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Community and Q&A

Problem with Not to scale Details

homedesign | Posted in GBA Pro Help on

I have started looking at the CAD details concerning how the window interfaces with framing and weather barrier.
I downloaded the head sill and jamb details for windows used with siding.
I put them together in a composite drawing(head/jamb/sill) and noticed that the materials and components do not “line-up”.
I understand that the drawings are “not to scale” probably in order to exagerate the flashing layers.
Maybe what is needed is one drawing that is to scale and another that illustrates an exploded view to illustrate the layering.

I think that if you were to draw the head detail(mentioned above) to scale..then it might reveal a potential design flaw.
It might also be useful to group the head/jamb/sill details in a composite drawing just to verify that the layers do line-up.
One more thought would be to show an outside elevation view of the window and indicate where the drainage weep holes/channels occur. There is a good chance that a painter or future homeowner will do you a favor and block the drainage path.

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  1. GBA Editor
    Steve Baczek | | #1

    The drawings are to scale, any Cadd user with limited knowledge knows that drawings are always drawn to scale. Sometimes, they are not plotted or printed to scale. In this case, they are drawn to scale and also printed to scale. The slight misalignment of materials has to do with taking some artistic license in order to effectively relate the various layers of a window installation. In reality, all materials have a thickness, and they lay right on top of the next layer. If I drew it that way, You would have one muddy line trying to illustrate several materials. It takes some patience and understanding, but the details are drawn correctly to the typical standard of architectural graphics for a window detail.

  2. homedesign | | #2

    Thank you for the feedback...
    I think you miss my point. Of course cad drawings are not usually plotted or viewed at full scale.
    The beauty of cad is that you can Design at full scale and then plot or view at any scale that makes sense.
    I am afraid that the artistic misalignment you speak of might show a drainage path where one may not exist in reality.
    That's why I suggested 2 drawings.. with one drawing at actual scale "non-artistic"... muddy line and all.
    Then imagine "that drop of water" and where will it go or NOT go.
    Unless you provide weep holes or some kind of drainage mesh between the membranes and trim...then It looks to me like the water can only go horizontal towards the jambs...and possibly puddle along the way.

  3. homedesign | | #3

    Steve, Maybe this will help..I noticed the problem on window head details used with siding.
    Examples are 3-00003,3-00006 and 3-00103
    I do not see the problem in details such as 3-00203 or 3-00206

  4. homedesign | | #4

    Steve and Dan,
    I have attempted to draw part of your detail(3-00003) more "to scale" in order to see if it makes sense.
    Am I missing the drainage path?
    Here is your original for reference
    Also...It is not clear to me exactly where you intended the outside continuous bead of sealant to go.

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