Anchor bolts/ plates

[sansert]

We used the 12" long J Bolts 1/2" but was wondering if anyone ever uses something other than the small washer and nut that come with the anchor. For example some sort of steel plate like this?

Simpson Strong-Tie BP-5/8-3 5/8" Bolt Dia. 3" x 3" Bearing Plate

 

[Stuart in MN]

What are you anchoring, and to what?

 

[sansert]

What are you anchoring, and to what?

LOL! Yeah I guess I did leave out some info on that. I would be anchoring 2 x 6 sill plate for my garage walls. Sorry about that. Currently have filled block wall sitting on concrete footers. Anchor bolts installed in blocks already.

 

[sierradmax]

I think it would be overkill. Unless specified by local code, washer will do. Inspector will like them..

 

[Homerr]

3"x3"x1/4" bearing plates are specified on every house we draw. WA state under 2015 IRC. AFAIK all inspectors want to see these and the bolt must be in the middle 1/3 of the p.t. plate.

Even if they aren't required in your area they are a good idea and cheap insurance at a historically weak point in buildings.

 

[RocketScott]

We have to use 3x3” galvanized washers out here. Mostly see 5/8” anchor bolts too

The old code called for 2x2” and didn’t have to be galvanized


Sent from my iPhone using Tapatalk

 

[Stuart in MN]

My garage just uses the washers and nuts that came with the anchor bolt. However, it was built 20 years ago and I don't know if there have been changes to the code requirements since then. Also, I assume local requirements will vary depending on where you live, if there are potential high wind/hurricane or seismic conditions.

 

[Zaxxn]

I used the 3" x 3" bearing plates for the same purpose. I think they were made by Simpson and fairly affordable.

--Zax

 

[Falcon67]

Can't hurt for sure. Here in the tail end of tornado alley, neither washer nor plate will keep your hut stuck to the ground in a big storm LOL.

 

[matt_i]

Can't hurt for sure. Here in the tail end of tornado alley, neither washer nor plate will keep your hut stuck to the ground in a big storm LOL.

Im curious what fails, does the steel rod break or does the washer pull-through, or do the studs simply pull out of the plywood and off the bottom plate? I always wondered what the weak link was but (thankfully) never involved in any direct storm damage.

 

[kbs2244]

The weak point is the toe nailed joint of the stud to the sill.
Look at the PICs after a wind storm went through.
The sills are in place but the building is down.

 

[Falcon67]

EF1~2, mostly external damage, stripped roof. EF3 - Roof lifts off, walls fall in on frame houses once the rafter ties (joists) can't hold them up. EF4+ Rips things off foundation, basically splinters most everything. EF5+ takes the asphalt out of the road beds, everything stripped clean to the dirt, slabs wiped clean. As above, wind pressure will just pull the stud wall right up off the plates.

 

[JoeMcGov]

EF1~2, mostly external damage, stripped roof. EF3 - Roof lifts off, walls fall in on frame houses once the rafter ties (joists) can't hold them up. EF4+ Rips things off foundation, basically splinters most everything. EF5+ takes the asphalt out of the road beds, everything stripped clean to the dirt, slabs wiped clean. As above, wind pressure will just pull the stud wall right up off the plates.

I kept reading down this thread and then...............there it was ^^^.

The "system" is only as strong as the weakest link/element. All this discussion about holding the dang sill plate down. But if you don't "reinforce" the stud to sill plate connection. And the stud to top plate connection. And the top plate to roof rafter connection. Then as Falcon67 notes the rest of the structure may fly free. But you'll be able to come back to your home and find that sparkling pressure treated 2X6 still fastened to your slab.

Put the dang washer and nut on it that came with it if you're not going to reinforce the whole "system."

Washington State requiring those massive plate washers on the bottom plate is just nuts. So glad I left that overbearing nutcase state 25 years ago.

 

[Nowater]

If the anchor bolt is just held down by a few filled concrete blocks, then that is the limiting strength factor. what is holding the bolts in place?

 

[sansert]

I kept reading down this thread and then...............there it was ^^^.

The "system" is only as strong as the weakest link/element. All this discussion about holding the dang sill plate down. But if you don't "reinforce" the stud to sill plate connection. And the stud to top plate connection. And the top plate to roof rafter connection. Then as Falcon67 notes the rest of the structure may fly free. But you'll be able to come back to your home and find that sparkling pressure treated 2X6 still fastened to your slab.

Put the dang washer and nut on it that came with it if you're not going to reinforce the whole "system."

Washington State requiring those massive plate washers on the bottom plate is just nuts. So glad I left that overbearing nutcase state 25 years ago.

Just curious as to what other ways to reinforce the rest of the building?

 

[sberry]

The sheet being nailed to the studs and plates provide the attatchment power. Its not toe nails,, and most walls built on deck and tilted up. Nailed top and bottom. If someone in code added bigger plates then there is probably a reason.

 

[strutaeng]

There's a belief that building "up to Code" is about as best as one can do. The "Code" is the minimum standard. One can always meet or exceed requirements.

I believe those 3x3 plates are only required in Seismic and high wind regions like coastal area. I don't think they are required for the rest of the country, unless the local codes require them.

Please read this article on the Garland, TX tornadoes in 2015. The publication "recommends" the plates, among other things, to better resist winds higher than the minimum wind loads, i.e., from tornadoes.

https://www.jlconline.com/how-to/framing/a-texas-tornado-lessons-learned_o

Another thing that this article reveals is the low workmanship of residential construction, but that's another issue by itself. I mean, seriously, some of those newer homes have cardboard sheathing!

OP, I would use the plates if you are in an area that has tornadoes. They are $1.40 at my local THD, so that's pocket change in the grand scheme of things.

Good Luck.

 

[RocketScott]

Part of the reason for going with a larger washer is so we can drill a larger hole in the sill plate

I drill a 1" hole to allow to allow for alignment of the sill plate, either to a chalk line on the foundation or a string line if there isn't enough foundation to snap a line on

 

[mcbane]

If the anchor bolt is just held down by a few filled concrete blocks, then that is the limiting strength factor. what is holding the bolts in place?

The foundation doesnt hold the structure down unless you have an exotic drilled pier foundation. The purpose of the bolts is to ensure that if the house and foundation are momentarily weightless due to an earthquake they stay together. The bolts also resist any lateral force that might try to slide the house off the foundation even in the absence of vertical accelerations. When all the shaking is done you want the house on top of the foundation rather than beside it.

 

[gearhead1]

There's a belief that building "up to Code" is about as best as one can do. The "Code" is the minimum standard. One can always meet or exceed requirements.

I believe those 3x3 plates are only required in Seismic and high wind regions like coastal area. I don't think they are required for the rest of the country, unless the local codes require them.

+1, I agree, code is minimum standard, I’m definitely ok making it stronger, which I did with certain areas on mine.

When I researched for mine, I seemed to remember reading somewhere in the code about those plates in a high seismic area. Mine aren’t the 3x3 but they’re bigger than the plain washer as I was ok with it better than minimum standard.

Yes some things are overkill. If it’s a cheap enough overkill cost, then I’ll do it.

 

[bad_idea]

My county required the bearing plates. I am in a 110 MPH wind zone. My inspector gave two options on attaching the roof to the sill plate (ultimate goal being to keep the roof on in high winds). Either nailing sheathing 6" around perimeter and 12" in field w/ top of sheet going to top plate or to blocking - or running all thread from j bolts through top plate with another bearing plate on top of that.

I chose the first option. The nails on the sheathing are in shear. Will take a bit to rip out all of those nails. At that point you have bigger problems. The all thread option is easily the better option but I didn't want to deal with that.

 

[Diesel Dan]

If the anchor bolt is just held down by a few filled concrete blocks, then that is the limiting strength factor. what is holding the bolts in place?

The foundation doesnt hold the structure down unless you have an exotic drilled pier foundation. The purpose of the bolts is to ensure that if the house and foundation are momentarily weightless due to an earthquake they stay together. The bolts also resist any lateral force that might try to slide the house off the foundation even in the absence of vertical accelerations. When all the shaking is done you want the house on top of the foundation rather than beside it.

While living in NW Wisconsin we experienced 100+ MPH straight winds. Neighbors garage and breezeway (insert jokes) were torn away from the 2 story house. The breezeway portion of the structure was missing the top row of cement blocks. There were sections of walls with concrete on them in the yard.

That is why I core filled my blocks and welded rebar to the j-bolts that reached the footing.

 

[bad_idea]

My concrete contractor ran the all thread for the bottom plate into the footer.