sealing window frames from the rain


S

Simon Wilson

Hi,

I wonder if anyone can suggest a good way to seal an old window frame in
a stone house from the rain please.

We've discovered that the rain comes through under the bottom part of
the window frame that sits on top of a flat granite block. The are no
drainage channels or ridges to stop the rain driving in, especially in
the right hand corner. There's a picture here:
http://www.flickr.com/photos/siwilson/6143683012/

I've raked out all the old mortar, various bits of silicone sealant, old
socks etc. from underneath, and re-mortared with a hydraulic lime.

In heavy rain it still seeps underneath as of course the lime is porous.
Also over time the wood's going to move etc. and cracks will open up.

For now, I've just blathered on water repellant, but I don't think
that's a good long term solution. Can anyone think of a solution that
won't look too gash. So far I've thought of either slapping silicone
sealant all over it (which I think will look awful), or white flashing
tape (ditto).

TIA,

/Simon
 
Ad

Advertisements

J

Jim K

Hi,

I wonder if anyone can suggest a good way to seal an old window frame in
a stone house from the rain please.

We've discovered that the rain comes through under the bottom part of
the window frame that sits on top of a flat granite block. The are no
drainage channels or ridges to stop the rain driving in, especially in
the right hand corner. There's a picture here:http://www.flickr.com/photos/siwilson/6143683012/

I've raked out all the old mortar, various bits of silicone sealant, old
socks etc. from underneath, and re-mortared with a hydraulic lime.

In heavy rain it still seeps underneath as of course the lime is porous.
Also over time the wood's going to move etc. and cracks will open up.

For now, I've just blathered on water repellant, but I don't think
that's a good long term solution. Can anyone think of a solution that
won't look too gash. So far I've thought of either slapping silicone
sealant all over it (which I think will look awful), or white flashing
tape (ditto).

TIA,

/Simon
erm frame sealant?

or how about some squirty foam injected under from in/outside topped
off with your choice of sealant? low expansion flavour is available if
you're worried about distorting the frame....or maybe gorilla glue if
the gap is tiny?

Jim K
 
S

Simon Wilson

erm frame sealant?
On some of the windows the gap is about 30mm, I don't know how to apply
a frame sealant to that size gap that wouldn't look like a dog's breakfast.
or how about some squirty foam injected under from in/outside topped
off with your choice of sealant?
On one of the windows I did try the shaving foam stuff but had trouble
trying to get it to adhere (I did wet everything per the instructions).
I'm still left with how to get a neat finish.
low expansion flavour is available if
you're worried about distorting the frame
Not an issue, it's pretty strong as far as I can tell.
....or maybe gorilla glue if
the gap is tiny?
Not sure what that is, but it's not a tiny gap on some of the windows.

Thanks.
 
J

Jim K

On some of the windows the gap is about 30mm, I don't know how to apply
a frame sealant to that size gap that wouldn't look like a dog's breakfast.
apply on top of squirty expanding foam.....
On one of the windows I did try the shaving foam stuff but had trouble
trying to get it to adhere (I did wet everything per the instructions).
I'm still left with how to get a neat finish.
adhere? how did it fall out?
let it cure (few hours) then cut it back to leave room for the frame
sealant.....

Not sure what that is, but it's not a tiny gap on some of the windows.
(google is your friend, but n/a now we know what size gaps you are on
about).

Jim K
 
D

Dean Heighington

Simon Wilson said:
Hi,

I wonder if anyone can suggest a good way to seal an old window frame in
a stone house from the rain please.

We've discovered that the rain comes through under the bottom part of the
window frame that sits on top of a flat granite block. The are no
drainage channels or ridges to stop the rain driving in, especially in
the right hand corner. There's a picture here:
http://www.flickr.com/photos/siwilson/6143683012/

I've raked out all the old mortar, various bits of silicone sealant, old
socks etc. from underneath, and re-mortared with a hydraulic lime.

In heavy rain it still seeps underneath as of course the lime is porous.
Also over time the wood's going to move etc. and cracks will open up.

For now, I've just blathered on water repellant, but I don't think that's
a good long term solution. Can anyone think of a solution that won't look
too gash. So far I've thought of either slapping silicone sealant all
over it (which I think will look awful), or white flashing tape (ditto).

TIA,

/Simon
It looks and sounds to me like you need to get the water away from the cill
and stop it pooling against the frame. It obviously isn't draining away
from the cill- is there a slope to it? If not, then I would suggest
cloaking it with lead and forming a run off. Lap the lead up onto the
bottom of the frame and cover it with a strip of wood or PVC with perhaps a
rebate along it's length to house the thickness of the lead. You could
alternatively apply a sloped band of screed on top of the stone cill but
the lead might look better and more 'natural'. It all depends if the water
is pooling and won't naturally drain off!
 
T

The Natural Philosopher

Dean said:
It looks and sounds to me like you need to get the water away from the cill
and stop it pooling against the frame. It obviously isn't draining away
from the cill- is there a slope to it? If not, then I would suggest
cloaking it with lead and forming a run off. Lap the lead up onto the
bottom of the frame and cover it with a strip of wood or PVC with perhaps a
rebate along it's length to house the thickness of the lead. You could
alternatively apply a sloped band of screed on top of the stone cill but
the lead might look better and more 'natural'. It all depends if the water
is pooling and won't naturally drain off!
Actually that's a decent enough idea. But I am dubious that the lead to
wood seal will be maintained.

Since the OP mentions granite, which is impervious, I still think the
'rake out the mortar and use the expanding foam' is the way to go.
its possible to use a decorative lime mortar fillet at the front for
virtual reasons, or a paintable frame sealer. I'd go for the latter frankly.

So out with the mortar, in with the foam, trim that back and go for
frame sealer last of all.
 
Ad

Advertisements

S

Simon Wilson

It looks and sounds to me like you need to get the water away from the cill
and stop it pooling against the frame.
Ideally, yes.
It obviously isn't draining away
Indeed not.
from the cill- is there a slope to it?
No.

If not, then I would suggest
cloaking it with lead and forming a run off. Lap the lead up onto the
bottom of the frame and cover it with a strip of wood or PVC with perhaps a
rebate along it's length to house the thickness of the lead.
Hmm. Interesting. That might not look too bad. said:
You could
alternatively apply a sloped band of screed on top of the stone cill but
the lead might look better and more 'natural'. It all depends if the water
is pooling and won't naturally drain off!
Yes, some of the windows had been bodged with a wedge of mortar, but
badly - wasn't doing any good at all and also looked rubbish.

Thanks,
 
R

robgraham

Ideally, yes.


Indeed not.




Yes, some of the windows had been bodged with a wedge of mortar, but
badly - wasn't doing any good at all and also looked rubbish.

Thanks,
I've got old wooden windows in a stone house and I've got wooden
windows in the modern extension.

It is noticeable that, for a start, the stone cills are all cut so
that there is a several degree run of angle. The other feature is
that the wooden window cill, also angled for run off, is bedded onto a
small raised lip so that the water can run off it and drip onto the
stone.

When the extension was built - concrete cills with dpm and drips - all
the windows leaked at the cills under storm conditions. The builder
failed to resolve this. I then noticed that for some inexplicable
reason he had taken a saw along the wooden window cills and removed
the overhanging drip so the water was running off and straight down
into the mastic seal. I found that all the leaking stopped
immediately when I screwed and glued a nominally 25mm wide batten back
on, containing a drip such that the water was thrown clear of the
window to concrete seal.

It may not be that easy to do, but I would make sure that the stone
cill has a slope on it, and I would add a batten of wood with a drip
to the window frame such that the water is away from the wood/ stone
joint water and has somewhere to go.
 
J

Jim K

Actually that's a decent enough idea. But I am dubious that the lead to
wood seal will be maintained.
mmm a 30mm gap filled with foam and covered in sealant should take
some getting past......
also how would lead be sealed to *everything* stop any water getting
behind it? won;t it also be a pikey magnet?

think I;d try foam n sealant first ;>)

Jim K
 
S

Simon Wilson

I've got old wooden windows in a stone house and I've got wooden
windows in the modern extension.

It is noticeable that, for a start, the stone cills are all cut so
that there is a several degree run of angle. The other feature is
that the wooden window cill, also angled for run off, is bedded onto a
small raised lip so that the water can run off it and drip onto the
stone.

When the extension was built - concrete cills with dpm and drips - all
the windows leaked at the cills under storm conditions. The builder
failed to resolve this. I then noticed that for some inexplicable
reason he had taken a saw along the wooden window cills and removed
the overhanging drip so the water was running off and straight down
into the mastic seal. I found that all the leaking stopped
immediately when I screwed and glued a nominally 25mm wide batten back
on, containing a drip such that the water was thrown clear of the
window to concrete seal.

It may not be that easy to do, but I would make sure that the stone
cill has a slope on it, and I would add a batten of wood with a drip
to the window frame such that the water is away from the wood/ stone
joint water and has somewhere to go.
Yes in an ideal world this is probably the best, but, to do this I think
involves more work/cash that I can afford to put into it. The sill does
slope slightly, but not enough to stop the wind driving the water uphill.
 
S

Simon Wilson

Actually that's a decent enough idea. But I am dubious that the lead to
wood seal will be maintained.
I'm going to take a look but it may be possible take the lead all the
way up, and a short distance under the opening windows, which would
solve that problem.
Since the OP mentions granite, which is impervious, I still think the
'rake out the mortar and use the expanding foam' is the way to go.
its possible to use a decorative lime mortar fillet at the front for
virtual reasons, or a paintable frame sealer. I'd go for the latter
frankly.

So out with the mortar, in with the foam, trim that back and go for
frame sealer last of all.
One one window, we did try crazy foam followed by sealer, with the
intention of putting a mortar bead over the top for looks. But, it still
seemed to leak with the 'bucket of water' test. It did turn out
subsequently that the water was coming between the window and the frame
in this case - we have solved that now.

Many attempts with sealant have obviously been tried in the past, hence
my feeling it really needs something different. Over the years the
leaking has caused a huge amount of damage to the wooden lintels in the
floor below.
 
Ad

Advertisements

P

Phil L

Simon said:
Hi,

I wonder if anyone can suggest a good way to seal an old window frame
in a stone house from the rain please.

We've discovered that the rain comes through under the bottom part of
the window frame that sits on top of a flat granite block. The are no
drainage channels or ridges to stop the rain driving in, especially in
the right hand corner. There's a picture here:
http://www.flickr.com/photos/siwilson/6143683012/

I've raked out all the old mortar, various bits of silicone sealant,
old socks etc. from underneath, and re-mortared with a hydraulic lime.

In heavy rain it still seeps underneath as of course the lime is
porous. Also over time the wood's going to move etc. and cracks will
open up.
For now, I've just blathered on water repellant, but I don't think
that's a good long term solution. Can anyone think of a solution that
won't look too gash. So far I've thought of either slapping silicone
sealant all over it (which I think will look awful), or white flashing
tape (ditto).
Cut a piece of wood the width of the window and about 50mm to nothing in
height, so that the 50mm part is sat on the cill - a triangular section
IYSWIM

Set this in silicone on the cill and affix to the bottom of the frame with
screws, sealing the gap between both with more silicone, then remove excess
silicone and paint so that it matches the frame.
 
D

Dean Heighington

Simon Wilson said:
Ideally, yes.
Indeed not.

Hmm. Interesting. That might not look too bad. <adds to list to consider>
Yes, some of the windows had been bodged with a wedge of mortar, but
badly - wasn't doing any good at all and also looked rubbish.

Thanks,
Welcome. As for joining lead to wood, brick glass et al... Use leadmate or
flashpoint. In essence you will be making a lead 'tray' to cover the cill.
The PVC (or wood) cloaking will hide the edge between the timber frame and
the lapped up lead.
 
H

harry

Hi,

I wonder if anyone can suggest a good way to seal an old window frame in
a stone house from the rain please.

We've discovered that the rain comes through under the bottom part of
the window frame that sits on top of a flat granite block. The are no
drainage channels or ridges to stop the rain driving in, especially in
the right hand corner. There's a picture here:http://www.flickr.com/photos/siwilson/6143683012/

I've raked out all the old mortar, various bits of silicone sealant, old
socks etc. from underneath, and re-mortared with a hydraulic lime.

In heavy rain it still seeps underneath as of course the lime is porous.
Also over time the wood's going to move etc. and cracks will open up.

For now, I've just blathered on water repellant, but I don't think
that's a good long term solution. Can anyone think of a solution that
won't look too gash. So far I've thought of either slapping silicone
sealant all over it (which I think will look awful), or white flashing
tape (ditto).

TIA,

/Simon
You can buy additives to put in cement to make it waterproof.
ButI think the foam is best. It deteriorates in sunlight, must be
covered up.
 
D

Dean Heighington

Jim K said:
On Sep 13, 1:14 pm, The Natural Philosopher <[email protected]>
mmm a 30mm gap filled with foam and covered in sealant should take
some getting past......
also how would lead be sealed to *everything* stop any water getting
behind it? won;t it also be a pikey magnet?

think I;d try foam n sealant first ;>)

Jim K
The gap is to large for foam and sealant when water is pooling against
it... We're looking at getting the water away... Not designing a tanking
system!
 
J

Jim K

The gap is to large for foam and sealant when water is pooling against
it...
really? how deep is the pool? OP says driven rain....
We're looking at getting the water away... Not designing a tanking
system!
thought your lead lining sounds rather more like a tanking attempt
than anything else mentioned thus far... how do you propose to
reliably seal these sheets of lead at the sides of the cill? (Leadmate
cracks after a few hot cold cycles BTW)

Worst thing possible is the "pool" of water is still there under your
lead......

Jim K
 
Ad

Advertisements

D

Dean Heighington

Jim K said:
really? how deep is the pool? OP says driven rain....
Not when asked.
thought your lead lining sounds rather more like a tanking attempt
than anything else mentioned thus far... how do you propose to
reliably seal these sheets of lead at the sides of the cill? (Leadmate
cracks after a few hot cold cycles BTW)
I wrote... Slope the lead away from the frame. And I didnt propose sheets.
Use whatever as packing underneath. I would solder the lead at the seams
but it depends on the OPs abilities. Leadmate is as good as anything and
with proper laps it will last. I have been back to wall chases months after
using a lead sealant and the stuff is still viscous and malleable so 'I'
don't see any problem with drying out.
Worst thing possible is the "pool" of water is still there under your
lead......
Then dont let it get underneath.
Properly dressed lead has worked for centuries and it's easy to work with.

But if you still disagree (and so to does the OP) then cover the whole cill
with a suitably selected stone tile (or cuts to fit the recess) slope them
up at the back using a bed of mortar and route a channel into the base if
the timber frame and dress with a thin lead flashing down from the frame
onto the tiled cill.

But I still stand by my lead solution... Cheap, quick, easy to fabricate
and will suit the situation aesthetically.

Let gravity do the work and get the water away.

Or how about some PVC quardrant to cover the 30mm gap? Reduce the width of
the mastic seal and you've much more chance of keeping it waterproofed.
D.
 
S

Simon Wilson

really? how deep is the pool? OP says driven rain....


thought your lead lining sounds rather more like a tanking attempt
than anything else mentioned thus far... how do you propose to
reliably seal these sheets of lead at the sides of the cill? (Leadmate
cracks after a few hot cold cycles BTW)

Worst thing possible is the "pool" of water is still there under your
lead......
Hmmm didn't want to start a Jihad.

Going down the lead route will definitely require careful attention to
the edges. I _may_ be able to grind a slot in for the sides (but again
it's granite). There are many examples in this house of problems just
being covered up, which has made it all worse. (eg, external oak lintel,
full of woodworm/deathwatch, had had a million nails banged into it, and
then rendered over)

Whether I use the shaving foam or old socks doesn't really matter, two
things put me off using the sealer a) I don't think I could get a decent
finish, especially on the windows with the large gaps b) it's obvious
sealer has been applied several times before, and for whatever reason
(shrinkage/expansion), it hasn't survived.

It is more driven rain than pooling I guess, but again there is little
to no slope on the sill.

<Thinks> also, if you look in the photo, some of the sills have cracks
in them. Lead would cover them up too.

Decisions, decisions.
 
D

Dean Heighington

Simon Wilson said:
Hmmm didn't want to start a Jihad.

Going down the lead route will definitely require careful attention to
the edges. I _may_ be able to grind a slot in for the sides (but again
it's granite). There are many examples in this house of problems just
being covered up, which has made it all worse. (eg, external oak lintel,
full of woodworm/deathwatch, had had a million nails banged into it, and
then rendered over)

Whether I use the shaving foam or old socks doesn't really matter, two
things put me off using the sealer a) I don't think I could get a decent
finish, especially on the windows with the large gaps b) it's obvious
sealer has been applied several times before, and for whatever reason
(shrinkage/expansion), it hasn't survived.

It is more driven rain than pooling I guess, but again there is little to
no slope on the sill.

<Thinks> also, if you look in the photo, some of the sills have cracks in
them. Lead would cover them up too.

Decisions, decisions.
Jihad lol:) men and their pride eh :)
If it was me doing the job with all the constraints mentioned, I would go
the lead route as it's more traditional and if done properly would look
like it was meant to be.

I would dress the lead so that it covers the Cill and folds up at the
sides and at the back using a mitred overlap at the corners which is the
only bit that would need sealing. It's a tricky form to fabricate but
doable... Make the template out of card or brown paper before using the
lead to get the perfect fit. You can then chase the upstand edges into the
timber frame at the back and into the mortar joints of the brick at the
sides.

Or see my other idea of using a stone tile to raise the cill above the base
joint of the timber frame and then use a thin lead flashing over onto the
tiled tip of the cill.

If you're still not sure what I mean, let me know and I'll sketch it cos
words and typing can't do what a simple sketch can ;)
 
Ad

Advertisements

J

Jim K

Not when asked.
tho the OP actually says it and later cill does "have a slope"........
I wrote... Slope the lead away from the frame. And I didnt propose sheets.
?????? if not sheets how do you propose to stop the rain being driven
under the lead "bits" covering the cills then?
Use whatever as packing underneath. I would solder the lead at the seams
but it depends on the OPs abilities. Leadmate is as good as anything and
with proper laps it will last. I have been back to wall chases months after
using a lead sealant and the stuff is still viscous and malleable so 'I'
don't see any problem with drying out.
"I" do.
Then dont let it get underneath.
doh!?

Properly dressed lead has worked for centuries and it's easy to work with.
I for one have never seen it used as you imagine


Jim K
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Top