question about extending the width of 20x34 Universal cottage

Started by ironhead, June 11, 2009, 09:45:04 PM

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ironhead

Hi: Can anyone tell me what changes I need to make to the rafters and joists for a 24 foot width to the 20 x 34 Universal cottage.
I also want to increase the length, but that is easy. I think making it wider is more complicated. I also want to have 9 foot walls. Any Help appreciated. This site is so great and inspiring.



John Raabe

You will need to use the internal beam design for the floor joists (not the full width span design). See Sht. 10 of the plans and use the wood joist framing plan. Then you can resize the floor joists with the chart above (here is a tutorial on how to use it - http://www.planhelp.com/public/98.cfm). I would go to 2x10 joists with the same spec as the 20' design.

Now, the girders are sized for the specific spans and the loads from the floors. You have now increased that load and will need to resize the beams. Here you may need some help from a short consultation with a local engineer or home designer. But, before you do that make sure you know how you will change the wider floor plan layout as you may want to move the bearing posts and thus change the beam spans. So get the new layout worked out first. Using a template plan can help work this plan up and give you a scaled printout you can paste back into your plans. See http://www.planhelp.com/public/92.cfm.

The attic and roof framing options on Sht. 4 will likely work for the wider house but heavy snow or wind loads could require up sizing the rafters and attic joists. Check this at the same time when you have your consult. If you choose one of the truss roof options then the new engineering is done by the truss company.
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ironhead

Hello John: This is very helpful information.  I am sure I will be back for more questions as I progress. Just in the planning stages now and ordered my material list last night. Thank you for your time on this.