Extending Wall to Roof Problems

[TomR]

I am new to TFP.  I am trying to design a cape type house, where the roof is on the 1st floor location and the second floor is enclosed by the roof.  The 2nd floor interior walls are knee walls to the roofs ceiling.  Being that the walls on the 2nd floor are on the 2nd location and the roof is on the 1st location, the walls do not recognize the extend to roof, thus they shoot through the roof.  What is the trick for them to recognize the height of the roof (to automatically determine the knee wall height)?
Similarly, the roof is gable, the 1st floor location exterior wall will extend past the 2nd floor to the gable and nicely taper to the 12/12 pitch.  But the extended wall will not take a window.  With the extend to roof turned off, inserting an exterior wall on the 2nd floor, how do you get it to recognize the 12/12 pitch, rather than sticking out the sides of the roof.  Or how do you insert a window on the extended portion of the wall.

[Allan Chesney]

Hi Tom,
Welcome to the Forum.

I am not a builder and from Australia so I am not familiar with some of the terms you have used as I have not heard them here(eg Cape and Knee walls) but the problem sounds like the wall height settings of the two Locations. You need to set both of them to the VERTICAL portion of the wall.  Normally the roof would be inserted on the second floor not the first and if there is not any vertical portion of the second floor (except the gable ends of course) then they should be set to just 1mm or a fraction of an inch.  They will still accept windows and doors as long as they are set to extend to the roof. 

I am not sure of your house design but if the roof comes down below the second floor level, ie there is a sloping section of wall in the ground floor portion also (as in my image - I have highlighted the second floor so you can see where it sits), then the ground floor walls would again be set to the vertical portion (eg 6ft or 1800mm in my example) and a roof inserted here also.  It will automatically cut out the upper floor roof but you may have to do some fine adjustments to get them to align.
 
Or... You could use the first floor roof but insert a second floor one also (so that second floor walls will extend to the second floor roof and then turn the second floor roof off in the display filter.  You would also have to force the first floor roof not to cut out the second floor roof.  In this case insert the window in the ground floor wall and right click Elevate it to the upper floor height. Set the gable end walls on the upper floor to NOT extend to the roof (or they will fill in the window) and set the ceilings to Cathedral. Make sure the second floor interior walls are set to extend (or they will be 1mm high!)

I hope that some of the above answers your questions - if not just ask again where it is not clear.

Allan

[TomR]

Thanks Allan, I now learned the use of the extend command.  I placed the roof on the ground floor because I could not figure out how to get it to set on the second floor.  It always adds 8 foot walls on the non-gable sides.  I want the rafter birds mouth to sit on a sill plate on the second floor and the gable end walls to extend to the 12/12 pitch peak.
In the roof properties, support and details tab, I tried to set the "support height"-"a" to 0, or 1", or 2", yet the roof appears sitting on a full second story height walls.

[TomR]

Allan, I figured it out.  I started a new drawing and did just what I last described to set the roof on a second floor sill plate.  The sill plate wall framing is set to zero, the extend to roof option on.  It worked while the roof support height was set at 1", only this time it stayed at the 1" setting.  I had entered 1/2" in the support height, but it decided to keep it at 1".  Ok with me at this point.
Only the 50th time I tried this.

[Allan Chesney]

Hi Tom ,

By default the Support Height is the same as the wall height as set for that location, so normally should not need to be changed except to raise the roof to achieve some special effect.

Setting fractions of an inch will be affected by the Settings / Program Settings.

Good to hear you are getting there.

Allan