Multiple / Stacked Sill Plate

[Jim Hintz]

First time I have ever run into this - house was a 2 story 2400+ built in 2008 - any ideas?

Thanks - Jim

[Rick Cantrell]

Not a problem

[Nick Ostrowski]

I see the anchor bolts for the pressure treated sill plate on the bottom but what's securing the rest of that wood sandwich to the foundation wall?

[Rick Cantrell]

"I see the anchor bolts for the pressure treated sill plate on the bottom but what's securing the rest of that wood sandwich to the foundation wall?"

Why is anything else needed?

[MARVIN TOWNSEN]

First time I have ever run into this - house was a 2 story 2400+ built in 2008 - any ideas?

Thanks - Jim
Where are you at on my island (washington state)? It should have been pony walled minimum. How are each layer secured together?? Looks like they were layering their scrap wood together to save on the burn pile:rolleyes: I guess if you built it that way you should at least use simpson ties to keep it from rolling in an earthquake. I am curious which county you are in that would allow that?? Was it inspected?? Are there any foundation ties because i dont see them? At minimum i would be concerned about crush factor, it probably doesnt matter for an inspection, but it definately could have been done better.

[Nick Ostrowski]

"I see the anchor bolts for the pressure treated sill plate on the bottom but what's securing the rest of that wood sandwich to the foundation wall?"

Why is anything else needed?

The entire premise of anchor bolts is to secure the wood framing to the foundation wall. The pressure treated sill may not go anywhere in the event of a hurricane or tornado, but what about everything else above that?

[Jim Hintz]

Where are you at on my island (washington state)? It should have been pony walled minimum. How are each layer secured together?? Looks like they were layering their scrap wood together to save on the burn pile:rolleyes: I guess if you built it that way you should at least use simpson ties to keep it from rolling in an earthquake. I am curious which county you are in that would allow that?? Was it inspected?? Are there any foundation ties because i dont see them? At minimum i would be concerned about crush factor, it probably doesnt matter for an inspection, but it definately could have been done better. House was located in Skagit County.

[Markus Keller]

Anchoring would also be my issue. The dead load will mostly keep it in place but as others have mentioned what about during high storms or hurricanes.
My guess is someone screwed up the elevations.

[MARVIN TOWNSEN]

House was located in Skagit County.
I am located in the southend near portland, and foundation ties are required as well as j bolts. I wouldnt be concerned about hurricanes, but the pacific northwest is one of the most active seismic areas in the world. I would call your local county code department, but I know that would not pass in our area:rolleyes: One major concern is w/o strapping the house could rip from the j bolts and roll off of its foundation. Hurricane straps(as we call simpson ties) are being required alot more on construction in our area:)

[Jerry Peck]

I agree with most of the posts above - what holds it down?

I suspect that they made the foundation wall too short, and that was their way of making it as high as it should have been, the question then becomes (in addition to what is holding it down): how high above grade is that pressure treated (i.e., is the siding and that stacked wood at least 8 inches above grade?

[Ron Bibler]

Agree with Jerry...Some one messed up on the foundation and a quick fix was to block it in.

Was this done to the complete foundation of just one or two section.

Best

Ron

[MARVIN TOWNSEN]

Agree with Jerry...Some one messed up on the foundation and a quick fix was to block it in.

Was this done to the complete foundation of just one or two section.

Best

Ron
This is a common type of construction (foundation)in our area. It is generally used on sloped ground. As long all the wood part of the structure is properly above grade it is fine to do, as long as it is properly constructed, this is not. normally a pony or stub wall is built to make up the difference, but it must be properly constructed and secured and kept above grade. Alot of contractors in our area do this to save on foundation costs. I would like to see the inspection from the county inspector.I have been around construction my whole life and that is some of the worst work i have seen on a " properly inspected home:confused: " anyway just my 2 cents

[Jim Hintz]

Thanks to all that responded. The stacked sill went around the entire foundation footprint. I read somewhere on the web last night that nailing the multiple layers of plate together was allowed in the Everett area, but that's 30 miles south and in a different county. I imagine this configuration was intentional which saved the builder 2-3 cu.yds of concrete per residence, times 200 homes - $40-$60K over the entire project. I'll recommend the installation of additional ties / strapping to the client. Thanks Again for all of your comments.

Jim Hintz

[MARVIN TOWNSEN]

Thanks to all that responded. The stacked sill went around the entire foundation footprint. I read somewhere on the web last night that nailing the multiple layers of plate together was allowed in the Everett area, but that's 30 miles south and in a different county. I imagine this configuration was intentional which saved the builder 2-3 cu.yds of concrete per residence, times 200 homes - $40-$60K over the entire project. I'll recommend the installation of additional ties / strapping to the client. Thanks Again for all of your comments.

Jim Hintz
I have never seen stacked sill plates or pony walls which go all the way around the home. Even with strapping I would be afraid to own that house, considering the increased seismic activity in the pacific northwest. I am still curious to find out the code in your area for foundation ties.

[Mark S. Connely]

This is acceptable as long as the first layer is treated lumber and bolted and the exterior is properly sided, this is a cheap way to raise the foundation to have a taller basement :D

[Fred Weck]

There is nothing wrong with it, it has been done according to code:

Foundation cripple walls shall be framed of studs not smaller than the studding above. When exceeding 4 feet (1219 mm) in height, such walls shall be framed of studs having the size required for an additional story. Cripple walls with a stud height less than 14 inches (356 mm) shall be sheathed on at least one side with a wood structural panel that is fastened to both the top and bottom plates in accordance with Table R602.3(1), or the cripple walls shall be constructed of solid blocking. Cripple walls shall be supported on continuous foundations.

As far as seismic goes, it has the right washers.
Nailing the plates together would need to follow Table R602.3 (1), which would be 1-10d nail every 24" o.c.

[MARVIN TOWNSEN]

There is nothing wrong with it, it has been done according to code:

Foundation cripple walls shall be framed of studs not smaller than the studding above. When exceeding 4 feet (1219 mm) in height, such walls shall be framed of studs having the size required for an additional story. Cripple walls with a stud height less than 14 inches (356 mm) shall be sheathed on at least one side with a wood structural panel that is fastened to both the top and bottom plates in accordance with Table R602.3(1), or the cripple walls shall be constructed of solid blocking. Cripple walls shall be supported on continuous foundations.

As far as seismic goes, it has the right washers.
Nailing the plates together would need to follow Table R602.3 (1), which would be 1-10d nail every 24" o.c. I would guarantee that would not pass code in my area. there area no foundation ties and we have alot more seismic activitiy in the pnw and mn has.

[Wiley Lavigne]

My best guess is that they didn’t have a clue how to deal with the nuts and bolts extending above the sill plate. I can see the light coming on while they pondered this dilemma ---- “We can shim the plate with 2x material to get above the nuts and bolts then add the second sill plate over the top. Yep that’ll work” :D any bets Wiley

[Fred Weck]

I would guarantee that would not pass code in my area. there area no foundation ties and we have alot more seismic activitiy in the pnw and mn has.

There is nothing in the IRC that requires foundation ties in lieu of anchor bolts, including the Washington State amendments https://fortress.wa.gov/ga/apps/sbcc/Page.aspx?nid=14 :

R403.1.6 Foundation anchorage. When braced wall panels are supported directly on continuous foundations, the wall wood sill plate or cold-formed steel bottom track shall be anchored to the foundation in accordance with this section. The wood sole plate at exterior walls on monolithic slabs and wood sill plate shall be anchored to the foundation with anchor bolts spaced a maximum of 6 feet (1829 mm) on center. There shall be a minimum of two bolts per plate section with one bolt located not more than 12 inches (305 mm) or less than seven bolt diameters from each end of the plate section. In Seismic Design Categories D0, D1 andD2, anchor bolts shall be spaced at 6 feet (1829 mm) on center and located within 12 inches (305 mm) of the ends of each plate section at interior braced wall lines when required by Section R602.10.9 to be supported on a continuous foundation. Bolts shall be at least 1/2 inch (13 mm) in diameter and shall extend a minimum of 7 inches (178 mm) into masonry or concrete. Interior bearing wall sole plates on monolithic slab foundation shall be positively anchored with approved fasteners. A nut and washer shall be tightened on each bolt of the plate. Sills and sole plates shall be protected against decay and termites where required by Sections R319 and R320. Cold-formed steel framing systems shall be fastened to the wood sill plates or anchored directly to the foundation as required in Section R505.3.1 or R603.1.1.
R403.1.6.1 Foundation anchorage in Seismic Design Categories C, D0, D1 and D2. In addition to the requirements of Section R403.1.6, the following requirements shall apply to wood light-frame structures in Seismic Design Categories D0, D1 and D2 and wood light-frame townhouses in Seismic Design Category C.
1. Plate washers conforming to Section R602.11.1 shall be provided for all anchor bolts over the full length of required braced wall lines. Properly sized cut washers shall be permitted for anchor bolts in wall lines not containing braced wall panels.
2. Interior braced wall plates shall have anchor bolts spaced at not more than 6 feet (1829 mm) on center and located within 12 inches (305 mm) of the ends of each plate section when supported on a continuous foundation.
3. Interior bearing wall sole plates shall have anchor bolts spaced at not more than 6 feet (1829 mm) on center and located within 12 inches (305 mm) of the ends of each plate section when supported on a continuous foundation.
4. The maximum anchor bolt spacing shall be 4 feet (1219 mm)for buildings over two stories in height.
5. Stepped cripple walls shall conform to Section R602.11.3.
6. Where continuous wood foundations in accordance with Section R404.2 are used, the force transfer shall have a capacity equal to or greater than the connections required by Section R602.11.1 or the braced wall panel shall be connected to the wood foundations in accordance with the braced wall panel-to-floor fastening requirements of Table R602.3(1).


Foundation ties are an alternate to anchor bolts if they are approved by the building official, or as an engineered design.

(Edit: Sorry about the bold, something happened with copy and paste)

[MARVIN TOWNSEN]

[quote=Fred Weck;169004]There is nothing in the IRC that requires foundation ties in lieu of anchor bolts, including the Washington State amendments https://fortress.wa.gov/ga/apps/sbcc/Page.aspx?nid=14 :
I seem to stand corrected thank you. But i will say i have been out of the construction industry for awhile. On the other hand i do know for a fact that as of a few years ago our local county was requiring foundation ties as well as j bolts, but we also are only 40 miles from Mt Sthelens. So it may have been a county required item only. I am curious how this would stand up in ca.
Living so close to the mt. i get tremors at my house from time to time, so i am a little overboard( paranoid) on structural items. My neighbors(county inspected )pole barn went down a couple of years partially due to tremors. anyway thanks for the link and i am learning quite a bit of info on this site.

[Rick Cantrell]

I stand by my "Not a problem" until someone shows my different.

[Steve Frederickson]

I stand by my "Not a problem" until someone shows my different.


Here's a good primer on the topic, in case anyone's interested (good weekend reading) ;)

http://www.google.com/url?sa=t&source=web&cd=2&ved=0CCEQFjAB&url=http%3A%2F%2Fwww.fema.gov%2Flibrary%2Ffile%3Ft ype%3DpublishedFile%26file%3Dfema232part1.pdf%26fi leid%3D4444c2b0-74f8-11db-9b42-000bdba87d5b&rct=j&q=Homebuilders%E2%80%99%20Guide%20to%20Earthquake-Resistant%20Design%20and%20Construction&ei=cSTgTZ7PA8rB0AHRm52oCg&usg=AFQjCNGzLi8SPWynGGnp013DdHnD5vQhFQ

[Rick Cantrell]

Here's a good primer on the topic, in case anyone's interested (good weekend reading) ;)

I read it, did not see anything, perhaps you could show me.:D

[vincent jennings]

Careful here.
There are minimums for pony walls, below which, walls must be solid.
Just think about a 3" or 4" stud with 2 16d nails into both ends.
My money says, it splits.

[MARVIN TOWNSEN]

Here's a good primer on the topic, in case anyone's interested (good weekend reading) ;)

I read it, did not see anything, perhaps you could show me.:D

Interesting, i am in a d2 area, I am now curious if maybe the inspectors may have mis-interpreted the codes. It was when they first changed the codes when the problems occured. Stil i would put ties in they arent that expensive. Why not over build, they keep upgrading the codes and seismic in our area is ever increasing. Before st helens popped its top, no one ever even talked about earthquakes in washington. I am going to call the county on tues and double check the codes for my area out of curiosity.

[Rodger McBride]

First time I have ever run into this - house was a 2 story 2400+ built in 2008 - any ideas?

Thanks - Jim
What I see in your pictures amount to nothing more than wood "Shims". Proper length studs should be used. Not a shim supported wall even if it is anchored. Here all shims must be metal per code,but that
would still fail inspection. This wouldnt even be considered stacked plates.

[H.G. Watson, Sr.]

Sorry so late to the party Jim Hintz, got your PM this morning, but was interrupted early in the day and never had a chance to chime in until now.I agree completely regarding the problems expressed by another poster regarding rolling.There has been absolutely NO lapping in any of the corner joints, inside or outside, this is a tremendous problem, as are the four up blocks.Compression is not the main concern sheer rolling over and/or folding is.Anything built-up in the field excess 3 members milled lumber - requires engineering. No way this was executed per stamped plans. The orientation is wrong regarding solid. Solid upright and lapped with strapping perhaps, not four layers of 2x on side.Tearout at first two lower "layers" above sill was hacked - looks like someone went nuts with a reciprocating saw, curious if the treated sill is similarly hacked.Wonder if this "modification" was a "repair" post rough inspection after site left exposed or damaged mid-construction. Perhaps there were other issues even later on.I'd call this out for sure. Not even the basics regarding the most simpliest tie in lapping layers, let alone lapped members/joints. Not even the simpliest banding or strapping and nothing present to prevent folding or rolliing in.Even a simple double sole or top plate is lapped - your instincts are correct - this is wrong; especially in your seismic region.Curious what's on the outside - stucco, EIFS, veneer masonry? Don't see a membrane or thermal break metal to prevent moisture transmission between PT sill and the "stacked" untreated, or between foundation and sill, and nothing to indicate a termite shield either.

[Ian Page]

If this was 'intentional' as reported by Jim Hintz - to save the contractor some big bucks (per each x 200), then IMO he should not be in the housing construction business. One can only hope the poured height of this foundation wall was an anomaly and he quickly learned by his mistake. As others have indicated, clearly problematic with regard to potential seismic activity. I doubt any AHJ in CA would have written this off as is and certainly not without additional strapping from sill to plate.

[MARVIN TOWNSEN]

Careful here.
There are minimums for pony walls, below which, walls must be solid.
Just think about a 3" or 4" stud with 2 16d nails into both ends.
My money says, it splits.
Your money says it splits my experience say the dont if done correctly:Dp.s my local codes say you need 3 16d nails per board on each end per 2x6.

[H.G. Watson, Sr.]

This is apparently an irregular structure, suggested by the middle photo.

That same photo also shows the errors in the plate, note bolt to the right and proximity to cut end. We cannot see the floor joists or girders in this photo (concerning - where are the doubles at this irregularity)?

Looks like it was designed for 3"x sill minimally - designed being the key word - and the plans should indicate; and there is no doubt that the builder has double-trouble 'screwed the pooch' when it came to placement of the reinforcments for 6" sills at the reenterant (inside or interior) corner(s?) and failed to use 3"x sills, then hired a 'hack on crack'? without a drill or a proper saw and not even rudimentary wood orientation, selection, or carpentry knowledge or skills to lap what I am guessing was to have been a double plate.

We have no description of the structure, we can see joists (i-joists? Trusses?) bearing upon this abortion. Common seams all the way up - including one bearing over same and 1" off from sheathing seam.

You cannot use prescriptives beyond the limitations - so no point in blindly throwing IRC citations where they do not apply, especially in an area with multitude of geological/geotechnical critical concerns seismic, volcanic, etc., soft soils, slides, expansive soils, water, etc.; when you have no idea what the structure characteristics are nor if D2+flood+snowloads or whatever.

You may not build a shed like this you certainly can't build a house this way, esp. in a D1/2 zone in PNW.

I don't recall the OP having suggested the stem wall height was anything short of the maximum allowable for SDS D. regardless of the mapped USGS seismic - there is still the possiblity that soil/conditions upgrade the SDS further.

Every picture concern - slippage; also shrinkage. For an area with precipation - roof drainage/pooling also.

[MARVIN TOWNSEN]

AMEN, AND IF ITS UP TO CODE, THEN THEY NEED TO BE CHANGED. Any way I think when it all comes down to it, the work is shoddy, all codes are different in various states and counties around the U.S.A., BUT no matter what the codes or seismic conditions this is shi$$y work. Now as an inspector what is he supposed to do about it??? My father built better structures on our back 40,our cows were safer, and that was over 40 years ago and there were "no" volcanoes in the pnw back then!!!!

[TR Platt]

Two issues I would have with that installation.

First, what wind zone are you in, and do you need an uplift connection?

Second, you have no visible sliding connection. Sliding is applicable to wind pushing a house off the foundation, but it is also applicable to the soil pushing the foundation *in*.

Typically the joists nailed to a single sill plate, and the plate bolted, will give you the sliding connection.

Now, there are ways to provide both uplift and sliding connections to correct the issue. Sliding could be corrected with a lot of nails connecting the plates together; uplift by tension ties applied to the outside.

Again, wind may not be a concern, but soil pressure probably is. Expansive soils such as clay will be a significant problem.

edit: seismic would also be an issue for sliding.. sorry, I don't deal with seismic :)

[Kristi Silber]

I envision homeowners deciding after the foundation is poured that they wanted a finished basement with a high ceiling. Contractor says, You got the money? We'll make it happen.

I don't think it's a bad solution to the problem, it just wasn't done well. As HG Watson said, the lack of staggered joints and moisture barrier are basic mistakes.

I agree with someone earlier that having a pony wall here would be a bigger problem than stacking. Not only is there high potential for splitting such short pieces, with seismic or storm activity there's potential for torsional movement to cause complete collapse of the wall.

"A special case of a weak storey is the collapsing knee wall, also called "cripple wall" or "pony wall." The knee wall is the short stub wall in some buildings between the top of the concrete or masonry foundation and the ground floor joists. Its collapse threatens the integrity of the entire structure. The deficiency is often a lack of bracing rather than large openings in the knee wall."
(From an article called "Ensuring Good Seismic Performance with Platform-Frame Housing, Ensuring good seismic performance with platform-frame wood housing - IRC - NRC-CNRC (http://www.nrc-cnrc.gc.ca/eng/ibp/irc/ctus/ctus-n45.html). It also points out that the primary weakness of many houses is often in walls that have a lot of openings for windows and doors.)

The plywood sheathing strengthens and ties the wall together on the outside, where it's needed most. One book I have says that multiple sill plates are preferrable to one in earthquake- and tornado-prone areas because they afford more nailing area for the sheathing. The girders and joists will also help keep things in place. It looks to me like the layers were glued (hopefully the long pieces were nailed, too).

What I don't get is, where are the joists? What's the "story" behind and above all that insulation?

(Huh - now that I think about it, how would you have a continuous, fully usable double sill with such large washers in the way without at least one layer of blocking? With a lot of narrow (short horizontally) walls and corners, they could easily get in the way of the floor joist spacing. Is there even room for a rim joist? Maybe part of the problem was the foundation contractor not putting the anchors in the right place, although it looks like they might be far enough from the ends if one goes by a minimum of 7X the bolt diameter.)

As long as the layers are well attached to each other, I doubt this is going to be the weak spot in the event of seismic activity, even with the poor workmanship. It may even help having so many layers to absorb some of the distortion in the event of a cracked foundation.

My two cents!

PS The google link didn't work for me, but the whole FEMA book is available here:
FEMA Library - Homebuilders' Guide to Earthquake-Resistant Design and Construction (http://www.fema.gov/library/viewRecord.do?id=2103)