Structural Sizing (Beams, Joists, etc.)


 Share

Recommended Posts

I have been in the residential construction industry for more than 15 years and am considering purchasing Chief to begin drawing plans for others.  In my Midwestern location, the local building departments do not require sophisticated building plans.  A floor plan, elevations, and foundation plan is all that is needed to get building permits.  The engineered trusses and floor joist/beam plans, stamped by a licensed engineer, must be onsite at the time of the building department inspections.  However, these engineered plans do not need to be part of the building plans that are submitted to the building department to obtain a building permit.  These do not get engineered until the lumber package provider submits an order for these items.

 

I am not a licensed engineer and would be working as a draftsperson.  When drawing plans for others (builders and homeowners), how do most draftsman determine structural requirements such as the proper sizing and spacing of joists and beams, location of crawlspace piers, etc.? 

 

I have the latest International Residential Code book, our local code, with the tables for requirements for load, deflection, sizing, spacing, etc. and have much experience in the industry.  However, I am curious as to how most draftsman determine these items for the plans that they draw.

 

Do these items have to be specified in Chief or will the software be able to make these determinations?  Is there sizing/spacing software that others use where you provide input and these structural items are determined?

 

I'm just trying to determine the most commonly used method, accurate, and most simple way of obtaining the structural requirements for each set of plans.

 

Thank you to all who respond!

Link to comment
Share on other sites

CA does not do any engineering.

I would suggest you use your tables, etc. to get your plan going and then when you think you have it, take your plan to a local engineer for him to review. They will help you with the engineering on loads, shear walls, hold downs, strapping, etc. They are very reasonably priced for the service they provide, I have found.

For Boise Cascade products, I use bc Framer, and bc Calc. BC Calc is available online, BC Framer needs a referral to use.

Link to comment
Share on other sites

I often do prescriptive structural design for clients here in southern California as long as the Building Official (BO) will allows it to be done prescriptively and not require an engineer.

 

Here the structures I do like this will be relatively simple structures without too large of openings, spans, heights,  etc.

 

I don't use any software other than a PDF viewer to check out tables and such in the California Residential Code (CRC).

 

Some times the BO will require that some aspects of my prescriptive design be done by an engineer so that they can cover their derriere.

 

Andy.

Link to comment
Share on other sites

I use StruCalc for more complex conditions and the excellent but free Forte software from Weyerhauser for simple wood members and LVLs.  I typically include the report PDFs on the drawing sheets as well.

 

http://www.woodbywy.com/software/forte-software/

 

This is my preferred solution also. The IRC also has good tables and references, particularly for prescriptive ICF solutions.

Link to comment
Share on other sites

Any needed engineering or even any questionable spans are handed over to my engineer who will mark up the plans and get me a set of calcs. for plan submittal. Why would someone want that liability when an engineer is employed for exactly that reason?

Link to comment
Share on other sites

Any needed engineering or even any questionable spans are handed over to my engineer who will mark up the plans and get me a set of calcs. for plan submittal. Why would someone want that liability when an engineer is employed for exactly that reason?

 

Anything outside of someone's competency should absolutely be handed off. However, most engineers also use software tools to run their calcs - if you know the design principles and how to properly apply the software, then it can save a lot of time, coordination, and fees.

Link to comment
Share on other sites

Anything outside of someone's competency should absolutely be handed off. However, most engineers also use software tools to run their calcs - if you know the design principles and how to properly apply the software, then it can save a lot of time, coordination, and fees.

 

 

Words to live by!

 

Besides, here in Indiana, there are only a handful of structural engineers that are even willing to work with residential. Everything needing to be engineered around here (some beams, i-joists, trusses) goes through the lumber yards and they send them off to a supplier.

Link to comment
Share on other sites

In theory, following prescriptive code IS engineering although I often wonder who would take the hit if it were incorrect? The BO or ICC would be my guess. My attorney tells me as long as you follow "common practices" it's hard to sue.

 

If a designer misunderstands or omits something following code they are liable since they were not qualified to design. That is why I think it is a good idea to create an E&O insured entity as a designer. I often wonder how it is then DIY home owners can design or modify, if they cause personal injury who is on the hook? If someone is visiting while they own they are. If it happens after sale and home disclosures the new owner unless the old failed to disclosed, is my guess.

 

A PE only takes liability for stress analysis. In residential seems like a waste of money when there are code paths, unless using some alternative materials IRC points to a PE. I'm in CA now visiting that is another country, ridiculous!  

 

Running FEM(Finite Element Models) and interpreting them takes an engineering education and experience, rare otherwise, and agree why take the risk in having any part of that legal liability in part or whole especially without an E&O legal entity. Silly!

Link to comment
Share on other sites

If a designer misunderstands or omits something following code they are liable since they were not qualified to design.

 

We are qualified to design, even licensed Architects make mistakes, and are liable even more than designers. That's why the actually have insurance for them. Anyone can be sued as we all know.

Link to comment
Share on other sites

even licensed Architects make mistakes, and are liable even more than designers. That's why the actually have insurance for them. Anyone can be sued as we all know.

 

IRC defines where there is a requirement to be licensed to practice design. (eg: above duplexes, above three stories, commercial requires one), otherwise, if you are following code licensed or not omit or make an error trust me you could be liable. When the jurisdiction decides to "adopt, amend" it is now state law enforceable. Anyone can purchase E&O. The underwriter will look at your experience/licenses to determine cost. Yes, anyone can be sued, No, not all Designers are created equal. Saving money on practicing Design/FEM/Etc may not be worth the risk. All it takes in one day in court and if your assets are not protected say good by to them. I seen this in CA construction contract law more than any other state. It is a good idea to not go cheap on your contracts either, hire an experienced state attorney and hold on just incase. 

Link to comment
Share on other sites

Of course Designers don't do those you listed ,but they can with an engineer. California goes by the business and profession code which allows anyone to draw residential 1,2, and 3 story. Can't find insurance for Designers here.

Link to comment
Share on other sites

Of course Designers don't do those you listed ,but they can with an engineer. California goes by the business and profession code which allows anyone to draw residential 1,2, and 3 story. Can't find insurance for Designers here.

I wouldn't do that third story if you don't have a license. CA B&PC 5537. (a) This chapter does not prohibit any person from preparing plans, drawings, or specifications for any of the following: (1) Single-family dwellings of woodframe construction not more than two stories and basement in height.

Link to comment
Share on other sites

If you are doing them as an independent designer, and signing your own drawings, then you are doing them illegally. Period. You can provide drafting services TO the engineer who is acting as the prime design professional, of course. Or maybe you are confusing a third story with a habitable attic.

Link to comment
Share on other sites

IRC defines where there is a requirement to be licensed to practice design. (eg: above duplexes, above three stories, commercial requires one), otherwise, if you are following code licensed or not omit or make an error trust me you could be liable. When the jurisdiction decides to "adopt, amend" it is now state law enforceable. Anyone can purchase E&O. The underwriter will look at your experience/licenses to determine cost. Yes, anyone can be sued, No, not all Designers are created equal. Saving money on practicing Design/FEM/Etc may not be worth the risk. All it takes in one day in court and if your assets are not protected say good by to them. I seen this in CA construction contract law more than any other state. It is a good idea to not go cheap on your contracts either, hire an experienced state attorney and hold on just incase. 

 

There is nothing in the IRC that states any requirement of who can design what type of building(​not correct my bad). The IRC does state liability but only as it refers to the Building Official and Building Inspectors.

As far as needing engineering, the IRC states you do not need engineering as long as you can meet the prescriptive requirements of the IRC. You can have a combination of both prescriptive and engineered path to drawing development.

I submitted 1 plan recently in seismic zone D1 using the prescriptive method with no engineering. It was approved 4 days ago.

  • Upvote 1
Link to comment
Share on other sites

If you are doing them as an independent designer, and signing your own drawings, then you are doing them illegally. Period. You can provide drafting services TO the engineer who is acting as the prime design professional, of course. Or maybe you are confusing a third story with a habitable attic.

No, I do sign my drawings b/c the cities want me to along with my engineers stamp. do it that way for 40 years without any problems what so ever. Richard you are just wrong about a lot of this. You are allowed to sign your own plans period.  It's a requirement around here. You always have a cow about this stuff, just cool and learn the facts.

Link to comment
Share on other sites

There is nothing in the IRC that states any requirement of who can design what type of building. 

R106.1 states: "The construction documents shall be prepared by a registered design professional where required by the statutes of the jurisdiction in which the project is to be constructed." You have to look at the state code to find out what structures are exempt from licensure.

Link to comment
Share on other sites

Legal this, illegal that... You guys from CA sure have the hoops to jump thru. Have any designs by Perry collapsed or not function properly? If there is no problem with what he is doing, why take offense?

Do you realize there are still places in this country where a man can build without government permits? And just think, no one is dieing from collapsing buildings there.

Some of you are probably scaring the OP out of doing design work with some of these comments. :-)

Link to comment
Share on other sites

It's guys like Richard that wants to put all us designers out of business. I remember back in the day the AIA tried to get rid of designers so they grandfathered designers to licensed Architects, I have friends that went that way, some very successful ,and some not ,but they tried to eliminate designers and ,it didn't work so some Architects have been complaining ever since. It's never going to happen here. Now all they did was infiltrate their special group, with not so competent Architect's.  

Link to comment
Share on other sites

No, I do sign my drawings b/c the cities want me to along with my engineers stamp. do it that way for 40 years without any problems what so ever. Richard you are just wrong about a lot of this. 

You don't get to make up laws just to suit what you want to do. If you've got a code citation that says an unlicensed person can design three-story buildings, cite it. If not, it's just a bunch of hot air on your part, even if you haven't been caught yet. I don't really care since it's YOUR ass on the line, but if you are designing actual three-story buildings, then you are living on borrowed time, IMO. Have fun! 

 

BTW, here's a sample from the California Architect's Board enforcement actions: "HERMOSA BEACH—The Board issued a two-count citation that included a $4,000 fine to Jonathan Starr, dba Starr Design Group, an unlicensed individual, for alleged violations of BPC 5536(a) (Practice Without License or Holding Self Out as Architect). The action alleged that Starr executed an agreement offering to provide design services for a new three story over basement single-family residence located in Manhattan Beach, California. Starr also executed an agreement offering to provide design services for a new three story over basement single-family residence with attached two-car garage and roof deck located in Hermosa Beach, California. The projects did not satisfy the criteria for an exempt project type as defined in BPC 5537(a), and required a licensed design professional for preparation of plans, drawings, or specifications. Starr paid the fine, satisfying the citation. The citation became final on July 29, 2014."

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share