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Simple idea for creating flashing pans

Modern windows are exceptionally simple to install, highly resistant to weather, rot, mold, the effect of sun and changes in temperature.

However, a key to a long-lasting window is a quality installation. One-third of all warranty claims fielded by the Atlantic Home Warranty organization are related to the improper installation of windows.

A key component is a flashing pan. We’ve talked about this before: the requirement for a waterproof system at the bottom of the window that extends into the building framework, in case water penetrates there.

That flashing pan, by Code, has to have a slope of no less than six per cent to the outside. The intent being is that if water accumulates under the window – whether driven by rain or because of a fault in the window itself – it can drain to the outside.

One of our inspectors saw a nifty way to achieve this requirement at a jobsite today: the contractor had on hand a stock of cedar cladding, which like cedar shakes have an inherent slope to them.

Sloped wood for a flashing pan
Although a little difficult to see in this image, this section of cedar slopes outwards. By laying this down, and then installing flashing tape, the contractor has easily and quickly built a flashing pan as required by Code.

By simply installing these pieces of wood so they slope to the outside, then using a flashing tape to provide the flashing pan, the contractor has quickly and simply created a sloping bed sufficient to meet or exceed Code.