Vinyl siding leaking at corners

Old 04-02-05, 12:58 AM
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Vinyl siding leaking at corners

I have recently installed vinyl siding on an old addition of my house. The addition is above-ground on a concrete slab. The slab is not level.

Two of the corners are showing leaks at the base of the siding underneath the footers. The inside walls are totally exposed (studs, plywood visible; tyvek wrap in front is not visible but is there), and I can see that no water is coming in from above...the leak is definitely from underneath.

The lower channels and corners meet the perimeter of the concrete slab and are caulked all the way around.

What can I do to prevent the persistent leaking at the two corners? I'm at a loss...

Old 04-02-05, 05:32 AM
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>>The lower channels and corners meet the perimeter of the concrete slab and are caulked all the way around.

This makes me think that perhaps you are damming up water that needs to get out. On houses where a slab protrudes past the sheathing, or where they've poured cement around the house (as a sidewalk or similar) you don't caulk vinyl siding to a slab, you flash the wall and caulk the flashing to the slab BEFORE you put up the siding, then the tyvek goes over this flashing. Since water can get behind vinyl siding at any number of places, it has to be allowed to escape at the bottom.

Does your siding come right down to the cement (sidewalk or similar) on the outside?
By "lower channel" do you mean that your siding starts in a j-channel or finish trim? If there is cement outside, is it higher than the sill plate and floor inside?
Is there an overhang (soffit) that would prevent water from running in the top of the siding?
If you have gutters, are they plugged up?
If there are vertical seams in the tyvek at the corners or horizontal laps, has the tyvek been overlapped and flash taped?
Does your tyvek overlap the sill plate? (the part of the wall the bottom end of the studs are nailed to)
Does your siding overlap the sill plate?
Are there any penetrations in the siding near the leaks? (Dryer vents, windows, outlets, light fixtures, gas pipes?)

just a few things to think about.

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