Help! Want to expand the 20x30 w/loft into a 24x40 w/loft.

[Rys]

I've had my plans for some time now. Am now ready to build. My dilemma is I suck at computer stuff! 
Was wondering if anyone else has done this that could help me with plans? Staying with the same open concept as original plan. Want to add a shed dormer upstairs for more headroom on one side only. Would like to incorporate small open area at top of stairs for a reading loft. Build will be on a walk-out basement butted up into a hillside. Would also like to do a hallway exiting out the long end of the house through a mud room. Bedroom/pantry on one side, bath/laundry on the othe side. Any suggestions or help greatly appreciated!

Rys

[John Raabe]

By going wider than the 20' width of your plans you will need to check with the lumber supplier to see what they can supply for joists. You might also check if they know of someone to help with modifying a stock plan as you will have a new layout too. Also, you will likely change the loft as it could have more headroom.

[Rys]

HI John!
That's kind of my problem, without hiring someone to completely redo things, I'm at a standstill. 
I live in Podunk, USA. Not many resources here.
I was trying to avoid getting an architect involved to save money, of which I am in short supply! 
We were going with I joists for the floor and hopefully parallel chord? roof trusses. The floor plan will stay pretty much the same as the 20x30. I thought by using the I beam floor joists we could span the twenty four feet, keeping an open floor plan,except where the stairs come through? I'm assuming at least one if not two posts would have to run from the stair opening at the loft down to the basement and be supported by a poured footer?
Looking for someone in our group who has built something similar.
Any help is greatly appreciated!
Rys

[MountainDon]

Length is easy to increase, width increases need engineers.  If you go with engineered floor and roof trusses, the truss company will do the engineering that is required. You need to provide them the width, one story vs 2 story, location or snow load... they'll know what details they need to engineer the trusses.  They will also provide the paperwork that will satisfy any building inspection departments, once you have paid them. So look around for a nearby manufacturer.

[Don_P]

What are your building dept requirements for plan submission... or do you need to submit a set? Let's see what you have so far.

[Rys]

My building dept accepts hand done drawings. I was going to try and use the plan that I purchased here and make it wider and longer with the appropriate types of floor joists to span the extra width. Still going with the ten foot walls and partial loft area for an upstairs bedroom. Want to incorporate a small shed dormer to one side for better headroom and Windows.
With the added width I'd like to add a hallway out to the end of the house between the bedroom area and bathroom to act as our main entrance from the parking area.
I would gladly pay someone from the boards to help with the modifications. They are just beyond my capabilities!

[Don_P]

I've spanned 24' with open web joists a couple of times. One client then went over the floor with another layer of subfloor with seams offset and screwed down and together well. That mass calmed down the snare drum effect those long spans can have. I went to an engineering training session and talked with an engineering professor. He had worked it out to annoying vibration frequencies and mass was one way he suggested to calm those floors down. Upshot of that is, those long spans do come at a serviceability cost. In the basement I'd accept a center line of posts supporting a girder and break the span of the main floor down to 12'.

Upstairs I would investigate attic trusses. If they are built cantilevered with a 2' overhang they are essentially at the same elevation as common rafters on a 2' kneewall. Typically they have the "wall" at 4-6' tall inside so on a 24' wide building the upper floor is 16-18' wide.

Well, no matter how it works you need to be able to receive drawings. Let's try something different. Download Sketchup and begin to familiarize yourself. For one thing learn to "save as" sketchup 2016... that is as far as my computer graphics can keep up. We can post snapshots of the screen for a plan but there is much more useable information there if you learn to rotate the 3d model on your screen and zoom in on a detail of interest. Being able to do that with a good drawing/ model during the build would hopefully be more pre-emptive than all of the "well you really should have done it this way"s.

Even a photo of a napkin with chicken scratches and dimensions is a start though...

[Rys]

Thanks for all the advice! 
Wish I could convince my husband that twent foot wide is plenty!
Will download sketch-up and see what I can do. I'm sure I'll have many more questions.
Rys. 

[Don_P]

While you are learning to crawl with sketchup go ahead and sketch what you know so far. With that rough hand sketch I can begin the sketchup model and post that for you to play with and take to the next level. Back and forth in an iterative fashion any number of people can input and try modifications to the sketch. As long as you keep a file when you start you can play to your hearts content and not risk "losing" anything.

I actually prefer at least 24' width, things seem to start clicking easier.

[Rys]

Will do. Thanks!

[Don_P]

It was too cold this morning for me and I wanted to play with this and Medeek's plugins. I certainly didn't do it expertly but trying to show the concept of what I'm thinking.



This is the sketchup file, you can download and save it. Open it in sketchup and you can manipulate it in 3d and draw on it.

http://timbertoolbox.com/cp/Rys1.skp

[Rys]

Thanks. Will do so when I'm at a computer.

[Don_P]

That works and keeps the floor clear, kind of cluttered and a marriage of components
Playing with the framing a little differently, stick framed roof with structural ridgebeam, dropped joists on tall walls, 2 interior posts. That was quick, the post locations and ridge loads would still need work.


File here;
http://timbertoolbox.com/cp/Rys1.1.skp

I could see potential for kicking out a dormer on the other side for stairs.

[Rys]

I love the version with the dormer. Would it be possible to do something like this with trusses?
I saw someone on in this group that used parallel chord trusses for a nice cathedral ceiling.
We were wanting a dormer only on the back side. Thinking about doing a skylight on the other side for light/airflow.
Could I use the stair opening to "hide" my support beams? Most of the loft space will be a bedroom.In front of that I'd like to incorporate an open area that looks down into the living room.That area will be where my stairs come to.
Wasn't able to open the file you sent on my I Pad. My son promised to get my new computer up and running for me. 

[Don_P]

The closest truss in Medeek's gallery is a scissor truss, when you sit down with the truss techs they will do the actual design. I've seen the truss sheet you speak of in someone's build thread.  So yes quite do-able. Anyway the 5 minute version in scissors;



A couple of neat things about sketchup, I drew the trusses in about 5 minutes with Medeek's plugin. All of these roof changes are part of the same drawing. I put each roof on its own "layer" and can turn on or off whatever layers I want to view as I work.

[Rys]

Love it! Gonna have to prod my youngin!   

[Don_P]

This is a screenshot of sketchup and this model. I've pulled out the "default tray" of tools showing layers and entities. I've clicked the arrow icon on the scissor truss "component" and it highlighted in blue. The entity info tab identified it as the truss assembly, assigned to a layer called "scissor trusses". Under the layers tab at the bottom of the list is a layer I created, using the "+" button there, named scissor trusses and it is checked to be visible. Notice above that there are several layers containing the other roof options we have looked at and that they are not checked to be visible.


By making "components" out of groups of lines drawn the program sees them more as a "thing". It sort of locks that group of lines into being its own thing. I put that thing on its own layer then so it is easy to separate out and edit later, for instance a group of rafters or the floor framing. The component is then not "sticky" when you draw other lines that touch it. For instance if I draw a subfloor over the floor joists the lines don't "merge in the computers mind, those are two distinct objects. I can then switch off the subfloor layer and look, and work on, directly the floor framing.

One more neat thing once you download and get familiar. I can take multiple still screen shots in sketchup while turning on or off layers, animating the plan into a build sequence video. We did this with the school kids last summer when we built a suspension bridge over a creek at the state forest. I animated a sketchup of what we were building and how it was lashed together and had it playing in loop on a laptop sitting on a stump.

[Rys]

Neat! So then I could click on the dormer to save it for further " noodling" ?

[Don_P]

Exactly, you could draw a gable dormer on another layer and pop it in the hole to try it out

[Rys]

Talked to Medeek the other day. Hopefully he'll have a parallel chord truss in his plug-ins soon.
Going to my property today to take some pictures for siting our cabin. This has been a dream years in the making. I am SO excited!

[Don_P]

This is an exported 2d graphic with parallel chord trusses, no engineering, just a concept at this point.


File here;
http://timbertoolbox.com/cp/Rys1.3.skp

there is a crude construction sequence animation in that file. At the top of the drawing you should see "scenes" 1-9. Right click on  the "scene 1" tab and click "play animation". I've turned on layer by layer in the order I would build and taken a "scene" shot, which are strung together in an animation. One by one I've clicked on layers named "foundation", "mudsill", Floor joists", subfloor, walls, etc until the entire frame is built. The ability to show a construction sequence can be very powerful if you think down to the zoom in and show how a detail is built level.

I'm looking at this as a playground, anyone, download, have fun, change it, detail it out, whatever, and post as Rys develops this. Sorry my old system limits me to skp 2016 so save as that version if possible. I think design/build forums where there is a core group of regulars is one way to use what Medeek has been developing, collaborative design.

[Rys]

Thanks Don. 
Will have my computer up and running tomorrow. Can't wait to noodle around with this.
At this point my husband is pretty much waiting on me...   

[Rys]

Just downloaded sketch up. Feel like I'm speaking another language!
Will have to watch many tutorial videos.   

[Don_P]

Good deal.
Open sketchup, top left corner click "file">"Open".
Find the file you downloaded from above called Rys1.3.skp
The model should load. Start playing with the controls, read the above on how to play the nimation, that should help understand how layers are done.  You aren't going to hurt anything, have fun.

If you make changes you want to keep go back up to file>save as and then change the name of the file I would use Rys1.4 next. This preserves the original Rys1.3 file as a restore point on your computer and makes a new file with your most recent changes.

[NathanS]

don't be afraid to invest time in sketchup. I draw out everything I build in it ahead of time, and can even pull measurements as needed.

Start with tutorials, then when you get the basic ideas start googling and looking on youtube for specifics.

There are architects that use it for everything, it is interesting to watch their videos to see how far you could theoretically go with it.