Drafting standards for showing wood framed buildings in plan 2

[JTdaMB]

Hey dudes and dudettes ...

I am an ex-framer of custom homes (10-years) turned structural engineer (17 years). I have worked for three structural engineering firms so far and each one has had differing structural drafting standards for showing wood framed buildings in plan. I will try to explain each one:

Method 1:

Foundation Plan--cut through the center of all window and door openings at the first level. You see the wall sections from first level, jamb lines from first level, but no wall headers
Second Floor Plan--cut through the center of all window openings at the second level. You see floor framing and wall sections from second level, jamb lines from second level, jamb lines from first level (dashed if openings do not stack), and wall headers from first level.
Third Floor Plan--cut through the center of all window openings at the third level. You see floor framing and wall sections from third level, jamb lines from third level, jamb lines from second level (dashed if openings do not stack), and wall headers from second level.
Roof Plan--cut above roof. You see roof framing, walls dashed and headers from third level.

Main drawback (other than it looking like a drafting error if openings do not stack) is that it takes two architectural background to create one structural floor plan.

Method 2:
Foundation Plan--cut through the center of all window and door openings at the first level. You see the wall sections from first level, jamb lines from first level, but no wall headers
Second Floor Plan--cut UNDER the sole plate of the second floor walls. You see floor framing from second level; all first level walls dashed and wall headers from first level.
Third Floor plan--cut UNDER the sole plate of the third level walls. You see floor framing from third level; all second level walls dashed and wall headers from second level.
Roof Plan--cut above roof. You see roof framing; third level walls dashed and headers from third level.

Main drawback is that it is confusing as hell and does not appear to reflect what's going on in the architectural drawings

Method 3:
Foundation Plan--cut just above wall headers at first level. You see wall sections from first level; all window/door openings and corresponding headers at first level.
Second Floor Plan--cut just above wall headers at second level. You see floor framing and wall sections at second level; all window openings and corresponding headers at second level.
Third Floor Plan--cut just above wall headers at third level. You see floor framing and wall sections at third level; all window openings and corresponding headers at third level.
Roof Plan--cut above roof. You see roof framing; all walls below as dashed; no headers

Main drawback is that it is more difficult for structural engineers to track loads through building if openings do not stack.

What is your experience?
How do your firms show wood framed structures in plan?
What do you believe is the most efficient way?

 

[msquared48]

On all levels, I cut the plan midway between the floor levels to show all openings with beams and headers below.

Mike McCann, PE, SE (WA)

 

[JTdaMB]

Thanks Mike ... so, Method 1 then?

 

[msquared48]

yup...

Mike McCann, PE, SE (WA)

 

[EngineeringEric]

Kind of like 2 i guess...? I never show framing on my foundation plan though.

-Foundation is foundation and doors (pour through only...)
-Next level framing (floor or roof) shows the wall supporting the framing and all headers, post, beams that are required. bearing lines above are dashed if not supported by a wall below.
-roof is same as a floor but with slopes shown.

 

[TehMightyEngineer]

Method 2: easier to design and in my (limited) opinion easier to build. This way a framer can see what each level of framing has and what supports that level. Combined with isometric views, details, and section cuts this is what I prefer and find easiest to use.

Maine EIT, Civil/Structural.

 

[JTdaMB]

EngineeringEric,

So you would call out your shear wall and holdown info on the second level floor plan?

 

[msquared48]

The hold downs for the shear walls in the story between the roof and floor below would be shown at the floor framing of the story below, where they are actually placed. This can be a little confusing if you are looking at only one level of framing, but when the various levels are stacked, as a structure is, then it becomes clear.

I normally like to intermix the architectural plan with this method of structural framing plans during the design process as all the vertical and horizontal discontinuities do show up.

Mike McCann, PE, SE (WA)

 

[TehMightyEngineer]

Another advantage of Mike's method (and mine) of putting the holddowns on the drawing of the level below is structures are (hopefully) built from the ground up and a framer will have all the information he needs on a level by level basis and doesn't have to flip too much between sheets until he moves onto the next level.

Maine EIT, Civil/Structural.

 

[JTdaMB]

Thanks for the feedback guys,

As an ex-framer, I can tell you that I can build anything you put in front of me ... no matter where/how it is shown. Of course, drawing clarity and organization is always a plus. Same is true of the GC's/Framers in the Pacific NW (area where I practice) as every engineering firm out here seems to show wood buildings in a slightly different way.

As a structural engineer looking for more efficient ways to produce clear, concise, and constructable documents ... I have to say that I prefer Method 3. It has a one-to-one correspondence with the architectural drawings (i.e. their first floor cad background is our first floor cad background, etc.) ... and it saves drafting time on wood framed projects where our fee is typically low and the projects are typically complex. Everything required to construct a level, and everything required to support the next level up, is shown on one drawing.

The only drawback of Method 3, as I see it, is tracking loads during design if openings do not stack. However, the architectural drawings will ALWAYS have exterior building elevations that we can use as reference (for non-stacked openings) so it really only becomes an issue for the interior bearing walls.

 

[EngineeringEric]

For a two story house, it goes:

-Foundation and first floor framing
-First floor walls and the system that they support (second floor joists)
-Second floor walls and roof

Hold downs will be shown on each plan as shown. I often show the location on the foundation since they need to be embedded or attached to the foundation.

 

[jayrod12]

I'm in with method 2 generally and pretty much exactly how EngineeringEric described.

 

[Archie264]

Something to be aware of is that often in residential construction architects show second floor structural members on the first floor plans and show roof structural members on the second floor plan, etc. I.e., they might have a note on the second floor plans referencing building a soffit around your beam above. If they show the beam then to us structural types it looks like a beam below. It can be confusing and is something to watch out for.

 

[msquared48]

Structural engineers are always on top of things. That's why the beams and walls are below.

Mike McCann, PE, SE (WA)

 

[JTdaMB]

Hahaha ... nice

 

[RHTPE]

As an engineer with 45 years in the construction industry and always producing my own drawings, I feel compelled to comment.

First, to hell with common convention. Focus on what the guy in the field has to build, particularly if you want it built according to your plan.

1. Foundation plan shows exactly that - footing & foundation walls up to the underside of the level it supports.
2. First floor plan shows the first floor structure period. Include all supporting structure elements if the foundation walls do not continue up to the first floor sills. Anything above the top of the joists is irrelevant for the guy constructing it. If there are considerations for subsequent construction above the joists, call it out or provide the appropriate details.
3. Second floor plan shows the second floor structure and all that supports it, i.e. from the top of the first floor joists up to the top of the second floor joists. Again, if there are considerations for subsequent construction above the joists, call it out or provide the appropriate details.
4. Roof plan shows all structural elements from the top of the second floor joists on up.

This is just my NTBH opinion and how I approach a structure. Others may disagree. What matters is how easy it is for the guy who has to build it. It may require some coaching for him to understand your drawing, but once he does, it will go smoothly.

I find that overlaying the structural plans on the architectural plans can often be confusing as hell for the field. Unfortunately we engineers are always squeezed on time and fees and the focus is sometimes more on how to analyze and less on how to build.


Ralph
Structures Consulting
Northeast USA

 

[RFreund]

I would add that we have done similar to Ralph, with a separate first floor plan and even a separate ceiling and roof framing plan once and a while.

EIT

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