• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

How high can a stem wall be?

rockb

Registered User
Joined
Oct 25, 2020
Messages
2
Location
Bay County FL
I am looking at building on a waterfront lot. The house has to be at least 4' above grade but I am thinking of going 5'-6'. I was talking to a builder who built my uncle's house next door at the same time someone else was building a couple lots away. The house a couple lots away was build with a stem wall that was back filled with dirt. The builder said that they did not do it right and that the force of the dirt was causing the stem wall to bow out.

Is there a limit to how high you can build a stem wall and back fill with dirt before it becomes unstable or did the builder of the other house just not do something correct with the stem wall?

Alternately would there be any advantage of using Pier & Beam (cost advantage or other)? House will be gulf coast of Florida 30' away from a saltwater bayou. The last major hurricane to cause major storm surge here had 4'-5' of surge where we are planning on building the house.
 

cda

Sawhorse 123
Joined
Oct 19, 2009
Messages
19,058
Location
Basement
Welcome

Give it a few days.

We do have a few Fla experts on the site.

Not a wall expert, if it was my house, I would have an engineer design it, no matter how high,,, and I would have them over design it!!!

Seen a few houses go over the cliff, or down the gully.
 

Paul Sweet

Sawhorse
Joined
Oct 17, 2009
Messages
1,417
Location
Richmond, VA
Did they backfill the house a couple lots away then pour a slab over the backfill? If so, the stem wall would have to be braced from the outside until the house is framed and has put some vertical load on the stem wall to offset the bending from the backfill.
 

classicT

Sawhorse
Joined
Aug 2, 2017
Messages
1,589
Location
Washington State
No limit, but engineering would get involved at some point there are tables in the IRC, but if you are on the coast of Florida, engineering may already be required, if not recommended....
I disagree.... the limit is 4-ft.

If a wall supports more than 4-ft of unbalance fill, and is not supported at top and bottom, then it must be designed by a licensed engineer. In the case the OP has put forth, the slab on grade should be tied into the interior slab-on-grade floor by rebar.

R404.1.1 Design Required
Concrete or masonry foundation walls shall be designed in accordance with accepted engineering practice where either of the following conditions exists:
  1. Walls are subject to hydrostatic pressure from ground water.
  2. Walls supporting more than 48 inches (1219 mm) of unbalanced backfill that do not have permanent lateral support at the top or bottom.
 

Msradell

Sawhorse
Joined
Jul 23, 2011
Messages
906
Location
Louisville Kentucky
Why would you backfill it and pour a slab on grade? You would be better off using trusses (wood or metal) to span across the area to create a crawlspace. Especially if you used wood it would make a floor that was much more comfortable to walk on instead of a hard concrete floor. He would also gain storage space.
 

steveray

Sawhorse
Joined
Nov 25, 2009
Messages
7,706
Location
West of the river CT
I disagree.... the limit is 4-ft.

If a wall supports more than 4-ft of unbalance fill, and is not supported at top and bottom, then it must be designed by a licensed engineer. In the case the OP has put forth, the slab on grade should be tied into the interior slab-on-grade floor by rebar.

R404.1.1 Design Required
Concrete or masonry foundation walls shall be designed in accordance with accepted engineering practice where either of the following conditions exists:
  1. Walls are subject to hydrostatic pressure from ground water.
  2. Walls supporting more than 48 inches (1219 mm) of unbalanced backfill that do not have permanent lateral support at the top or bottom.
Like I said...No limit, but engineering required at some point...I would call a wall with no lateral support a retaining wall, not a stem wall....
 

Paul Sweet

Sawhorse
Joined
Oct 17, 2009
Messages
1,417
Location
Richmond, VA

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,705
From a legal perspective it is not the role for the building code and the local building department to say when a licensed engineer is required. That question is answered by the state laws licensing engineers.

From a technical perspective there is no effective limit if it is engineered and complies with the applicable code provisions. What you think of as a stem wall can be easily transformed into a retaining wall by making the base wider and varying the reinforcing steel.
 

classicT

Sawhorse
Joined
Aug 2, 2017
Messages
1,589
Location
Washington State
From a legal perspective it is not the role for the building code and the local building department to say when a licensed engineer is required. That question is answered by the state laws licensing engineers.

From a technical perspective there is no effective limit if it is engineered and complies with the applicable code provisions. What you think of as a stem wall can be easily transformed into a retaining wall by making the base wider and varying the reinforcing steel.
Are you going to put forward the code amendment to have "designed in accordance with accepted engineering practice" removed from R404.1.1?

Or what about from R301.1.3, R404.5.1, R502.11.1, R608.9.2, R610.1, etc.? Like it or not, the I-Codes do have provisions that indicate when a licensed engineer is required. And the codes, at least in my home state, are adopted as laws that are no different than the state licensing laws that you speak of.

We all go by the adage that if it isn't prescriptive, go hire an engineer. The IRC only allows the prescriptive construction of unbalanced walls to 4-ft. More than that, it is not prescriptive... go hire an engineer.

R404.1.1 Design Required
Concrete or masonry foundation walls shall be designed in accordance with accepted engineering practice where either of the following conditions exists:
  1. Walls are subject to hydrostatic pressure from ground water.
  2. Walls supporting more than 48 inches (1219 mm) of unbalanced backfill that do not have permanent lateral support at the top or bottom.
 

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,705
I am not advocating that engineering be done by non-licensed individuals. I am simply stating that it is inappropriate for the building code to regulate engineering.

The reason that the building code cannot define when an engineer is required has to do with the fact that the licensing provisions are defined by the legislature and the building code is a regulation or local ordinance. The state has not given local jurisdictions the authority to regulate the practice of engineering. State statutes control over regulations or local ordinances. Not all laws are equal. So while the building code might have such requirements they are null and void. This would be similar to a city passing a law legalizing slavery.

Now I can hearing some claim that their jurisdiction can regulate engineering because of home rule. Home rule authority can only exist if provided for in the state constitution or possibly authorized by the legislature. I suspect that if you look at your state constitution there are limits on the home rule authority of the local jurisdiction. If you disagree then I suggest you send a letter to your state agency that regulates the practice of engineering stating that you will be regulating the practice of engineering. Enjoy the litigation.

The IRC provision is only a limit is you do not realize that you can also invoke the IBC provisions.
 

classicT

Sawhorse
Joined
Aug 2, 2017
Messages
1,589
Location
Washington State
If you disagree then I suggest you send a letter to your state agency that regulates the practice of engineering stating that you will be regulating the practice of engineering.
Perhaps why you and I do not see eye-to-eye, is that as a local AHJ, we do not adopt the I-Codes. In WA, the state adopts the building codes and all local jurisdictions are forced to do the same. Most double down on the states adoption, and put it in their own municipal code with amendments for fee schedules and such.

So in the fact that the state adopts the building codes in WA, the building code has the same legal weight as the laws regulating the practice of engineering. Both are legally adopted at the state legislature. Both are RCW (Revised Code of Washington) statutes/laws.
 

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,705
Does the legislature in WA directly adopt the building code or does it delegate that task to a state agency? When the legislature delegated the adoption of building regulations to a state agency did they also delegate to that agency the regulation of engineers. Separately the legislature explicitly delegated the regulation of the practice of engineering to a separate agency. In most places this means that the agency adopting the building regulations does not have the authority to regulate the practice of engineering.

There is a basic legal principle that regulations are subservient to statutes directly adopted by the legislature.

I repeat my suggestion, if you disagree then I suggest you send a letter to your state agency that regulates the practice of engineering stating that you will be regulating the practice of engineering.

We need to pay attention to how model codes such as the IBC get developed and then adopted. Model codes are not a legal requirement and the author (ICC) can put in it whatever they want. The membership of ICC is not sophisticated in these legal issues and they put somethings into the model code that may conflict with individual state laws. The state agency or a local jurisdiction then adopts the model code but does not review it to verify that there are no conflicts with existing state laws. Thus it is conceivable that there will be conflicts with the adopted regulations and state statutes directly adopted by the legislature.

If we adopt the principle that they are all laws, then we have effectively given ICC the authority to control the law on any issue. Surely this will be of concern to anyone that is concerned about state rights.

I hope we recognize that in this scenario that there are limits on what can be in the building code. So let us do a test, have ICC insert a provision in the IBC exempting building officials from having to pay state income taxes or file tax returns, which should be popular among the membership of ICC. Inevitably some state agency will adopt the IBC without removing this provision. Then the building officials will not file state tax returns. Will your argument protect you when you are accused of not filing your tax return or will we find building officials going to jail?

We should remember that building codes are about regulating the buildings not the individuals involved with the construction process.
 

classicT

Sawhorse
Joined
Aug 2, 2017
Messages
1,589
Location
Washington State
First off - I speak only to the laws of WA, as that is where I am educated. Laws in any other state may be different.

Does the legislature in WA directly adopt the building code or does it delegate that task to a state agency?
The State Legislature has delegated the SBCC (State Building Code Council) to draft amendments and review, but the State Legislature has the final vote to adopt.

What you must also consider is the Administrative Code. In WA, we have the RCW (the laws) and the WAC (administrative code). The WAC lays out the groundwork for intent and legal authority, and basically tells you how to apply the RCW.

I agree that I cannot regulate the practice of engineering. I can require engineering where not prescriptive per the I-Codes. If someone other than a licensed engineer completes the engineering, I am instructed via the WAC to report them to the State Department of Licensing. Thus, I do not have the ability to regulate, just a responsibility to require engineering be done by a licensed party. (Not so much different than requiring a contractors license)

I repeat my suggestion, if you disagree then I suggest you send a letter to your state agency that regulates the practice of engineering stating that you will be regulating the practice of engineering.
Your above quote is ridiculous. Why would I do that? We are not regulating the practice, we are merely verifying that those practicing engineering are licensed to do such. Failure to be licensed will place the permit on hold, and the drawings can be forwarded to the State Dept. of Licensing. They can then review and persecute for practicing without a license.

Model codes are not a legal requirement and the author (ICC) can put in it whatever they want.
In WA, after the state amends, they are adopted in full text as law. They are thereby legal requirements. As example, see RCW 19.27.031 and WAC 51-50.

The state agency or a local jurisdiction then adopts the model code but does not review it to verify that there are no conflicts with existing state laws.
In WA, they do. The SBCC amends, then the State Legislature reviews for conflict and vets the legality.

I hope we recognize that in this scenario that there are limits on what can be in the building code. So let us do a test, have ICC insert a provision in the IBC exempting building officials from having to pay state income taxes or file tax returns, which should be popular among the membership of ICC. Inevitably some state agency will adopt the IBC without removing this provision. Then the building officials will not file state tax returns. Will your argument protect you when you are accused of not filing your tax return or will we find building officials going to jail?
While this is a preposterous suggestion, I get your intent. In this proposition, the Building Official would be protected and technically ok, because they could directly point to a section of code, which is law, and show that they have complied. The State Legislature would be surely embarrassed as they would have been found in dereliction of their duties in allowing such an amendment. After all, it is the State Legislature who is responsible to vet the SBCC's proposed code for legality.
 

Mark K

Platinum Member
Joined
May 12, 2010
Messages
1,705
I have done further research into the laws of the state of Washington and have consulted with a source in Washington and what I have found is that the state has adopted a fairly conventional system of administrative law where the legislature defines some general criteria and then delegates the formal adoption of the regulations, which are laws, to a state agency. Under this system if there is a conflict between the statutes adopted by the legislature and the regulations adopted by the SBCC the statutes govern. Not all laws are equal.

I suggest that your understanding of the law in Washington is flawed.

In addition contrary to your claim a building code provision allowing the building official not to pay state taxes would be illegal since when the SBCC was given authority to adopt building regulations they were not given the authority to adopt regulations related to tax law. So the building official who pointed to a provision in the building code could go to jail for not paying taxes. Just because something is in the building code does not make it legal.

The legislature does establish that the IBC and IRC are the basis of the building regulations but does not define the version of the model code to be adopted. The legislature does not directly adopt the building code The legislature delegates to the SBCC the selection of the version of the model code and the modification of the model code. The state building regulations go into effect when adopted by the SBCC without any direct involvement of the legislature. The legislature does not review or formally endorse the results of the SBCC's effort. If the legislature does not like what the SBCC has adopted, their only option is to pass a new law addressing the problem.

While the RCW lists the IBC and the IRC, this in the absence of the actions of the SBCC does not make them law. It is well established that the state cannot adopt a future version of the model code that at the time of adoption did not exist in a final version. When adopting a standard it is always necessary to specify the version of that standard which is being adopted.
 

classicT

Sawhorse
Joined
Aug 2, 2017
Messages
1,589
Location
Washington State
The state building regulations go into effect when adopted by the SBCC without any direct involvement of the legislature. The legislature does not review or formally endorse the results of the SBCC's effort. If the legislature does not like what the SBCC has adopted, their only option is to pass a new law addressing the problem.
Mark - We will not see eye-to-eye, and that is ok.

But just know, the statement above is false. Thanks for your input though.
 

tmurray

Registered User
Joined
Jun 10, 2011
Messages
1,923
Location
NB, Canada
I would disagree with the assertion that the state would have to directly adopt the building code. Where the state has the authority to adopt a code, they also have the authority to delegate that adoption to another body. Where the code has conditions which would require the involvement of an engineer, one could also conclude that the state has delegated this to the same body specifically in relation to the building code.

The alternative is truly unthinkable, that there is no requirement for an engineered design police-able by building officials. We would be required to issue permits on items that we know should have an engineer involved, but does not. At best, we could advise those responsible for enforcing the regulations of the practice of engineering of the violation, but only if it does not violate privacy laws.
 
Top