Velux VS6 leak - openings at bottom of window

[Jim B]

I have 10 Velux electric venting skylings on my house that were installed when the house was built 17 years ago. The roof is curved with a membrane.

One or two of the windows leak enough to damage the drywall lining.

I have resealed all the glass and tested it so I know there is no leaking there.

Here is the weird issue.

The bottom of the windows have openings at each side and visible wood. I have searched the web but cannot find any pictures or information on these old windows.

It looks like somethign is missing but it is missing on all 10 windows?

Does anyone have any idea how this should have been closed off, it is not obvious how that would be done.

I cant post a picture for some reason.

many thanks

[kurt]

rename all pics so there's no number, symbols, or anything other than lower case letters. It'll post then.

Put up some pics; hard to know what you're talking about. I have half a dozen of those windows, also about 17 years old; I could probably figure it out if you provide a pic.

[Jim B]

I am new member so that could be the issue. It tells me i cannot upload because I am not logged in but I am. Tried a couple of times with no luck. I will try to post to Flickr.

[Jim B]

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[kurt]

There are several issues with those lites that I'm suspicious of, not the least of which is the curb (or lack of adequacy thereof). In short, I would view installing a lite on a curved membrane roof to be at advanced complexities level, and there's about a thousand questions I've got that you probably can't answer.

The "holes" can't be good. It might be as simple as a dab of caulk (note...as soon as one has to start caulking a skylite, we know it's wrong), or it might (in my view) mean complete removal and reinstallation w/a new curb package.

Skylites are simple. Avoid any installation that relies on caulk as the weather seal. Install in a logistically and technically sound manner and you'll get 20+ years. Velux will normally last in roughly the same time frame as the roof covering; install them right, take care of them (refurbish vinyl flashing, finish wood with a marine grade UV inhibiting finish every 7-10 years, relatively easy), and they'll last a lot longer than most roof coverings.

Make up your own rules (like what appears on this install), and it's anyone's guess, and mine would be much less than 20 years, maybe even months or weeks depending on the weather.

[Jim B]

I know at soem point there will be new windows but there are 10 so it is not a cheap upgrade. Since they dont all leak I will try to get another few years. I agree there are many things about this install that is questionable, slope, height of curb etc. I believe it is not actualy on a curb but a deck mount shimed to fit on the curve hence the low profile.

I am curious how this model of window should look, if there is a peice missing or what. I would like to see a brochure or picture of one installed or just what comes with the original window - baically any clues as too how this should look if installed per Velux instructions. I have email Velux to see if they will give me any clues, unfortunately i cant find any legacy data on their site.

Anyway thanks, if anyone out there has a deck mount VS4 or VS6 that I can see a picture it would help I think.

[Jim Katen]

I was under the impression that those particular skylights weren't supposed to be installed at anything less than a 2:12 slope.

[Jim B]

And just a note that the holes are rectangular each side of the lip coming down from the lid and are 1" wide and 2" high so they cant be caulked, there apears to be a flashing missing.

[Jim B]

Not sure what 2:12 is in degrees but I have been told the VS series were to be installed at 14 degrees or more but I have since seen mention of these older versions needing 18 degrees or more. I think this is a contributing factor but at any slope with these wide open holes and wind will drive rain right under and behind the lid flap and agains the seal which is not bullet proof.

FYI the upper windows are at 12 degrees and dont leak, the lower windows being further down the curve are at 14 degrees and do leak?

[Jim B]

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This shows the place that is not closed off by the lid when it closes.

[kurt]

It's the primary factor, or somewhere right down @ the core.

There's all sorts of curb enhancements, some of the them beyond what even Velux says, that have to be considered when doing this type of roof.

[Tom Raymond]

That's a mess. They're missing proper flashing, they're ganged incorrectly, and the roof pitch is too shallow (you're right about the older units requiring a steeper slope). The flatter slope at the top allows water volume to build and the gang concentrates that volume at the lower units. I'd wager the uppers leak too, the lowers just leak worse.

Those skylights had four brackets at the quarter points on the sides and could be adapted to that curved surface. The current version has an integral aluminum flange on all four sides that must sit on a flat roof deck so a direct replacement won't work. You could have a roofer 'wing it' again with curb mount units, but I would contact Velux commercial and have a proper gang designed for that application. It won't be much more expensive than messing with standard units, and far less when you consider the cost of constant bandaids.