T-111 and rigid foam flashing window install?

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RhodySurpher
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T-111 and rigid foam flashing window install?

#1 Post by RhodySurpher »

I'm just wanting some advice on how to specificaly flash and install a window into a configuration I've never dealt with before. The house is 30 years old and after removing the interior window trim I found that the window had not at all been flashed. I just purchased this house and I'm going to be replacing all the windows. This is the first of many. The wall setup is T-111, rigid foam, fiberglass insulation in the frame, poly as a vapor barrier and then the drywall. My question is more specific on how to flash the window. My best guess is to flash over the foam and install the window that way, but if I caulk around the siding is that going to be enough to keep water from running behind the t-111 or is there another method I'm not seeing. It would seem silly to me to install the window over the t-111 and put molding around it, or would that be a better method. I'm leary of water running down the foam insulation or is this fine as a water barrier? Any help would be greatly appreciated. I want to make sure I do it right before I cause moisture issues inside or rot the siding off of my house. Thanks in advance for any help.

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Windows on Washington
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Re: T-111 and rigid foam flashing window install?

#2 Post by Windows on Washington »

You are going to need to remove the T-111 in order to properly flash the opening in the case of a nailing flange window.

Are you going to be doing the siding at the same time?

RhodySurpher
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Joined: Wed Jan 19, 2011 12:24 am

Re: T-111 and rigid foam flashing window install?

#3 Post by RhodySurpher »

I wasn't planning on it, but as I look at the siding it seems as though it would be a good idea. I've noticed that much of it is starting to fail in a lot of spots due to its age and improper maintenace. Yet another "while I'm at it project." This is our first house and I've already decided that the next one we buy is going to be move in ready. Lol

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Windows on Washington
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Re: T-111 and rigid foam flashing window install?

#4 Post by Windows on Washington »

If you can swing it financially, do them at the same time and do a new construction installation.

RhodySurpher
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Re: T-111 and rigid foam flashing window install?

#5 Post by RhodySurpher »

Thanks for the advice. The more I look at it, the more it looks as if that's the best option. Thinking of doing a side of the house at a time. So, do I flash and install the window directly over the foam board? As well, would it be wise to wrap the house in typar or is this overkill and isthe foam board enough to act as a water barrier?

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Windows on Washington
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Re: T-111 and rigid foam flashing window install?

#6 Post by Windows on Washington »

Typar/Tyvek is so cheap that it is a worthwhile in investment in my opinion. Where is the home located in terms of region of the country. That will have some input on the vapor retarder question.

RhodySurpher
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Re: T-111 and rigid foam flashing window install?

#7 Post by RhodySurpher »

I'm in Wilmington, NC

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Windows on Washington
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Re: T-111 and rigid foam flashing window install?

#8 Post by Windows on Washington »

You are kind of right in the middle from a climate standpoint like we are so you don't even really need one.

The WRB (Tyvek/Typar) will serve as a wind breaker and help air tighten up the home. Well worth the investment.

While you have the siding off, be sure to seal up the bands and any framing members from the outside. Feel free to give me a call to discuss and I will help walk you through the process.

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