Hi all

Not posted on here for a couple of years - but had loads of help when I
did... so thanks....

I'm here this time to understand 'render'. I ecently had a wall of a barn
'tyrolean' rendered. Seems ok - but got a few hairline cracks - is that to
be expected?

I've just had a company out to quote on sorting out the gable ends &
chimneys - and they use a product made by Renotex - a breathable resin
render.

Has anyone got anything good or bad to say about it?

Thanks in advance

Simon

On Sep 27, 7:13 pm, wrote:
Hi all

Not posted on here for a couple of years - but had loads of help when I
did... so thanks....

I'm here this time to understand 'render'. I ecently had a wall of a barn
'tyrolean' rendered. Seems ok - but got a few hairline cracks - is that to
be expected?

I've just had a company out to quote on sorting out the gable ends &
chimneys - and they use a product made by Renotex - a breathable resin
render.

Has anyone got anything good or bad to say about it?

Thanks in advance

Simon


Hi Simon,
'tyrolean' render is old hat now. It has a very bad press. So many
cowboys simply hired a gun (a fiver a day or so) and used it to spit a
bad mix over untreated walls.

It is essential that all cracks are remidied a week or so before the
aplication. If yours has cracks in it then you are in for trouble as
the rain will penetrate the affected areas and once under the coating
it has nowhere to go other than straight through to the iner walls or
straight down, both are not nice.

Good luck, Roy

On 27 Sep, 19:13, wrote:
Hi all

Not posted on here for a couple of years - but had loads of help when I
did... so thanks....

I'm here this time to understand 'render'. I ecently had a wall of a barn
'tyrolean' rendered. Seems ok - but got a few hairline cracks - is that to
be expected?

I've just had a company out to quote on sorting out the gable ends &
chimneys - and they use a product made by Renotex - a breathable resin
render.

Has anyone got anything good or bad to say about it?

Thanks in advance

Simon


Resin AND "breathable"? Sounds like a contradiction in terms....
What is wrong with a normal lime render? It has been used for some
thousands of years...?
chris

Resin AND "breathable"? Sounds like a contradiction in terms....
What is wrong with a normal lime render? It has been used for some
thousands of years...?
chris


I thought that a couple of years ago - which is why I went for the
traditional tyrolean render on the barn (the cracks are hairline). I've
checked out the web pages of the company that makes this resin render - and
it would appear to be breathable (it is not resin as used in the
construction of canoes). Not being an expert I'd suspect it does the same
job as gore-tex does with clothes....

Si

On 28 Sep, 06:40, wrote:


Resin AND "breathable"? Sounds like a contradiction in terms....
What is wrong with a normal lime render? It has been used for some
thousands of years...?
chris

It depends on how you define 'breathable' and how you define 'resin'.
There are ranges of very successful roof and wall coatings that have a
high vapour permeable rate. There are a range of such coatings for
roofs, walls etc. A lot of them are based on PU & PVA Resins

Merryterry wrote:
On 28 Sep, 06:40, wrote:

Resin AND "breathable"? Sounds like a contradiction in terms....
What is wrong with a normal lime render? It has been used for some
thousands of years...?
chris

AFAICS what's wrong with it is the rain will come and wash it off if
it's not protected with "damp sacking" for several weeks. My plasterer
doesn't seem to be interested for some reason

It depends on how you define 'breathable' and how you define 'resin'.
There are ranges of very successful roof and wall coatings that have a
high vapour permeable rate. There are a range of such coatings for
roofs, walls etc. A lot of them are based on PU & PVA Resins

The problem with all coatings is that any gap in the film can admit
large amounts of rainwater, which cannot then escape by the same route.
However breathable the film is, the imbalance between pouring in and
breathing out is too great.

On 28 Sep, 15:06, Stuart Noble
wrote:
Merryterry wrote:
On 28 Sep, 06:40, wrote:

Resin AND "breathable"? Sounds like a contradiction in terms....
What is wrong with a normal lime render? It has been used for some
thousands of years...?
chris

AFAICS what's wrong with it is the rain will come and wash it off if
it's not protected with "damp sacking" for several weeks. My plasterer
doesn't seem to be interested for some reason

It depends on how you define 'breathable' and how you define 'resin'.
There are ranges of very successful roof and wall coatings that have a
high vapour permeable rate. There are a range of such coatings for
roofs, walls etc. A lot of them are based on PU & PVA Resins

The problem with all coatings is that any gap in the film can admit
large amounts of rainwater, which cannot then escape by the same route.
However breathable the film is, the imbalance between pouring in and
breathing out is too great.

There are flexible resin coatings on the market that will withstand
some substrate cracking. They do need some care in application and the
correct 'bond break' primer, (i.e. a primer whose coating to primer
adhesion is less than the tensile strength of the coating) It will
then disbond rather than tear in the event of cracks appearing in the
substrate. They do not need weeks of damp sacking over them.

Try:

http://www.flexcrete.com/pdf/technic...DS_Decadex.pdf

I used to sell this product 15 years ago and it is first class. They
no longer use Sales Agents so I lost the agency.

Merryterry wrote:
On 28 Sep, 15:06, Stuart Noble
wrote:
Merryterry wrote:
On 28 Sep, 06:40, wrote:
Resin AND "breathable"? Sounds like a contradiction in terms....
What is wrong with a normal lime render? It has been used for some
thousands of years...?
chris
AFAICS what's wrong with it is the rain will come and wash it off if
it's not protected with "damp sacking" for several weeks. My plasterer
doesn't seem to be interested for some reason

It depends on how you define 'breathable' and how you define 'resin'.
There are ranges of very successful roof and wall coatings that have a
high vapour permeable rate. There are a range of such coatings for
roofs, walls etc. A lot of them are based on PU & PVA Resins
The problem with all coatings is that any gap in the film can admit
large amounts of rainwater, which cannot then escape by the same route.
However breathable the film is, the imbalance between pouring in and
breathing out is too great.

There are flexible resin coatings on the market that will withstand
some substrate cracking. They do need some care in application and the
correct 'bond break' primer, (i.e. a primer whose coating to primer
adhesion is less than the tensile strength of the coating) It will
then disbond rather than tear in the event of cracks appearing in the
substrate. They do not need weeks of damp sacking over them.

Try:

http://www.flexcrete.com/pdf/technic...DS_Decadex.pdf

I used to sell this product 15 years ago and it is first class. They
no longer use Sales Agents so I lost the agency.


Looks like it's based on SBR. I don't really trust water based
formulations when it comes to water resistance

On 28 Sep, 15:57, Stuart Noble
wrote:


Looks like it's based on SBR. I don't really trust water based
formulations when it comes to water resistance

Water Based formulations are perfectly OK for waterproofing. Water is
only the carrier for the resin. I can quote hundreds of applications
where I got Water Based Coatings specified and still all OK after many
years. One that springs to mind is Shelton Water Tower at Shrewsbury.
(on the old A5).

Merryterry wrote:
On 28 Sep, 15:57, Stuart Noble
wrote:

Looks like it's based on SBR. I don't really trust water based
formulations when it comes to water resistance

Water Based formulations are perfectly OK for waterproofing. Water is
only the carrier for the resin.

It's the things that have to be added to the resin for water to act as a
carrier that are the concern. They end up in the finished film, making
it more (if only fractionally) water sensitive.
ISTR acrylics are very fussy about temperature and normally require 20
degsC to cure properly. Fine in a controlled environment but a bit hit
and miss outdoors I would think. Maybe things have moved on since I last
had reason to look at all this.




I can quote hundreds of applications
where I got Water Based Coatings specified and still all OK after many
years. One that springs to mind is Shelton Water Tower at Shrewsbury.
(on the old A5).

On 30 Sep, 16:09, Stuart Noble
wrote:

ISTR acrylics are very fussy about temperature and normally require 20
degsC to cure properly. Fine in a controlled environment but a bit hit
and miss outdoors I would think. Maybe things have moved on since I last
had reason to look at all this.

Water based resin coatings will cure at well below 20C but just take
longer and need protecting from elements whilst curing. Most will cure
down to about 5C.

Merryterry wrote:
On 30 Sep, 16:09, Stuart Noble
wrote:

ISTR acrylics are very fussy about temperature and normally require 20
degsC to cure properly. Fine in a controlled environment but a bit hit
and miss outdoors I would think. Maybe things have moved on since I last
had reason to look at all this.

Water based resin coatings will cure at well below 20C but just take
longer and need protecting from elements whilst curing. Most will cure
down to about 5C.



The minimum film forming temperature (MFFT) of all but the softest
resins is nearer 20, or at least it was last time I looked.
The reason most acrylic gloss paint is soft and rubbery is that a harder
resin would need a higher temperature to cure properly.