Are the gable end walls load bearing? Thoughts on expansion

[dablack]

Ok guys.  It is getting closer to go time.  We haven't ordered the plans but we will be soon. 

I will be building the universal two story.  I know it is expandable length wise and I would like to do so at a later date after building the initial 20x34 building.  (we have four young kids)

My question is, later when I want to extend the house, how will that work?  I get the piers and beams but what about the gable end walls?  Can I just tear those down and the roof be ok? 

thanks
Austin

[PEG688]

Yes, pretty much.  There is a code that calls for a brace wall panel every 25' IIRC , so a wall 90 deg. to the exterior wall that is at least 4 ' long extending into the building.


Like my shop which is 30' wide by 40' long IF I built it today I would have to have one 4' wall panel on each long wall some where near the middle  sheathed on both sides with at leats 7/16" OSB , top to bottom.

This wall resists outward spreading of the bearing walls. My shop is 25 years old has no  interior walls , a truss roof and has survived a  few small earth quakes and every thing mother nature has thrown at it including some winds in the 80 MPH range, some pretty good snow loads , 2 foot-ish loads , etc.

So the short answer to your question is , YES, but there are other factors to be considered , your local building dept. should be able to guide you in the right direction to avoid using a engineer to design your additions. Local codes , wind zones , seismic considerations , etc all could impact your design.     

[dablack]

Ok, so I need some short walls in there to help resist outward spreading of the long walls.......isn't that what the second floor would do?......isn't that what the attic floor/ 2nd floor ceiling joist do? 

I'm starting with a 20x34 and then building it longer at a later date.  I'm sure I will have a couple of walls in there that should be able to do that while I have the one gable wall down. 

thanks
Austin

[PEG688]

Sort of , BUT of course it depends.

Normally even when you extend a house like your considering doing some of the old wall ends up staying , unless the room your extending out of is the biggest room in the house or living room your extending.

  Normally you'd build MOST of the addition BEFORE you removed the end wall , generally your only opening up a passageway , even if it's a wide passage way , but seldom would the entire wall go away.

  BUT if it was your desire to remove the entire wall you more than likely could , but there would be some things to consider when doing so.

My example where generic , there no way to just say "Sure , remove all you want " with the info you provide.

But the IRC prescriptive code requires a 90 degree wall every 25' IIRC , and you need to provide some shear wall sheathing every 25'. They are just attempting to keep the box stiff with the prescriptive code.

  Some one would  need to look at your plans and what you are wanting to do. You can't get a simple yes or no answer to your question with what you have provided.   

But I can with confidence say , MAYBE!    

[dablack]

Peg,

I get what you are saying 100%.  Thanks so much for your help.  I understand now what they are trying to do in the code and I think I'm covered.  I haven't even built the first part yet, never mind the rest but for planning where everything is going to go in the first part, I wanted to make sure that I could build more later. 

I think I'm going to work on my plan a little more so I will have more of a wall where I plan to open up later.

thanks
Austin

[cmsilvay]

When I framed my 14x28 I put headers on each gable end for 6/0 doors and also other header for openings in the side walls for expansion. We had doors in the opening in front going to deck until I made the deck the bedroom. at that point I downsized the opening  to a 2/6  It is a whole bunch easier to have the headers in place and not have to worry about making them after the fact. I would overise the opening it is easier tomake it smaller then larger.
Assoon as snow season ends I plan to go off thesides and back.

[John Raabe]

Planning the existing sidewalls into the layout of the final addition does two things. It gives you the right angle bracing that PEG mentions and uses lumber and materials more economically.

Not that you can't kick out the end walls and just extend the sidewall framing. But everything was cut along that line and at least you want to tie all the plates and framing together with splice plates. You also want a structurally sheathed bracing panel every (min) 25' of the wall and one within 8' of the corner.

[dablack]

Great!  With four kids and maybe more later, plus we home school, we need lots of room.  I'm planning on something around 20 x 64.  A 20 x 34 will be built first and then a 20 x 30.  I will most likely go ahead and build the beams out to the full length so they are ready to go later.  It should only be about a year or two between the first part and the addition.  Once I get a real floor plan program I will lay it all out and show everyone where I'm planning on ending the first house. 

thanks
Austin

[twobritts]

Another idea that hasn't been brought up is that if you are having trusses built, the truss plant can design and build the truss as a structural end truss.  It looks like a combination of a common truss and a gable end truss.