End Damming Over Doors and Windows

Capillary action is great for trees and plants, because it allows water to flow from the roots all the way up to the leaves. However, water’s ability to literally pull itself up by the bootstraps can be a pain in the construction industry. End damming aims to prevent this happening around the tops of windows and doors.


Sealing the Joints Between Doors, Windows, and Walls


No door or window is ever a 100% perfect fit in a wall opening. Construction is not an exact science, and besides we need a bit of leeway to position a door or window correctly. The result is a crack that’s wide enough for the wind to whistle through, or capillary action to worm its way inside.

Traditional sealing involves caulking this opening, and so ‘stopping the leak at the source’. Window and door installers should then fit aluminum flashing over, although not all do so satisfactorily.

Caulking can fail after repeated expansion and contraction, especially if the opening faces blazing summer sunlight or prevailing gales in winter. When caulking cracks, its primary protection can no longer withstand the capillary action of water.


End Damming Works Around This Problem


The true source of a leak then becomes water running down the wall, and looking for the tiniest opening to capitalise on. End damming is like a separate eavestrough, in that it catches the water, and drains it away.

The joins around the end dam vanish seamlessly when we fit the siding over to finish off the job. That should mean no more water leaks, because you have triple protection from your caulking, flashing and eaves dam.


A Bit of Extra Care Up Front Works Wonders


At Valiant Exteriors we believe if a job is worth doing, it is worth doing well. Sure, end damming adds a little to the cost of door and window installation. However, water penetration could cause damage costing considerably more to repair.

We are proud of our work. We want to sleep peacefully at night knowing the windows and doors we install are perfectly watertight. You are more than welcome to call (403)829-1661 or write to us at this address if you need advice about doors and windows, or any other aspect of the exterior of your home.

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