Flashing a damn silly window

[Duncanr]

Gentlemen,

This is hard to explain, but let me try anyway. If I could work out how to attached photographs here, I would, so anyone who can tell me that bit will save confusion. Anyway ....

I have a window in a wall above a tiled roof (slope about 30 degrees). The window (fixed light) is triangular as its top edge is horizontal, and its bottom edge follows the line of the roof below. Imagine a triangle on its side, about 2000mm along the top (horizontal) edge and 1000 along the vertical, with the top corner a right angle. Butting to the vertical of the window frame (i.e. down the lower roofline) is a brick wall, to which the lower roof also attaches. The lower roof forms a right angle with the window, i.e. is in the horizontal to the window. Ahhh, architects!

The house is 40 years old, and my guess the window has ALWAYS leaked in one way or another. There are generations of silcone and extra tin and /or lead flashings up there. We have owned the house for about a year, and the first thing I did was replaced most the existing aluminum flashings with 400mm lead, a great improvement.

The problem is that the window is recessed into the brickwork about 80mm, forming a step at its lowest corner. Water runs down the window/roof flashed junction and naturally hits this corner.

As I want to replace the window with a double-glazed composite window, now is the time to re-do this mess of flashings. The question is, using what, and how? It seems to me that the best way would be a fabricated lead flashing, soldered to form a complex lower corner. Say that to a roofer in Australia - did I mention that bit - and get blanks stares. I guess the alternative is Aluminium flashing, no idea if silicon and rivets will form a durable waterproof junction in such light material.

So, suggestions from the experts? No, bricking up the window is not a choice.

Duncanr

Photos now below. Breezer, you sound like you know what you are doing, tell me if you can see 'em, then someone can fix the problem.

http://i91.photobucket.com/albums/k306/Duncanr/PICT0051.jpg
http://i91.photobucket.com/albums/k306/Duncanr/PICT0050.jpg
http://i91.photobucket.com/albums/k306/Duncanr/PICT0049.jpg
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[breezer]

If I could work out how to attached photographs here, I would

see this

 

[NS215]

well i'd suggest a new window with a window sill then put one piece of lead from under the sill onto the roof and silicone all the way round the window and job should be sorted

 

[breezer]

Photos now below. Breezer, you sound like you know what you are doing, tell me if you can see 'em, then someone can fix the problem.

http://i91.photobucket.com/albums/k306/Duncanr/PICT0051.jpg
http://i91.photobucket.com/albums/k306/Duncanr/PICT0050.jpg
http://i91.photobucket.com/albums/k306/Duncanr/PICT0049.jpg
[/url]

I can, but they look even better if you show them like this

 

[Duncanr]

OK, what's that trick?

Not that this dialogue is getting the windiw flashed just yet ... but I know that'll come with time!

Duncanr

 

[paulpolly]

Duncanr, lovely window (minimising the sarcasm). Here goes;

Firstly stick to lead flashings, you cant go wrong.
The flashing detail is simple enough for a competent roofer. What you really need to do is to get a better detail. I have briefly scanned the enclosed photographs and have you considered making the window smaller??
What i mean is; if you were to remove the window and insert a 3" x 2" (75 x 50mm) or a 3" x 3" along where the lower window frame was, then you have built a better upstand for your flashing to fix to. I understand that this may reduce the size of your lovely window but would slove the under sill detail. The lead would run up to the underside of the new composite plastic window, or even tuck inder the new window sill by a couple of inches. working out a corner flashing detail for this situation should be left to a skilled and experinced roofer. Bit of a nip and tuck situation at the corner but faily straight forward.

i tried to attach a small detail to explain better (sorry), if you want it i will try a bit harder????

 

[Nige F]

For what it`s worth I`d check out an old Aus plumber who can weld lead ........called leadburning here in UK.......funnily enough I`ve got a job with several windows like that to do for a M8....anyways the lead should form a tray under the window and upstand inside .....that`s assuming your plumbers are taught leadwork .............sounds like your roofers are like some over here...their families should`ve been transported to you years ago

 

[Duncanr]

Thanks Nigel, that's my instinct too.

Roofers over here seem to have 15 solutions to every problem, all called "silicon". If silicon is the answer, I'll do a better = more careful - job than they will.

How hard is it to solder/leadburn? Is it a straigthforward job for a patient amateur, or "don't go there" territory? It is partly a question of working in with the window fitters, the full extent of the requirement won't be known until the old window comes out.

Duncanr