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Does a 6-12 roofline mate up well with 12-12 roofline?

Cottageroof | Posted in General Questions on

I’ve got a 2 story 26′ by 32′ cottage with 12-12 pitch.

I would like to add a 12′ by 16′ screened in three season to the gable side on the North side.

The Contractor recommends matching the cottage roof pitch (12-12)…

However, in the effort to have generous overhangs and to not increase the building shadow “footprint” on the North side of the deck (next to screened in porch) I am considering giving the screened in portion a 6-12 pitch… in my thinking this reduces the height of the 3-season and therefore does not increase the shadow footprint already thrown by the main building.

So my question is, if I’m looking at a 12-12 sloped roof (pitch side) of a 2 story building to which I’ve mated a one story 6-12 sloped roof of a screened three season, would that look OK?

Is there any common wisdom on two different pitched rooflines when mated at the gable end?

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  1. GBA Editor
    Martin Holladay | | #1

    If I'm designing an addition, I try to have the roof slope of the addition match the roof slope of the main house. This concept is widely ignored, however (and it's not always possible to achieve). Some additions that violate my rule look OK -- others look really terrible.

    This is a judgment call. Draw up both options and look at the sketches. It's your house, so you get to decide.

  2. Cottageroof | | #2

    Thanks Martin !

    Given that I'll be looking at it a long time (Lord willing :-) ) I will match the two pitches.

    I did draw it (as opposed to trying to visualise it in my head) and it did help.... the 6/12 drawing gave the impression of a "squashed" or "overpowered" addition. The 12/12 drawing does look more proportionally pleasing in terms of end result. I appreciate the suggestion!

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