Repairing paint damage on roof fascia board

[Oro_O]

Advice on repainting this water damage on a fascia board. This paint peels. It was bad the first time ~10 years ago (at 15 y.o.). In high, dry summer I sanded everything back, let it dry out fully and repainted. it lasted ~8 years. Anything I can do to stop it happening again, or it's just going to happen because of the joint there. If you look closely there is a joint at the point it starts.

This is the only spot on the house it hapens.

 

[Cdn17Sport6MT]

I could be wrong here with terminology, but I believe that trim is "fascia" where you mount a gutter on it (i.e. at the base of a roof pitch) but it's called a barge board where it's on a gable end (like yours).

Re the paint, I'm pretty sure the joint causes the issue, but Others, would some shellac better seal the wood as a primer?? Maybe Zinser's BullsEye?

 

[doitmyself]

The problem is that there is movement at that butt joint and anything there is going to crack. Shellac is a bit brittle and I think it might crack even faster than other penetrating primers. It does look like the butt joint was cut at an angle (see bottom) to help water run the correct way. But still, there is movement there.

I cannot think of a mechanical fix for that joint - one that eliminates the effect of expansion and contraction, like flashing takes care of. I was wondering if it might be better to actually open up the joint bigger and fill it with high quality paintable caulk. Even that will crack if the movement is too big. I doubt that a thin fiberglass cloth/resin joint cover would last. A vinyl or aluminum fascia cover would not match the character of the house. I'm stumped. Maybe just plan on cleaning and painting every 5 years??

 

[spasm3]

The problem is that there is movement at that butt joint and anything there is going to crack. Shellac is a bit brittle and I think it might crack even faster than other penetrating primers. It does look like the butt joint was cut at an angle (see bottom) to help water run the correct way. But still, there is movement there.

I cannot think of a mechanical fix for that joint - one that eliminates the effect of expansion and contraction, like flashing takes care of. I was wondering if it might be better to actually open up the joint bigger and fill it with high quality paintable caulk. Even that will crack if the movement is too big. I doubt that a thin fiberglass cloth/resin joint cover would last. A vinyl or aluminum fascia cover would not match the character of the house. I'm stumped. Maybe just plan on cleaning and painting every 5 years??

I agree, and no way to seal it from the back side without doing that.

 

[PimTac]

Water is getting into that seam. My guess is that the seam ends are not painted. The water swells the wood and there ya go.

Scrape it down and seal that seam, front and back and bottom. Repaint.

 

[Oro_O]

Water is getting into that seam. My guess is that the seam ends are not painted. The water swells the wood and there ya go.

Scrape it down and seal that seam, front and back and bottom. Repaint.

OK, this matches what I figured (and others said above). The joint is letting water in and that causes the swelling and paint failure. So what you all say makes me think of this:

Idea:

1) scrape/wheel it off clean.
2) "V" the joint a bit to make a channel.
3) Fill it w/epoxy to seal it
4) Sand everything smooth and paint.

Does that sound like a reasonable plan? It won't seal the joint entirely if I don't remove the board, but it might reduce the water intrusion 75%, which might give the paint a fighting chance.

If it were metal, I would know the best primer, but what's good for this? Anything special like Zinsser's (I think I have some anyway).

 

[nomas]

Did you prime it prior to painting ?

 

[doitmyself]

That's the idea I initially thought of with "open up the joint a bit".

If there is movement, either sideways or lengthway (wood expands/contracts quite a bit), I think epoxy will also crack. Would a flexible caulk fare better?? Who knows. They cover wood strip canoes with fiberglass cloth/resin (Google it) - my second idea is to sand down to bare wood and bridge the butt joint with a thin layer of fiberglass cloth/resin, then prime and paint. Still, expansion/contraction might destroy it.

Also, its best to prime bare wood before caulking (what I was taught). I would use thinned down oil base primer for penetration and breathability, covered by acrylic paint.

Also, is there access on that back side that you can glue/screw a gusset there to stiffen the joint without introducing another water collection point?

 

[PimTac]

OK, this matches what I figured (and others said above). The joint is letting water in and that causes the swelling and paint failure. So what you all say makes me think of this:

Idea:

1) scrape/wheel it off clean.
2) "V" the joint a bit to make a channel.
3) Fill it w/epoxy to seal it
4) Sand everything smooth and paint.

Does that sound like a reasonable plan? It won't seal the joint entirely if I don't remove the board, but it might reduce the water intrusion 75%, which might give the paint a fighting chance.

If it were metal, I would know the best primer, but what's good for this? Anything special like Zinsser's (I think I have some anyway).

The Zinssers should work. I wonder if creating a V will help. The water and moisture can access from any side of that seam, even the top. They cut that joint on a angle too

Maybe a double coat of the Zinssers as a base the finish with your regular color?

Can you lift the roofing on top to prime the top edge?

 

[Oro_O]

Did you prime it prior to painting ?

I want to think I used the Zinsser on it and that was it - but I just can't recall as it's been enough years. I just can't recall perfectly. I know I machine sanded it really, really well and let it dry before painting.

Can you lift the roofing on top to prime the top edge?

Yes, I think the shingles are just laying on it at that point.

 

[PimTac]

That's the idea I initially thought of with "open up the joint a bit".
View attachment 109258
If there is movement, either sideways or lengthway (wood expands/contracts quite a bit), I think epoxy will also crack. Would a flexible caulk fare better?? Who knows. They cover wood strip canoes with fiberglass cloth/resin - my second idea is to sand down to bare wood and bridge the butt joint with a thin layer of fiberglass cloth/resin, then prime and paint. Still, expansion/contraction might destroy it.

Also, its best to prime bare wood before caulking (what I was taught). I would use thinned down oil base primer for penetration and breathability, covered by acrylic paint.

Normally this would work but the person that installed that cut the seam edges at 45° angles.

 

[PimTac]

I want to think I used the Zinsser on it and that was it - but I just can't recall as it's been enough years. I just can't recall perfectly. I know I machine sanded it really, really well and let it dry before painting.

Did you prime the cut edges?

 

[Oro_O]

Did you prime the cut edges?

I didn't take the board out when I sanded and repainted, so whatever paint is on the edges was put on 25 years ago when it was built.

I didn't get agressive with paint on the back side or under the shingles on the joint. The water (majority) may be entering there as it runs down the shingle line. The prevailing weather is from the other side (peak of the roof/back side of house). This is roughly the east side so it gets sun all summer, and the rain and wind come from the other direction the rest of the time.

 

[Racer4]

Scrap the big stuff, sand, I find oil based primer works best.

 

[Nukeman7]

You will need to use this high solid primer on the bare wood before applying the paint to keep it from peeling:

PPG GRIPPER Primer

 

[slo town]

OK, this matches what I figured (and others said above). The joint is letting water in and that causes the swelling and paint failure. So what you all say makes me think of this:

Idea:

1) scrape/wheel it off clean.
2) "V" the joint a bit to make a channel.
3) Fill it w/epoxy to seal it
4) Sand everything smooth and paint.

Does that sound like a reasonable plan? It won't seal the joint entirely if I don't remove the board, but it might reduce the water intrusion 75%, which might give the paint a fighting chance.

If it were metal, I would know the best primer, but what's good for this? Anything special like Zinsser's (I think I have some anyway).

I painted my way through middle school, high school, and parts of college (a large apartment complex our neighbor owned).

I like your plan other than using epoxy. I'd use a paintable silicone/latex caulk instead. Also too, prime the area before caulking and painting. I've never been a fan of Zinser products but no BD if you use it. And from the condition of other woodwork it looks like this is an exposure that gets more sun, rain, wind, whatever. Paint the other bits too before the paint peels there.

Regardless, I don't think a permanent repair is possible. My suggestion is to keep and eye on it and repair it at the first sign of peeling. Maybe even do a preventative thing, painting that 18 inch long section every year or two. That would take all of 10 minutes. This would help you avoid scraping and sanding, which is by far the biggest PITA in jobs like these.

Scott