[Greenbuilding] interior storm windows: mounting against beveled jambs & spacing

[Topher]

On 11/1/2014 11:44 AM, Reuben Deumling wrote:
> Topher,
> I have a bunch of single pane windows with beveled jambs (30deg) I'd like
> to add interior 'storm' windows to, using your approach.
> http://www.greenfret.com/storms.html  How much space would you leave
> between the two windows? From what I know about how air moves, my guess
> would be 'as little as possible.'

Somewhere around 1/2" to 3/4" is best.  The goal is to add two still air
spaces, one inside the interior storm, and one between the interior
storm and the existing window.  What this often mean is pushing the
storm right up against the window sash.  That is probably easiest given
a beveled jam.

> Secondly, I'm trying to think of a way to hold them in place. Attaching
> four of those studs with wood screw threads on one end, and machine threads
> on the other to the edge of the sash, and drilling equivalent holes through
> the storm window frame I figured I could use wingnuts to snug the storm
> against the beveled jamb. Thermally elegant, but it leaves four studs
> jutting into the living space during the rest of the year, which isn't
> great. Have you encountered this, or have suggestions?

I have use, smallish chunks of wood, bevel-cut, and screwed into the
jam.  Or screen holders.  Or a track above, and something screwed into
the stool.  Good luck, and please let me know what you come up with.

Thank you kindly,

Topher

-- 
Topher Belknap
Green Fret Consulting
Kermit didn't know the half of it...
http://www.GreenFret.com/
topher at greenfret.com