Blueskin on Windows: Why Is It Important

Without a doubt, one of the most common areas of water intrusion on any building is around window openings. Improperly installed windows will allow water to leak in behind claddings and onto framing members, and when mould or rot appears, the cladding is often inaccurately blamed. The fact is that improperly installed windows will cause leakage and water entrapment on the framing of any building, regardless of the cladding.

It has been a point of contention on many projects – commercial and residential – as to who’s responsibility the proper sealing of framing around the windows is. The framers point to the window installers, who point to the cladding guys, who point back at the framing guys, and eventually someone is selected by the general contractor to do the work. A good portion of the time EIFS contractors I have worked with have been the ones selected. In reality, they are probably the most qualified to do this job. There’s an issue with this, but it’s not the topic of this article.

When I ask a home owner – who is replacing windows as well as retrofitting with EIFS – if the window installers have specified blueskin as part of their installation process, I typically get a blank stare. They don’t understand that 20 years ago, most builders had no clue that the window frame needed to be sealed. Some builders today still don’t. But when you’re taking the old windows out and replacing them with energy efficient windows, you have the perfect opportunity to protect your walls from water intrusion, which may lead to mould, which can cost tens of thousands of dollars in repairs. It’s actually something the home owners can do themselves if the window installers refuse or claim it’s “unnecessary”.

So here’s your quick rundown of the blueskin product.

This is what blueskin looks like when you buy it in a store:

Blueskin purchased from hardware store

Blueskin purchased from hardware store

Here’s the primer for the product, which you roll-on just like paint, before applying the blueskin:

Blue Skin Primer

Blue Skin Primer

Blueskin is a “peel and stick” product, meaning you peel the material from the backing and stick it on to your framing, like this:

Peel the blueskin from the backing

Peel the blueskin from the backing

And this is what blueskin looks like installed:

BlueSkin with primer around window opening

BlueSkin with primer around window opening

It’s somewhat reminiscent of wall papering, using much smaller pieces. You want to start in the middle and flatten it outwards, so as to avoid air pockets. Seams need to be overlapped 2″ (typically at corners) and you want to extend it down the face of the substrate (dens-glass-gold in this case, the yellow material) about 4″. The EIFS contractor will then come along, and overlap his weather barrier with the blueskin, entirely sealing your windows from water.

An alternative to BlueSkin (by Bakor corp.) is Soprema’s Sopraseal 1100T Рwhich is essentially the same product. Your local hardware store should carry one or the other.

It is not an expensive step to add, or very complicated, to ensure your project is properly completed. If you’re replacing your windows – make Mike Holmes proud – do it right.

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  1. Chris

     /  April 16, 2010

    I agree with general concept around the windows MUST be prepared before applying styrofoam. I disagree the BLUE SKIN is the best product on the market for that. They are at least 5 different tapes you can choose from for that purpose, some of them much better from blue skin. BLUESKIN has a shiny surface – therefore does not grab and hold any plaster on top . So around windows you must use screws to firmly secure foam not to flap under the blue skin-(4-5 inches or so around the window). I try to avoid always screws I DO NOT RECOMMEND the blueskin as a top quality product for this purpose.

  2. Admin

     /  April 24, 2010

    Thanks for chiming in Chris. There are certainly other products that can serve the same purpose, such as Soprema’s Sopraseal. Actually, I believe that a lot of EIFS manufacturers have their own product for this purpose as well.

    Blueskin is simply the most common, and would be better to have than nothing at all. What do you typically use?

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