Nail Exterior Window Trim Through Nailing Flange?
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I recently installed some new construction windows and am now ready to apply wood trim around them. Is it ok to attach the trim with some of the nails puncturing the flashing tape and nailing flange around the perimeter of the window? It seems to me to be hard to avoid, as the flange is 1.5″ wide, and yet I’m reluctant to put holes in it. What do people typically do? I have looked all over for the answer and found almost nothing. Thanks in advance.
Lee
Replies
Once the flashing tape is on we nail the trim up just like we would anywhere else. We use nothing but PVC trim
Thanks for the reply.
I saw some illustrations in a couple of FHB articles where it appeared as though the carpenter pretty deliberately avoided placing exterior trim nails in an area that would puncture the window nailing fin.
Easy enough to do I suppose, but with this particular project I want to build out the trim in order to conceal j channel. Which would entail a narrow furring strip alongside the j channel. Which would mean nailing through the fin.
I suppose there shouldn't be any space for water to go in there, just take, fin, caulk and solid framing. But still I couldn't help but think about it.
You could apply with (glue and pins) the trim build out to the trim first. Then cut and fasten casing to the wall, keeping those fasteners away from the fins.
Secure your strip to the backside with some TitebondIII and pins. Fasten your casing avoiding the flange. I’d have used self healing membrane around the perimeter beforehand as insurance.
If it worries you, you can place a dab of caulk on the tape in the spot where a nail will be placed. A pencil mark on the window frame will help you remember where the dab is.
Thank you guys for the responses.
Calvin, I think I understand what you are saying. Here is the thing---the nailing fin is 1 1/2" wide. The furring strip is about 2 1/4" wide. The j channel tucks in beside the furring strip. The only space in there for a nail to go without either piercing the nailing flange or the j channel is the 3/4" between the flange and the j channel. That's the only area to nail not only the furring strip without piercing the nailing flange, but also the final layer of trim.
The flashing tape I used is 3M All Weather Flashing tape. I don't think it is self-healing. Just insanely sticky. Under that there is the flange, and then a really heavy bead of caulk under the flange.
Dan, I thought of something similar to what you propose. I thought of driving a screw, backing it out, and then driving it in again with some caulk in the threads.