Exactly. The channel just butts up against the door brickmould casing. Need to remove it carefully but not difficult.

these comments don't address re fitting j channel if new door is slightly larger than existing .Anybody got any solutions?

The siding would need to be cutback, no modification of the j-channel except repositioning it after the siding is cut back.

- If the door is measured correctly there will be no issue.

- If for some reason the new brickmold extends past the J, cut back the brickmold. It would be much easier than cutting back the siding and replacing the J (at minuimum the top piece would need to be replaced as it would be too short).

- Not sure if this is what is beign asked, but no, the alumimum trim will not likely be able to be retained/reused.

- Lastly, make sure that the head flashing over the door is in place and properly done to avoid leaking. Based on the J-channel around the light fixture the siding wasn't done by a professional, so who knows what is going on there. While you are on youtube look up how to flash over a window or door.

I see your point HomeSealed. I guess that's why I do not install, lol...................

Order the brickmold "loose" so that you can rip it to width on a table saw before installing. Are you capping the door?

while those answers are viable they don't address the situation of installing j channel which preceeds siding application ,(nailing of j channel is behind siding and cannot be accessed without removing siding or "retoothing it back in .While i thought cutting brick mold was a clever solution it neither addresses a situation where a much larger door is used. In addition cutting molding profiles either interior or exterior smarts of handyman workmanship.

Wut?

@rogerjabrams, I'm sorry, I was addressing the OP, I just noticed that you bumped the thread with a new question. (This is why it would be recommended to start a new thread, but I digress).

Regarding your question, unless the opening is being altered, a door sized to fit the RO will be workable in terms of the trim to J channel interface. Ripping the brickmold to cover any subsequent difference would be indecipherable if done well by a pro and not a handyman. Smaller flat trim could be used as well, among a variety of other ideas that would work and not require removal of the J channel.

If the opening is being altered or you simply insist on pulling the J, you would want to drop the surrounding siding panels to faciliate the removal and reinstallation of that. If the opening is being substanatially widened where the siding is being cut back (but not removed), pros can get creative in reinstalling the J channel. I wouldn't recommend that if you are trying to avoid the handyman look.... although ultimately, the best answer to that question is to order a correctly sized, quality door to avoid that.

I should probably have followed up - appreciated the advice here. I was able to pull it out just as described and it turned out OK. My main problem turned out to be that the existing door, and wall in that area, was over 1" out of plumb from top to bottom - that part was a nightmare.

But I was able to rip some brick molding and had to build a bit of an extension as well since the original jamb and storm and other bits ended up as a thicker wall. I was even able to keep the top drip edge (I still need to clean up the edge to look nicer).

It also turned out the wall studs behind that white trim to the left of the door were rotted at the bottom from water pooling on that step and from chipmunks digging out underneath (no rot from normal weather hitting the door and sill from outside though due to the big overhangs). So I built a form and repoured to fill in the gaps and reform threshold - that part actually came out really well I think.

The original was from 1960 and really hadn't rotted anywhere except for the pooling which I addressed, so I think this fix should at least survive me (50).