Has anyone ever seen a stemwall framed liked this?

Or like this?



These two methods seem to be fairly popular in Oregon, I've never seen a floor/stemwall constructed this way any where else.

The argument for this construction method is the sheathing height is decreased because the rim board is eliminated.  However, in my mind the cons outweigh the pros:

1.)  There is a thermal bridge through the stemwall at the corner where the floor meets the wall.
2.)  Stemwall construction would become more complicated and time consuming.
3.)  Proximity of the I-Joist to the concrete could be problematic, requiring additional measures and more time and effort.
4.)  The crawspace height is reduced making it harder for other subs to install and work in and moisture from the ground is more likely to be an issue.
5.)  Nut and Washer of anchor bolts protrudes into floor sheathing and bottom wall plate, requiring additional notching.
6.)  If you want to run plumbing or electrical down through the wall bottom plate and into the floor, this is nearly impossible with this configuration.

QuoteI've never seen a floor/stemwall constructed this way any where else.

It looks more like an old commercial masonry building where the joists have fire cut ends embedded in brick pockets. I don't see an advantage for residential foundations.

I'm trying to determine if its easier to write a module that draws the anchor bolts or just bring in the component (pre-drawn).  I've never brought in a component before so something I need to explore further.  The other thing I feel is key is to make sure any of these minor components are modeled in such as way as to remain fairly lightweight within the model.  No one is going to want to use a feature that bogs down their overall model.  That is my one big gripe with using the 3D Warehouse models, the polygon count on most models is usually outrageous.

The 1/2" and 5/8" anchor bolts, washers and some standard nuts.



View models here:

https://3dwarehouse.sketchup.com/model/8d99457a-d1a4-488f-bea7-eeddfe8a8b67/Anchor-Bolts

Version 1.0.7 - 03.19.2017
- Added 1/2" and 5/8" Dia. Anchor Bolt option to stemwall and slab on grade foundations.
- Anchor bolt lengths are nominal 10", 12" and 14", square washers are 2"x2" or 3"x3".



View model here:

https://3dwarehouse.sketchup.com/model/d167e6ba-96b1-4211-96df-34b8371d7d5e/Anchor-Bolts-in-Stemwall-Foundation

The anchor bolt, washer and nut are three separate files that are loaded in as components.  Then the nut and washer components are inserted inside the bolt component and exploded so only the solid group(s) remain.  Its pretty amazing what you can do with a robust API and a little bit of Ruby code.

It took me most of today to figure out how to do all of this since I'm in uncharted territory but now that I've got it kind of figured out it opens up the possibility for a host of other things (holdowns, windows, doors, vents etc...) for this plugin and the others I'm working on.

The cosmetic threads actually render quite nicely as does my rebar material/texture.  I just realized I have not added any custom materials into the foundation plugin.



As you can see from the image the orientation of the J-bolts is the same regardless of the wall, however it would not be a couple more lines of code to orient them all facing in or facing out or some other combination.  Curious how the contractors actually install these, is the orientation important

Typically no orientation, it is a "standard hook". If it is a poured wall I'll turn them so I can lay a rebar on the hook and wire tie it.

as an aside, many people still "wet stab" them in after the pour. This pushes any aggregate out of the way and often just the cream closes in over the top of the hook.

I've been talking to a few other contractors out there and most of them don't pay alot of attention to the orientation of the J-bolts into the concrete either, they let the concrete set up a bit and then stab them in.  The proper way to do this is position them and then pour later, but practice doesn't always follow the preferred/correct method.

I'm adding in the custom materials, stemwall foundation below is an example:



I will need to roll another revision probably tomorrow to get this update out there.

I was wondering about adding in the option for vents in the stemwall, for foundations with crawlspaces.  Any thoughts on this and what is standard construction in your locale as well as what type/brand of foundation vents/inserts are used.

The ICC codes call out a minimum of a one vent within 3 feet of each corner.  It shouldn't be to much trouble to create the openings in the stemwall and place some vents:



For a rectangular building (4 sides) should I place 4 vents or 8 vents?  Provide only the openings or also provide a generic foundation vent (lightweight geometry?)

Moving an opening is actually very easy within SketchUp, when it comes to a solid wall like this.

What is the typical header thickness between the top of the vent hole and the top of foundation?

Vent size seems to be 16"x8" for most vents I've seen.

With regards to vents there are the cheap plastic ones you can get a Home Depot or Lowes and and then there are a whole ton of more expensive louvered metal manufacturers of vents and flood vents.

Here they are typically right out of the top, a 3 sided cutout with the rim passing over. I put in the minimum and then block them off. No better way to rot the floor here than to vent with hot humid air into a crawlspace that is below dew point. If there is still high humidity then dehumidify. Basically a partially conditioned space.

The options for the crawlspace vents (if this option enabled) will be:

1.) Width (in.)
2.) Height (in.)
3.) Corner Distance (ft.)
4.) Top Fnd. Distance (in.)
5.) Max. Spacing (ft.)
6.) Location:  All Walls|Left/Right Walls|Front/Back Walls
7.) Vent Insert:  NONE|PLASTIC|METAL

The Max. spacing variable will determine whether to insert intermediate vents along the wall line.  The module will always place two vents per wall (if wall line selected), one at each corner and then equally space vents along wall line based on the Max. spacing variable.

I've done some reading on the effectiveness of foundation vents and I'm not sure I'm sold on the idea either.  In western washington, on the peninsula where I live, the high humidity is a major problem.  You almost need to have a dehumidifier otherwise your going to get mold.  Even when I lived in Mukilteo, I found standing water under the crawlspace in the house we lived in. 

I've been helping diagnose/remedy a problem here with a house, I know of several others that have had the same problem. There was standing water on the plastic on the dirt floor of a crawlspace. The floor above us had fiberglass insulation that was glistening wet. The portion of the joists exposed beneath the insulation was rotten, pull out the insulation and the wood looked fine, fresh and bright. The joists were sistered with treated and the girders replaced. The gutter and foundation drains were reworked/checked and everything was dried out with. I was called out again and it had puddles on the plastic again. A dehumidifier is under there now and it seems to be under control. If they run an AC, this homeowner rarely does, The joists exposed to the damp air are even colder and further below dew point.

Just another of those problems that needs to be addressed locally rather than a blanket adoption of the IRC.  It seems that earthquake zones are accepted criteria but not zones for high humidity. 

The vent module seems to be working fairly well:



If you set the top distance to zero the vents are right up to the sill plate:



Notice the top bar is clashing with the vent cutouts. 

Version 1.0.8 - 03.23.2017
- Added crawlspace vent option to stemwall foundations.
- Added a "Materials" tab within the global settings; Auto material assigment (colors and textures) is now an option.
- Enabled materials for all foundation types.

Version 1.0.8 - 03.23.2017
- Added crawlspace vent option to stemwall foundations.
- Added a "Materials" tab within the global settings; Auto material assigment (colors and textures) is now an option.
- Enabled materials for all foundation types.
- Added a joist pocket option for stemwall foundations.



I've been putting off the joist pocket feature for a while but figured I could spend my Friday night and knock it out.  I doubt it will get much use except for certain builders in the State of Oregon.

The options for the joist pocket option are:

1.)  Pocket Width
2.)  Pocket Height
3.)  Pocket Depth (into the stemwall)
4.)  Pocket Spacing (default is 16" o/c, but can be set to any value)

If you use joist pockets with either the brick ledge feature or the crawlspace vents you need to realize that the geometry must be such that the various item don't clash.  For example the stemwall must be thick enough for a brick ledge and the typical 2.25" depth of the joist pocket. 

With vents and pocket joists there must be enough vertical clearance between the two otherwise the header will be too thin for the overlying floor joist.  One solution to this problem is to have the vents only on the front and back walls while the joist pockets are on the left and right walls.

The number of options and inputs is now a bit mind boggling and the code is also at a new level of complexity.  Taking all of this to a polygon shaped foundation will be a challenge but that is where it needs to go next.

Version 1.0.9 - 03.25.2017
- Added slab foundation type (rectangular outline only).
- Enabled full and partial width interior thickened slab footings.



View model here:

https://3dwarehouse.sketchup.com/model/f96ebc51-f099-4dcf-a7a8-b51055a67a7c/Basement1

The push/pull feature of SketchUp makes things like popping holes and creating extrusions really easy.  The garage door shown below is a good example of this.  I've boxed out a section in the stemwall for the door and also extruded a piece of the slab out over top of the stemwall. 



The problem arises when the top rebar runs through the door opening.  Basically I need to create an opening tool that will remove the rebar as well as the concrete.  A virtual concrete saw cutting tool, too bad the boolean operations are not standard with SketchUp Make, this would make my life easier.

Finally got some time to work on the polygon tool in the foundation plugin, starting with the easy one which is the basic slab.

I've got it working for the concrete but the problem is the rebar, see image below:



The only way I can see to create the rebar is to use the solid boolean tools (ie. Subtract), however that is only available in the Pro version of SketchUp so the polygon tool would really only be useful or workable in the Pro version of SketchUp.  Unfortunately, I don't have enough extra cash at my disposal to even purchase the pro version so I am now at a standstill on this since I can't test or debug it further.

You can literally draw any shape you like but the rebar is configured to always align (parallel) with the edge created by the first and second points. 

As can be seen in this polygon shape the rebar could be potentially cut in multiple places.  The subtraction method makes the most sense but since I don't have that luxury I am working on a different algorithm for putting the rebar only within the concrete and so that it has at least 3" of ground clearance on the sides.

Haven't figured out the best way to deal with the slab reinforcement yet but I've moved on to start putting together the polygon tool for the Slab-on-Grade.  Since the offset line tool is not exposed in the API I've decided to try and use TIG's SmartOffset plugin as a starting point.  Unlike the rectangle tool I probably won't have a bend radius on the footing bars, at least not initially.  At some point I would like to figure out a plugin or some code that will automatically apply a radius or fillet to two lines/edges, I'm surprised that this functionality is not already built into SketchUp.

The way I will create the SOG is extrude the slab and then use the follow me tool for the footing, then union the two solids together, fairly simple.  Any shape or size of SOG will be possible.  The basic input (Non-Graphical User Interface) will only allow the entry of one internal footing however I am planning on implementing a Webdialog GUI that will allow the user to create as many interior footings as required and also allow them to even cross each other in grid patterns (ie. X-dir and Y-dir).  Things are going to get interesting with this plugin.

The GUI will allow the user to better preview the location and start and end points of the interior footing(s) which will make the entire process much more intuitive and easier to use.

Anchor bolts along the perimeter of the SOG will also be implemented.  Hoping to have all of this done by the end of the week, and as time allows.  I may have to simply disable the slab mesh/rebar until I can figure out a way to trim it without forcing the user to SketchUp Pro.

The slab on grade concrete is working great, that was easy.  Now I just need to work on the rebar in the perimeter footing and the anchor bolts as well as the optional garage curb.

Any shape is possible even a circular shape by selecting points along an arc.  Now I really need to get the wall plugin going with the same polygon tool that is smart enough to handle typical 90 deg. corners and non-orthogonal corners.



Curved walls and roofs though are still a bit of stretch, but I can see we need to eventually go that direction as well to make everything complete.