Window leaking when it rains. What type of caulk and how do I apply it?
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Window leaking when it rains. What type of caulk and how do I apply it?
We bought a new home and have a large window above our bed leaking when it rains. I need to caulk around it I suspect but have never done this. Figure it might be a good time do caulk around all windows. Home was built in '99 and the home inspector suggested caulking. I nodded, like men do, but sad to say I really didn't understand what to do about it. A caulking gun I guess for a job this size. But what kind of caulk should I use and how do I apply it? Thanks for any suggestion.
The big arched window is the one that is leaking.
The big arched window is the one that is leaking.

#2
It depends WHERE it is leaking. You say it's the arched window that is leaking, but is the leak at the top of the arch? near the bottom of the glass? Dripping from the top of the windows that are immediately BELOW the arch, or what?
Where is the water showing up? Middle of the arch, corners?
As for the caulk, you'd probably want to select a color that blends well with the color of the exterior window frame and the siding. Bronze/Brown/Terratone, something of that nature. Can't tell from the pics what color your windows are, it's too far away.
Where is the water showing up? Middle of the arch, corners?
As for the caulk, you'd probably want to select a color that blends well with the color of the exterior window frame and the siding. Bronze/Brown/Terratone, something of that nature. Can't tell from the pics what color your windows are, it's too far away.
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The leak is on the top of the arch, then runs down, pools on the flat ledge (inside house) at bottom of window, then runs down the trim, then pools at a ledge where the lower windows (rectangle) are. Pretty good amount of water when the wind blows the rain towards this side of the house. Below is a pic of the house stain, which we are getting redone in the coming weeks as well. So the caulk is color coordinated to the house color? Good to know, I assumed it was some kind of clear caulking. Thanks for the reply.
The pic below shows our kitchen window, which is identical to the leaky bedroom window...
The pic below shows our kitchen window, which is identical to the leaky bedroom window...

#4
The thing that makes me wonder about your leak is that your arch window, (and those below it) likely have nailing flanges. If water leaks in around the window, the nailing flange "should" be directing water down to the lower parts of the window before the leak shows up. Since water is coming in at the top it seems to indicate that water is either jumping OVER the nailing flange, or the leak is originating much higher than the window (roof or soffit)
If you have a piece of trim covering the nailing flange, the perimeter of this trim might need to be caulked to the clapboard siding.
But if there is no exterior trim around the window, water "could" be running along the top edge of a clapboard, then running down behind the nailing flange. In that case, you'd caulk the clapboard siding to the window.
If you get up there on a ladder and don't find any apparent "gap" that needs to be caulked... then it would make me wonder about your ridge venting on the peak of the roof. It's often possible for wind blown rain to enter the roof/wall where the ridge vent ends. You'd probably need to remove a couple pieces of siding way up in the peak and see if there is any evidence of wetness on top of or behind your housewrap/building paper.
As far as the caulk color is concerned, you "can" use clear but clear caulk isn't invisible. It's often best to match one color or the other- either the siding or the window. In your case, it might be best to match the window since your siding appears to be stained, and its color will likely change over the years as it either weathers or as you restain it.
Regarding the type of caulk, the only advice I'd give is to avoid anything silicone, or anything that says "painter's caulk" which usually doesn't last very long. Other than that, you probably can't go wrong with any type of caulk that says it's for siding, whether it be latex or urethane.
If you have a piece of trim covering the nailing flange, the perimeter of this trim might need to be caulked to the clapboard siding.
But if there is no exterior trim around the window, water "could" be running along the top edge of a clapboard, then running down behind the nailing flange. In that case, you'd caulk the clapboard siding to the window.
If you get up there on a ladder and don't find any apparent "gap" that needs to be caulked... then it would make me wonder about your ridge venting on the peak of the roof. It's often possible for wind blown rain to enter the roof/wall where the ridge vent ends. You'd probably need to remove a couple pieces of siding way up in the peak and see if there is any evidence of wetness on top of or behind your housewrap/building paper.
As far as the caulk color is concerned, you "can" use clear but clear caulk isn't invisible. It's often best to match one color or the other- either the siding or the window. In your case, it might be best to match the window since your siding appears to be stained, and its color will likely change over the years as it either weathers or as you restain it.
Regarding the type of caulk, the only advice I'd give is to avoid anything silicone, or anything that says "painter's caulk" which usually doesn't last very long. Other than that, you probably can't go wrong with any type of caulk that says it's for siding, whether it be latex or urethane.
#5
To add, elastomeric caulk would be a good choice, since the wood will swell and contract with the seasons. It can be found at most lumber yards, hardware stores, and big boxes. Elastomeric comes in colors, is paintable, but will not crack or pull loose as was mentioned.
#6
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A clear siliconized acrylic latex caulk might be the most user friendly. It goes on milky but dries clear so a not so perfect caulk job won't be as obvious 
With any latex caulk, keeping a wet rag handy will both help you to smooth out the caulk you applied, wipe away any excess and keep your fingers clean

With any latex caulk, keeping a wet rag handy will both help you to smooth out the caulk you applied, wipe away any excess and keep your fingers clean

#7
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A properly installed window should never ever need to be caulked once it's installed. The only caulking that should have been used is behind the nailing fin before it was installed.
I'd guess that someone left out the flexable J moulding that was suppost to come with the window that gets installed once the window goes in. Without it water can leak in behind the siding.
I'd guess that someone left out the flexable J moulding that was suppost to come with the window that gets installed once the window goes in. Without it water can leak in behind the siding.
#8
If water gets behind the housewrap, then all bets are off. Even when the head is taped directly to the sheathing, that won't stop every leak that occurs above a window (such as ice dams or a leaking ridge vent).
At any rate, the OP seems to have disappeared.
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Still here
On iPhone no Internet at home. Getting hooked up next week
Wife and I are travel nurses and were in Alaska. Just flew in yesterday. I appreciate the input. Buying ladder and some caulk soon
Dan

On iPhone no Internet at home. Getting hooked up next week
Wife and I are travel nurses and were in Alaska. Just flew in yesterday. I appreciate the input. Buying ladder and some caulk soon
Dan