a drum and cause it to become concentrated, because it is too stiff. Also you have to keep in mind that there has to be a little give for the house to move when you get high winds or an Earthquake.

 

[PandJ]

The pic is what i did today. I'm going to repeat on the other end and also on a partition foundation wall that runs same direction. The shear walls are pretty extensive, even in a center interior wall to help limit shaking in a quake. This is a granny unit on our lot. My main house is 100 yr's old and has survived many quakes so I'm always thinking its about the nails....lol...have you seen the nails used back then:surprise:and the old growth wood too.

 

[mgp roofing]

To me, those pressed OSB timbers may be made differently to hold up for the 10-15 years of expected lifespan of the building, before it starts to really fall apart.

Wow, is that really how long your codes expect the structure of a house to last? Here, the structure, and hard to access or replace elements, must last at least 50 years.

 

[Gary in WA]

Sounds as if you are "winging" it.... good way to get in trouble. Read the engineered floor joist (not truss) plans (one with City/county, one for designer, one for builder, and another copy for framer) as said, each one is a little different per manufacturer. Your specific floor plan (layout) was designed by an engineer, or designer, don't follow another manufacturers layout, even if the same brand. Every house is different. All the rims meet APA standards, but some plans require an I-joist at the side walls (with a ply/OSB filler to break sheathing on) and some accept OSB, plywood, LVL or other for the rim. These can span a 48" opening or less, with restrictions; https://www.apawood.org/Data/Sites/1/documents/technicalresearch/paper-2004-cib-w18---rimboard.pdf

Pros would install the farthest rim on the house side- from lumber drop, lay the I-joists (check for square cut from yard) on bearings flat, then cut (joists at break) and excess length using a caulk line from each end spaced-in for the rim thickness +, stand them and nail them, then final rim. Very fast, this after adding the required hold-down solid blocking around the threaded rods. Your last joist should have been spaced 16" from the solid rim and shear floor/wall blocking ( Yours are missing-- required on the plans) added first- some require more than 16" from exterior rim.... How do you plan on insulating the rim now, or letting the Inspector compare your floor framing/supports-concrete piers, posts, connectors, etc. per plans... same reason you wouldn't add blue board to the joist bottoms before "floor" inspection (or before mechanical are run- hope for no outside wall plumbing)... bad idea. Glue the tops of joists AND glue in the groove of sheathing for better floor., ease the decking down on the glue, not let it fall - spreading glue thin. get the required end panel gap, nail the sheet while standing in the center area for full contact. Blocking may be required under any shear walls above (including interior), check the plans.

Gary

 

[Mingledtrash]

Here is what I am doing. I don't think need to but the ijoist blocked to rim joist should add strength. I did see on the pdf info where blocking was used on the last i joist and rim for strength. The i joist sits a bit on the sill also.

Thoughts? Big bolts are for hold downs to framing here in CA

https://www.amazon.com/clouddrive/s...Y1o2U5HKVgs?v=grid&ref_=cd_ph_share_link_copy

Those little blocks are not enough. your engineering should tell you how far back you must block perpendicular to the last joist and rim band. Typically you have to have blocks every 4' o.c. and it will call out 16"-2'(1 to 3 joist bays back) depending on the amount of shear transfer they want.