Thread: Stains on aluminum soffit?

Multiple stains on aluminum soffit covering with no signs of leakage from the attic or looking up through the perforations. All first course of shingles and starter strip in good shape and properly sealed. Three tab shingles are eight years old and in great condition. The drip edge and fascia are also fine. No gutters; it was raining and droplets were forming on the bottom lip of the fascia covering and may be wicking up under the soffit (not sure). Any thoughts on this, thanks.

Originally Posted by mark petty

Multiple stains on aluminum soffit covering with no signs of leakage from the attic or looking up through the perforations. All first course of shingles and starter strip in good shape and properly sealed. Three tab shingles are eight years old and in great condition. The drip edge and fascia are also fine. No gutters; it was raining and droplets were forming on the bottom lip of the fascia covering and may be wicking up under the soffit (not sure). Any thoughts on this, thanks.

Also; only found on right side of the home which faces southeast.

Is that eave visible from the attic, even from afar?

Dom.

Bathroom vents dumping into the soffit area?

Originally Posted by mark petty

... it was raining and droplets were forming on the bottom lip of the fascia covering ..

Mark,

"fascia covering"?

Is the fascia covered with aluminun?

From the mitered fascia joint it looked like it was just wood fascia?

If the fascia is wrapped, that could be caused by the fact that aluminum fascia is basically a "J" shape with the long leg of the "J" slipped up behind the drip edge - any water getting to the backside of the drip edge is trapped behind the fascia covering, runs down the backside of the aluminum to the bottom of the "J", in under the fascia, and then up and out the back of the short leg of the "J", which typically shows up on the soffit like that.

It could also be from a leak from above and dripping down onto the soffit.

As previously suggested, could you see that area from the attic? It's kind of long (covers a long area) to be from a bathroom exhaust fan, but there could be several up there. Maybe insulation laying out over the soffit?

Any lawn irrigation sprinklers along that area which are misdirected and hitting the soffit?

Originally Posted by Jerry Peck

Mark,

"fascia covering"?

Is the fascia covered with aluminun?

From the mitered fascia joint it looked like it was just wood fascia?

If the fascia is wrapped, that could be caused by the fact that aluminum fascia is basically a "J" shape with the long leg of the "J" slipped up behind the drip edge - any water getting to the backside of the drip edge is trapped behind the fascia covering, runs down the backside of the aluminum to the bottom of the "J", in under the fascia, and then up and out the back of the short leg of the "J", which typically shows up on the soffit like that.

It could also be from a leak from above and dripping down onto the soffit.

As previously suggested, could you see that area from the attic? It's kind of long (covers a long area) to be from a bathroom exhaust fan, but there could be several up there. Maybe insulation laying out over the soffit?

Any lawn irrigation sprinklers along that area which are misdirected and hitting the soffit?

I could see the wood sub fascia from the attic, not a great view but through the baffles and no signs of blackened wood.
I also shined a flashlight up through the perforations from outside, again, not a great view but no signs of blackened roof sheathing.
All baths are properly vented up through bath vent shrouds.
Soffit and fascia are aluminum.
Singles are all well sealed to drip edge.
No sprinklers.
The only thing I can think of is wicking or capillary action.
Otherwise I'm baffled.

On the inside of the fascia, how far up from the bottom of the fascia was the soffit?

The rain will run down the front side of the fascia, loop around the bottom of the fascia, and, if the soffit is not high enough up, that water will wash back onto the soffit, wicking back as you referred to it. That is a possibility - they may not have installed the soffit high enough along that side to create the necessary rain drip edge to allow the rain to break its surface adhesion to the fascia surface and allow it to drip free.

Originally Posted by Jerry Peck

On the inside of the fascia, how far up from the bottom of the fascia was the soffit?

The rain will run down the front side of the fascia, loop around the bottom of the fascia, and, if the soffit is not high enough up, that water will wash back onto the soffit, wicking back as you referred to it. That is a possibility - they may not have installed the soffit high enough along that side to create the necessary rain drip edge to allow the rain to break its surface adhesion to the fascia surface and allow it to drip free.

Jerry, that's the only conclusion that I could come up with. It started to rain pretty good later and I could see heavy droplets beading up on that short bottom J of the fascia covering but couldn't actually see it being drawn up. Many times I've seen these types of stains in the past but at a smaller scale. Most times the roof was aged and tabs no longer sealed to the drip edge and I thought what was happening was what you mentioned earlier about water running down the backside of the drip edge. Thanks everyone for the help

Could it possibly be old stains from the old leaky roof? They may have replaced some sheathing.
I know Florida gets wind and rain, but that seems extreme for wicking. If it is that, the stained soffits would be dripping wet when you were there, no?

Could it possibly be old stains from the old leaky roof? They may have replaced some sheathing.
I know Florida gets wind and rain, but that seems extreme for wicking. If it is that, the stained soffits would be dripping wet when you were there, no?
But maybe this only occurs when the wind hits that side.

The black color could be asphalt or mold, dead or alive, or carbon from a nearby highway. Maybe it is carbon from a BBQ, along with the wicking. Water alone doesn't stain painted metal like that.

Originally Posted by John Kogel

Could it possibly be old stains from the old leaky roof? They may have replaced some sheathing.
I know Florida gets wind and rain, but that seems extreme for wicking. If it is that, the stained soffits would be dripping wet when you were there, no?
But maybe this only occurs when the wind hits that side.

The black color could be asphalt or mold, dead or alive, or carbon from a nearby highway. Maybe it is carbon from a BBQ, along with the wicking. Water alone doesn't stain painted metal like that.

John, thanks
No; original roof only 10 years, funny its only on one side, no nearby highways. Still baffled but I see it a lot, just not as bad. Next time; I'll spend more time and try to figure it out.

Mark,
In the photo it's unclear if there was a sealed down starter shingle under the first row, pretty basic but sometimes these things happen, like not allowing the first course to hang by the drip edge a 1/4 - 1/2 to help shed the runoff (especially on a low slope roof such as this one appears to be). Also did you check that the underlay was over the drip on the eave?

Originally Posted by Mark Hagenlock

Mark,
In the photo it's unclear if there was a sealed down starter shingle under the first row, pretty basic but sometimes these things happen, like not allowing the first course to hang by the drip edge a 1/4 - 1/2 to help shed the runoff (especially on a low slope roof such as this one appears to be). Also did you check that the underlay was over the drip on the eave?

Its different here in Florida; for wind resistance they put the starter and first course flush with the drip edge and put the felt under the drip edge so they can tar seal the starter course on top of the drip edge. I know; I'm from up north and when I came down here I thought wow, this is weird. This is all fine until the tar seal has cooked in the sun for a fear years and then shrinks and cracks allowing water to wick up by capillary action. Ninety percent of sheathing damage I find is at the eaves. Every once in a while; although rare, I find the shingles overlapped at the eave and always suspect it was a home owner install who probably came from up north.

Originally Posted by Mark Hagenlock

Also did you check that the underlay was over the drip on the eave?

In Florida, the underlayment will be under the drip edge with the drip edge sealed to the underlayment with a 4" wide bed of roof cement spanning the joint (2" up on the underlayment, 2" down on the drip edge) and the starter course is set in this 4" wide bed of roof cement, effectively sealing the water out.

Putting the underlayment over the drip edge simply invites high wind events (hurricanes ) to get under the underlayment lift the roof covering off in one big puff (peels the roofing off like pulling off a bandage).

Originally Posted by mark petty

This is all fine until the tar seal has cooked in the sun for a fear years and then shrinks and cracks allowing water to wick up by capillary action.

That is likely because, for years and years, the roofers would spread on the 4" wide bed of roof cement, then scraped it back off (no thickness of it was required) - a 5 gallon bucket of roof cement goes a long way when applied that way as only a thin smear of roof cement was left, and it didn't do much good with all the roof cement scraped back off.

Now they lay a good bed of roof cement and you probably won't see those problems at that joint.

The best way was the older way and that was to actually lay down the 4" wide bed of roof cement (nice and thick) and lay the drip edge in it - that sealed it all down quite nicely, then they applied a 4" wide bed of roof cement on the drip edge to seal starter course down to the drip edge. Once they thought about it, they figured why use seal the drip edge down with roof cement, they are sealing it on top anyway ... shortcuts lead to leaks - my thinking anyway.

Every once in a while; although rare, I find the shingles overlapped at the eave and always suspect it was a home owner install who probably came from up north.

And their roofs will blow off quicker ... ... no snow load to weigh the shingles down.

Originally Posted by Jerry Peck

The best way was the older way

I think the best way is a metal roof in Florida. special drip edge and roof panel formed over it. No place for the water to get under a shingle to begin with, plus they last a LOT longer. They are usually installed with a dual underlayment as well. Material costs are similar, labor is more on the metal roof.

Comp shingles seem to get about half thier stated life in FL, regardless of how good the install was a 25 year tri-tab averages about 12 years…I dont think a 35 to 40 year comp roof will really get 18 to 20 years.

The worst part it that now contractors are selling a "lifetime warranty roof" whatever that means. The warranty I am sure limits the roof the second the house sells, therefore the manufacturer is off the hook early in the game.

Originally Posted by Dirk Jeanis

Comp shingles seem to get about half thier stated life in FL, regardless of how good the install was a 25 year tri-tab averages about 12 years…I dont think a 35 to 40 year comp roof will really get 18 to 20 years.

In Florida, the expected life of composition shingles depends on location as well as quality of the shingles - in South Florida, a 20 year shingle might have an average life of 8-12 years, a 35-40 year shingles might make it 15-20 ... might; in Central Florida, the life would be closer to 20 year/12-18 years and 35-40 year/20-25 years; in North Florida, I suspect the life is closer to manufacturers life expectancies.

This is because the UV from the sun in South Florida just plain kills the composition shingles, and Central Florida is far enough north that the UV from the sun is not so bad, and North Florida is probably similar to surrounding states, which would be considered normal life expectancy.

Metal is not real good here, not galvanized or galvalume, due to so much of the state being "on or near" the coast and corrosion and high humidity. Copper is just too expensive for most people.

That is why there is so much concrete tile in Florida, especially in South Florida. Good tile will support your weight if the tile is properly laid and the person walking on the tile walks on the headlap overlap ... step in the middle of the tile and some will support you, others will not (years ago the tile was stronger and pretty much all of the tile would support you when you stepped in the middle of the tile, but quality has come down. Clay tile is not as strong as concrete tile and walking it is more risky (easier to break the tile), however, clay tile is typically where you find more problems from incorrect installations of the tile and more loose tiles than with concrete tiles (unless the tile is mechanically attached - screwed down).

I've seen this before with cellulose insulation when it gets moist .