expanding foam with ultra-fine nozzle?

[JakeD]

I'd like to inject some expanding foam between the corrugated asbestos
sheets forming my garage roof, to prevent rainwater ingress, when the wind
is blowing in the same direction as the slope of the roof. The standard
expanding foam canisters have an applicator that is betqwwn 5mm and 10 mm
OD. I need something that is more like 2mm! Can anyone suggest how I might
achieve this? Un fortunately, it would be very difficult to pry the sheets
apart whee the overlap, as they are securely nailed ti the roof joists with
6" roofing nails.

Many thanks...

JD

[Cash]

Is it possible to use a silicone mastic with a fine nozzle end?

Cash

[Dave Liquorice]

On 25 Dec 2013 22:51:01 GMT, JakeD wrote:

> I'd like to inject some expanding foam between the corrugated asbestos
> sheets forming my garage roof, to prevent rainwater ingress, when the
> wind is blowing in the same direction as the slope of the roof.

So along the sheets not up the corrugations where they rest on the
wall plate? I'm surprised water is getting in there, have the sheets
got the correct overlap? Two full crests IIRC.

Foam isn't really the right stuff, from a can it's open not closed
cell so water will get through it. As some one else said a good bead
of exterior grade silicone along the edge of the sheet is probably
you best bet, having cleaned/removed any loose material first.

If the sheets are just nailed on is there any sealing washer under
the nail heads?

--
Cheers
Dave.

[Artic]

JakeD scribbled...

I'd avoid foam, it will continue expanding for some time - as I know to
my cost- and could split the brittle asbestos sheets.

[JakeD]

"Cash" <.............\\@...............//.com> wrote in news:bi19b3FoichU1
@mid.individual.net:

> Is it possible to use a silicone mastic with a fine nozzle end?

I wondered about that. I can give it a try.

However, now I have inspected the underside of the asbestos idn broad
daylight, it looks as though the moisture is actually bleeding through the
affected sheets. Most of the sheets are impervious and dry on the
underside. Just a couple of them seems to be allowing water to bleed
through.

Any suggestions what I could paint onto the top sides of the sheets to
waterproof them? Something clear, that won't colour the sheets would be
ideal, because I don;t want the painted sheets to sook different from the
reat, and the roof is too big to paint the whole lot. Would diluted PVA do
it? Or is there something better?

Thanks to all respondees.

JD

[JakeD]

"Dave Liquorice" <allsortsn...@howhill.com> wrote in
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk:

> So along the sheets not up the corrugations where they rest on the
> wall plate? I'm surprised water is getting in there, have the sheets
> got the correct overlap? Two full crests IIRC.

They have the two-ridge overlap. However, I'm not sure hos much overlap
they have londitudinally (if that's the right word)!

On closer examionation, it looks like water is bleeding through a couple of
the sheets, as the look darker in color, and droplets of water can be seen
on the underside of the ridges.

JD

[D.M.Chapman]

In article <XnsA2A2AA4583...@130.133.4.11>,

JakeD <fgdf...@ghghfgh.com> wrote:

>Any suggestions what I could paint onto the top sides of the sheets to
>waterproof them? Something clear, that won't colour the sheets would be
>ideal, because I don;t want the painted sheets to sook different from the
>reat, and the roof is too big to paint the whole lot. Would diluted PVA do
>it? Or is there something better?

Not sure PVA will put up with repeated wet dry cycles will it?

How about something like http://www.toolstation.com/shop/p56806 ?

Or cheaper (not as good, but maybe good enough?)

http://www.toolstation.com/shop/p17776

Darren

[Cash]

JakeD,

Providing there are no cracks in the sheets, you could spray or brush on a
clear silicone waterproof coating over the whole roof which may help.

My advice though (funds permitting) would be to re-roof with Colour Steel
sheets (can be laid on top of the old sheets[1]) to give long-lasting
weatherproofing[2] as asbestos sheets are a beggar to seal once they become
porus[3].

Have you checked the sealing washers under the fixing to see if they are
doing their job as this could possibly be the cause of the leak - especially
in heavy rain?

[1] This method will also negate having to dispose of the old sheets.

[2] A neighbour of mine did this some five years or so ago to great
effect.

[3] You could also lay UV resistant plastic or pond liner over the
asbestos as a temporary sealing measure and fix the overhanging sheet with
battens screwed into the walls just under the roof eaves.

Cash

[andyn...@gmail.com]

> I'd like to inject some expanding foam between the corrugated asbestos

> The standard expanding foam canisters have an applicator that is betqwwn 5mm
> and 10 mm OD. I need something that is more like 2mm!

Some of the foam guns come with a narrow conical nozzle you can put on the end of the gun (I know the Bond-It Teflon coated one does, actually I wish you could buy extra ones as they wear out).

--
Andy Burns

[Tim Watts]

And one-shot cans (non gun type) tend to have smaller stubes supplied .
--
Tim Watts Personal Blog: http://squiddy.blog.dionic.net/

http://www.sensorly.com/ Crowd mapping of 2G/3G/4G mobile signal coverage

[Martin Brown]

It doesn't expand much but how about the space filling polyurethane glue
that is officially intended for exterior woodwork repairs?

Wear gloves and eye protection when working with it - it is extremely
high tack, water tolerant and somewhat flexible when cured!

--
Regards,
Martin Brown

[Jon Fairbairn]

+1. Does no one know of a source of these things?

--
Jón Fairbairn Jon.Fa...@cl.cam.ac.uk
http://www.chaos.org.uk/~jf/Stuff-I-dont-want.html (updated 2012-10-07)

[JakeD]

d...@auk.kent.ac.uk (D.M.Chapman) wrote in news:l9i4qq$8tl$1...@dont-email.me:

> Not sure PVA will put up with repeated wet dry cycles will it?
>
> How about something like http://www.toolstation.com/shop/p56806 ?
>
> Or cheaper (not as good, but maybe good enough?)
>
> http://www.toolstation.com/shop/p17776

Thank you for these suggestions. The last link above looks like good value.
I'm always a bit wary of buying products where they don't specify the
ingredients (in case I'm just buying diluted PVA, but at double the price).

Can anyone else comment of the suitability of PVA solution and/or Everbuild
Waterseal and/or Thompson's Waterseal?

JD

[JakeD]

"Cash" <.............\\@...............//.com> wrote in

news:bi3sa4...@mid.individual.net:

> Have you checked the sealing washers under the fixing to see if they
> are doing their job as this could possibly be the cause of the leak -
> especially in heavy rain?

Yes, the washers seem okay. I think it's just a couple of the 30-odd sheets
that are letting rainwater bleed through, so I'd like to try the most
affordable-but-effective clear liquid sealant first, before going for
anything more expensive. Thompsons Waterseal or Everbuld Waterseal (are
they the same thing?) look interesting. Has anyone used these products and
found them effective and long-lasting for exterior use?

Many thanks,

JD

[Jim K]

I think for £12 you may as well just have a go & see if it sorts the problem?

Jim K

[JakeD]

Jim K <jk98...@gmail.com> wrote in
news:88fe407d-0822-4eaa...@googlegroups.com:

> I think for �12 you may as well just have a go & see if it sorts the
> problem?

That may be the thing to do, but I thought I'd ckeck first - in case, say,
anyone has found the stuff to have undesirable effects on asbestos or
whatever. In the field of DIY and building materials, I've learned to try
and avoid taking anything for granted.

JD

[Murmansk]

Take care if walking on an asbestos roof.

I used to be able to walk on my asbestos garage roof then, ten years later, I stepped on it and went straight through it and ended up inside the garage!

[Jim K]

> I think for �12 you may as well just have a go & see if it sorts the > problem?

That may be the thing to do, but I thought I'd ckeck first - in case, say, anyone has found the stuff to have undesirable effects on asbestos or whatever. In the field of DIY and building materials, I've learned to try and avoid taking anything for granted.

JD

End quote/

Judicious googling will alert you to any obvious pitfalls with a plan. Relying too much on stuff on here without further checks is inept if not stupid sometimes....
Jim K

[Cash]

Moral of the story here is *ALWAYS* use a duckboard when working/walking on
asbstos cement roofs (or similar, inc. corrugated steel ones) - whether new
or old!

It's a hell of a learning curve when you fall through one.;-)

Cash

[JakeD]

Murmansk <stai...@gmail.com> wrote in news:6dad0e8c-824a-424c-bf58-
5df2ba...@googlegroups.com:

> Take care if walking on an asbestos roof.

I do... I had to walk around on it a few months ago, to add some extra
roofing screws (with waterprorf washers). I was extremely cautious. But at
the end of the day, it seemed solid enough, despite the age of the sheets,
and I'm by no means lightweight. But as you rightly imply, the stuff is
going to get weaker with age, so caution is pretty much essential. When I
have to go up there, I try to tread close to where a joist is.

JD

[JakeD]

Jim K <jk98...@gmail.com> wrote in

news:9a718d0d-26d7-461c...@googlegroups.com:

> Judicious googling will alert you to any obvious pitfalls with a plan.
> Relying too much on stuff on here without further checks is inept if
> not stupid sometimes....

I agree.

JD

[JakeD]

JakeD <fgdf...@ghghfgh.com> wrote in news:XnsA2A3DFD8E2355aaaalifecom@
130.133.4.11:

PS...

However, I'd much rather pay heed to people's first-hand experience of a
product than the hype used by the advertiser/distributor/manufacturer to
sell the product! (Nosiree, things haven't changed much since the days of
'snake oil'!)

JD

[Jim K]

On Friday, December 27, 2013 10:39:35 PM UTC, JakeD wrote:

> However, I'd much rather pay heed to people's first-hand experience of a
>
> product than the hype used by the advertiser/distributor/manufacturer to
>
> sell the product! (Nosiree, things haven't changed much since the days of
>
> 'snake oil'!)

mmm by now I would have thought if someone had had your particular issue they would have contributed on one of your threads (if they were going to). Seems the answer is "we don't know but here are some theories" & for 12 quid - blaze your own trail!

Cross your fingers & let us know if it works or not.

If that's too much of a gamble I don't think you should be DIYing it. Get your cheque book out for a couple of hundred, pay a man (if one will touch it) and then er.. cross those same fingers ;>)

Jim K

[JakeD]

Jim K <jk98...@gmail.com> wrote in

news:256bbcb4-b992-48f1...@googlegroups.com:

> Cross your fingers & let us know if it works or not.
>
> If that's too much of a gamble I don't think you should be DIYing it.
> Get your cheque book out for a couple of hundred, pay a man (if one
> will touch it) and then er.. cross those same fingers ;>)
>
> Jim K

So, on the one hand you're saying "Relying too much on stuff on here
without further checks is inept if not stupid", and on the other you're
saying "Cross your fingers & let us know if it works or not."

> Seems the answer is "we don't know but here are some theories"

I don't have a problem with that. If you do, why waste your time in this
thread?

JD

[Jim K]

On Saturday, December 28, 2013 10:24:05 AM UTC, JakeD wrote:
> Jim K <jk98...@gmail.com> wrote in
>
> news:256bbcb4-b992-48f1...@googlegroups.com:
>
>
>
>
>
> > Cross your fingers & let us know if it works or not.
>
> >
>
> > If that's too much of a gamble I don't think you should be DIYing it.
>
> > Get your cheque book out for a couple of hundred, pay a man (if one
>
> > will touch it) and then er.. cross those same fingers ;>)
>
> >
>
> > Jim K
>
>
>
>
>
> So, on the one hand you're saying "Relying too much on stuff on here
> without further checks is inept if not stupid", and on the other you're
> saying "Cross your fingers & let us know if it works or not."

yes.

> > Seems the answer is "we don't know but here are some theories"
>
> I don't have a problem with that. If you do, why waste your time in this
> thread?

because I think you maybe a troll.

You start multiple threads with the same issue, last December being a good example, remember this?

"12/19/12
Hi all,

I have a double garage with a sloping 'big 6' corrugated asbestos roof
which is about 30+ years old. The roof joists are getting very wet in
places. At first I thought it must be due to rainwater getting in through
one or two of the holes through with the 6" galvanised roofing nails were
driven. However, after carefully sealing any possible such leaks, the
wetness continues. Yesterday (which was a cold but rain-free day), I went
into the garage and inspected the roof, just after nightfall, and I
discovered that almost the whole underside of the roof had a lot of
condensation on it. Since the roof is gently sloping, that condensation
runs along the enderide of each corrugation ridge, until it meets a joist.
That is where the water gets into the wood. One weird thing I noticed is
that some sheets of the asbestos seem more prone to condensation than
others.

Are there any tricks I can employ to stop the condensation?

If not, does anyone know of any way to divert the water away from the
joists? I thought of gluing a short length of string to the underside of
each ridge, just upward of each joist, so that the water drips down the
string and into the garage... but it's not a very satisfactory solution,
because I have a lot of perishable stuff stored in the garage.

Can anyone offer any suggestions?

Thank you...

JakeD"

Jim K

[JakeD]

Jim K <jk98...@gmail.com> wrote in

news:e97cb8c0-5844-4a27...@googlegroups.com:

> because I think you maybe a troll.
>
> You start multiple threads with the same issue, last December being a
> good example, remember this?

Get a life!
(...and welcome to my killfile.)

JD

[Jim K]

Suspect its not me that needs a life...

With an apparent grand total of 53 odd messages on usenet I am surprised you feel the need to have one....

or do you have other aliases like colonel scott, kruger etc?

ICM5£ ;>)

Jim K

[Bill]

On 28/12/2013 16:54, Jim K wrote:

> Suspect its not me that needs a life...
>
> With an apparent grand total of 53 odd messages on usenet I am surprised you feel the need to have one....

<PLOINK!> (...You just entered my bozo-bin, too!)

Jim

[Jim K]

grow up "Jake" & see you next christmas with the garage thread (again)

Jim K

[JD]

"Dave Liquorice" <allsortsn...@howhill.com> wrote in
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk:

> Foam isn't really the right stuff, from a can it's open not closed
> cell so water will get through it. As some one else said a good bead
> of exterior grade silicone along the edge of the sheet is probably
> you best bet, having cleaned/removed any loose material first.
>
> If the sheets are just nailed on is there any sealing washer under
> the nail heads?

Yes, all the nails and screws have plastic flexible washers, designed for
corrugated sheeting. Unfortunately, some of them are letting a tiny bit of
water past, which is allowing the joists to get damp.

I could cut the 7mm screws/nails off above the joist (very difficult, due
to tight access) and use a fresh screw and washer. However, being averse to
difficult jobs, I'd be interested in any other suggestions for affecting a
seal. I wondered about just plastering a good blob of silicone around each
washer, for example. Would that work okay?

JD