Is anyone familiar with the reason for a sub-sill? I have been helping a friend replace the windows in a moutain cabin that was built in 1932. The original construction is representative of the time and remote location; rough studs (2-1/2″ x 4-1/2″) on a rubble foundation with a casual approach to framing and details. The windows are wood frames and sash with a mixture of fixed glass and casements. All of the windows in this group of 10 cabins were framed with a sub-sill below the window frame; The sill of the rough opening is a 2-1/2″ x 6-1/2″ set to slope to the outside at the angle of the window sill and extending out beyond the exterior finish . The sill of the window frame is a 1x and is sloped to match and sits on top of the sub-sill. This detail may be more weather tight than a flat rough sill, especially if you do not have access to much in the way of flashing materials. I have worked on some baloon framed houses from the late 1800’s and early 1900’s in costal California and they have not had this detail. Was this a common approach or perhaps just the way the original carpenter liked to work?
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I've not seen this detail before. I see a lot of earlier houses with no rough sill at all...the cripple studs just but into the underside of the finish sill, but never one such as you describe.
Steve
Steve, glad you could follow that!>G<
Sounds like one mans idea of a good idea.
There were a lot of unique things done in the thirties. Recall that it was a depression so people did any job they could, and the folks paying for the work hired as cheaply as possible, so not everyone followed standard practices.
The 1970's is another period of some uniqueness in the US, because money was tight, and there was a fixation on developing new alternatives for energy conservation. since then, we've learned a lot more about things that sounded like good ideas then, but just don't work.
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But how could it not work... at least from a functionality standpoint? Water won't run uphill at least theoretically. I can understand it is a bad idea from the standpoint of time consumed and difficulty to duplicate but my initial reaction is that it would have to work just might not have been workable.
Something like this from the 1950s. The concrete wall has a slope on it to the outside and the rough framing for the window is built on top of it. Looks like they just put some more concrete on later to make it level. Not sure what the deal is with that. In anycase the sill plate on this concrete wall rotted out within the 55 years it was installed. The detail in the picture probably made water stay within that area instead of draining out. If there had been weep holes or something in the diagonal fill maybe I could see this helping keep the water away from the sill.
I don't really see anything wrong with it, just different than normal, and commenting on why possibly.
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Isn't this roughly the same thing as putting a piece of beveled siding on top of the sill, as part of the flashing scheme, which some people here do?