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  • May 9th, 2019 1:34 pm
[OP]
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Leaking Skylight

UPDATE ISo just to close this thread - especially those with a Velux skylight, the skylight was NOT leaking. It indeed was condensation. I cannot believe what a hassle this whole ordeal has been, and how some tradespeople are so incompetent, dishonest and untrustworthy. If anyone else thinks they may have a potential leak with a Velux skylight - be sure to consult with a reputable and certified Velux installer. Do NOT go with a non-certified Velux installer or you will will get wrong advice and potentially make things worse!! Even if the company is a Velux installer, the estimator may not be. See post #26 for further details.

===========ORIGINAL MESSAGE ==================
I have a skylight in my bathroom on a very high and steep roof. I noticed brown drip stains on the edge of the ceiling (the roof is surrounded by trees so the brown is from tannins) and on a rare occasion the droplets make it to the floor but I've only seen that twice in 2.5 years. I notice the drip stains mostly when the snow is melting (not when it's raining). Is this just condensation or would it be leaking? The odd thing there are clear the drip stains which start (or only show) mid-way down (not from the very top) that run all the way down to ceiling as you should able to see this from the pictures. Just trying to make sense of this and if there are any preventative measures I should be taking.

Additionally, cleaning is virtually impossible unless I can manage to get an extended ladder in a small bathroom. An extended handle on a broom or mop wouldn't be long enough - any ideas how to clean the dust and other debris that has accumulated?

Hopefully the pictures give you an idea of the situation - but the finer detail seem not to show in the pictures online as they do on my phone.
Last edited by hierophant on May 7th, 2019 7:07 pm, edited 4 times in total.
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That's a crazy deep window, unless your phone is exaggerating it.
The stains most likely aren't from trees. Either it's either condensation or the roof is leaking.
One of the issues with a window that deep is that there isn't enough airflow, and warm moist air rises up the shaft, then water vapour condenses on the glass. It then builds up and runs downwards.
If the window (known as the sealed thermal unit) is not argon filled, or the seals have failed, the condensation will be even greater. If that is the case, the sealed thermal unit can be replaced. Be forewarned; the Velux units are very expensive. They need to be tempered glass as well as laminated for safety.
[OP]
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My camera isn't exaggerating the depth - it really is that high/deep...I have a very steep roof.
MrFrugal1 wrote:
Feb 22nd, 2019 11:32 pm
Either it's either condensation or the roof is leaking.
I think it's safe to say I've already determined it's one of the two - I need help figuring out which one it is :)

If it was a leak, wouldn't it leak all the time or at least when it's raining? Are there some telltale signs to verify? It's been doing this pretty much since I moved in (2.5 years) - every month or so I see a few brown dried brown stains...thought I just look into it in case it becomes a bigger problem.
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hierophant wrote:
Feb 22nd, 2019 11:41 pm
I think it's safe to say I've already determined it's one of the two - I need help figuring out which one it is :)

If it was a leak, wouldn't it leak all the time or at least when it's raining? Are there some telltale signs to verify?.
It could be both a leak and condensation.

Leaks can be difficult to pinpoint. Wind and rain direction, snow and ice build up and melt, can cause intermittent leaks both large and small, which can be puzzling. A small leak can not show itself for hours or days after a weather event.

In your case, since it's a bathroom, I'll hazard to guess it's just condensation. Even if you run the exhaust fan, water vapour is going to condense on the walls and on the surface of windows.
The brownish staining is probably just airborne particulate from cooking, smoking,etc that the water is picking up off the walls or window surfaces.

As far as cleaning the window, you can get a telescopic extension pole and attach a foam /squeegee head on to it. You can find them in the paint section at your big box stores.
Telescopic pole
It'll take some finesse, but I can't think of any other way. You'll have to ask the genius who decided to put that small a window in that deep of a bay.
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How old is the skylight? Like windows, they have only a given set lifespan before they need to be replaced.

Replacement Velux skylights aren't that expensive as they once were, as that is all that I will specify for home designs/renos and use in my own home. An example a fixed curb mount double paned egas something like 28" x 36" assembly costs less than $450 for the unit. Where they start getting expensive is adding features to the basic unit, such as internal blinds, automatic openers, etc, which then easily triple the costs.

I am suspecting your have a seal leak somewhere that the melting snow forms ice dams up against the exterior skylight flashing, and finds it's way in slowly. Rain doesn't leak in because it isnt allowed to pool like melting snow does in the colder weather ... I've seen ice dams create too many crazy mysterious leaks over the years.

Where Ice Dams Can Form
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Jojo_Madman wrote:
Feb 23rd, 2019 10:15 am
I am suspecting your have a seal leak somewhere that the melting snow forms ice dams up against the exterior skylight flashing, and finds it's way in slowly. Rain doesn't leak in because it isnt allowed to pool like melting snow does in the colder weather ... I've seen ice dams create too many crazy mysterious leaks over the years.
+1, its likely building up on the high side and seeping in. This will only get worse OP, deal with it before the drywall box needs repair.
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MrFrugal1 wrote:
Feb 23rd, 2019 9:31 am
In your case, since it's a bathroom, I'll hazard to guess it's just condensation. Even if you run the exhaust fan, water vapour is going to condense on the walls and on the surface of windows.
The brownish staining is probably just airborne particulate from cooking, smoking,etc that the water is picking up off the walls or window surfaces.
Just as an FYI, the tub/shower is not used in this bathroom . I was thinking the condensation was from the window dripping down.
Jojo_Madman wrote:
Feb 23rd, 2019 10:15 am
How old is the skylight? Like windows, they have only a given set lifespan before they need to be replaced.
The house is about 22 years old so likely that's the age of the skylight. Before replacing it I want to ensure that's actually the problem. What professional would I call (roofer, window)?
Zamboni wrote:
Feb 23rd, 2019 11:07 am
+1, its likely building up on the high side and seeping in. This will only get worse OP, deal with it before the drywall box needs repair.
My problem is that I don't know where to start in dealing it. I need to know what the problem is or at least who to call to diagnose it before I start fixing it. If it's seal leak does the window need to be replace or can the seal be fixed?
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It's time to be replaced in my opinion.

Generally speaking, lifespan is somewhere between 15-20 years depending on brand, style, location, climate, sun exposure, etc.

Call a roofer who specifically states that they will do skylight replacements in their ads or website. The reason I say this, is that you want to ensure the replacing doesnt compromise the integrity of the roofing material causing other leaks. They will also be able to install new flashing to eliminate or minimizing ice dams in the future.

They also may be able install something as an intermediate fix, such as flashing, allowing you to delay replacing the skylight until warmer weather or even until the roof needs replacing.
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Thanks everyone. I will call some roofers who specialize in skylights on Monday to see if they come and take a look and give me idea of the problem and estimate.
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hierophant wrote:
Feb 23rd, 2019 11:53 am
Just as an FYI, the tub/shower is not used in this bathroom . I was thinking the condensation was from the window dripping down.
The house is about 22 years old so likely that's the age of the skylight. Before replacing it I want to ensure that's actually the problem. What professional would I call (roofer, window)?
My problem is that I don't know where to start in dealing it. I need to know what the problem is or at least who to call to diagnose it before I start fixing it. If it's seal leak does the window need to be replace or can the seal be fixed?
I'm fairly confident that this is a condensation issue, not the roof/shingles.
At 22 years, the seal on the thermal unit is probably pooched. I know it's hard to tell looking up at the sky, but does it appear foggy at times? If that happens, it loses substantial R-value, and that would cause condensation. When it's really cold, frost will accumulate and then later melt.
Replacing the sealed thermal unit would be the logical place to start, if it's even possible with that make of window. Otherwise, it'll be a new window entirely.

A window installer is who you want, and one that sells and installs skylights. Don't let a roofer touch it. I've seen guys install the flashings incorrectly because, well, they are roofers.

Personally, I hate skylights for this exact reason. I've been in too many homes and seen crumbling drywall caused by them. If it were me, I'd close the openings up, fill the cavity with insulation and call it a day.
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hierophant wrote:
Feb 23rd, 2019 11:53 am
The house is about 22 years old so likely that's the age of the skylight. Before replacing it I want to ensure that's actually the problem. What professional would I call (roofer, window)?

My problem is that I don't know where to start in dealing it. I need to know what the problem is or at least who to call to diagnose it before I start fixing it. If it's seal leak does the window need to be replace or can the seal be fixed?
It might be easily visible to whoever goes onto the roof what the issue is; most common issue is the flashing and guy inspecting could use good product like karnak to seal, either temp or permanent depending on the issue.
Glass to frame leak, silicone until skylight can be swapped out.
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MrFrugal1 wrote:
Feb 23rd, 2019 12:30 pm
I'm fairly confident that this is a condensation issue, not the roof/shingles.
At 22 years, the seal on the thermal unit is probably pooched. I know it's hard to tell looking up at the sky, but does it appear foggy at times? If that happens, it loses substantial R-value, and that would cause condensation. When it's really cold, frost will accumulate and then later melt.
Replacing the sealed thermal unit would be the logical place to start, if it's even possible with that make of window. Otherwise, it'll be a new window entirely.

A window installer is who you want, and one that sells and installs skylights. Don't let a roofer touch it. I've seen guys install the flashings incorrectly because, well, they are roofers.

Personally, I hate skylights for this exact reason. I've been in too many homes and seen crumbling drywall caused by them. If it were me, I'd close the openings up, fill the cavity with insulation and call it a day.
I don't think it's roof either and I don't think anyone said it was. The consensus seems to be the window and/or seal around the window. I have never seen the skylight fog up.

I definitely will not be filling up the cavity - totally unnecessary. Things need to be repaired after a certain amount of time regardless of what it is - that's just life no reason to go extremes because every 20 years something needs to be repaired ...plus I like the natural light and makes the bathroom look even nicer.
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The brown staining is most likely from the rotting wood framework somewhere within the skylight itself, which has occurred from 20 years or more of being in service.

From anyone with experience, it's common indication that the skylight is overdue to be replaced and now leaking under the right curcumstances. It's taken this long for it to work it's way inside.

If it was just condensation as some may be suggesting, it wouldn't be brown in colour ...

Window guys are good for vertical windows only from my experience, and will only blame the roofers when there is an issue. A reputable roofer who does skylights understand proper flashing and sealing to insure water and snow coming down along the roof are redirected away properly.

Skylights are a beautiful thing when proper done in homes, and I try to incorporate them into any home designs or renovations I've done ...
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Jojo_Madman wrote:
Feb 23rd, 2019 1:14 pm
The brown staining is most likely from the rotting wood framework somewhere within the skylight itself, which has occurred from 20 years or more of being in service.

From anyone with experience, it's common indication that the skylight is overdue to be replaced and now leaking under the right curcumstances. It's taken this long for it to work it's way inside.

If it was just condensation as some may be suggesting, it wouldn't be brown in colour ...

Window guys are good for vertical windows only from my experience, and will only blame the roofers when there is an issue. A reputable roofer who does skylights understand proper flashing and sealing to insure water and snow coming down along the roof are redirected away properly.

Skylights are a beautiful thing when proper done in homes, and I try to incorporate them into any home designs or renovations I've done ...
Everything you said makes sense. I'm assuming that skylight windows (because of greater exposure to the elements, positioning, gravity, etc.) require maintenance sooner than vertical windows? I ask because the windows in the rest of house (which are probably the same age) seem to be in relatively good shape...well my heating bills aren't that high lol

Side note - if anyone is contemplating buying a 20 year-old house - consider that MANY things will need replacing at this time interval. The previous owners lucked out (well they actually ignored or didin't pay attention to a lot of things and didn't do much to maintain the home) and I got stuck with replacing so many things lol. Fortunatley roof was done in 2012 so I have a bit of time for that. Not complaining I LOVE my house and got it for a reasonable price and value has gone up significantly.
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hierophant wrote:
Feb 23rd, 2019 1:25 pm
Everything you said makes sense. I'm assuming that skylight windows (because of greater exposure to the elements, positioning, gravity, etc.) require maintenance sooner than vertical windows? I ask because the windows in the rest of house (which are probably the same age) seem to be in relatively good shape...well my heating bills aren't that high lol

Side note - if anyone is contemplating buying a 20 year-old house - consider that MANY things will need replacing at this time interval. The previous owners lucked out (well they actually ignored or didin't pay attention to a lot of things and didn't do much to maintain the home) and I got stuck with replacing so many things lol. Fortunatley roof was done in 2012 so I have a bit of time for that. Not complaining I LOVE my house and got it for a reasonable price and value has gone up significantly.
Welcome to home ownership, 101.
If you thought a home was a static investment that would require no further input, you were wrong.
Houses are like anything else; systems that work together, have lifespans, and are impacted by their occupants activities.

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