I`m about to re-point my detached brick garage and am seeking advice on the
correct mortar mix etc to use.

One of my neighbours did a similar job 4f years ago and some of his replacement
mortar is crumbling and coming out of the joints, especially around the lower
blue brick damp course.

Also is it wise to use PVA as a bond?

Thanks

Psfamilyhistory wrote:
I`m about to re-point my detached brick garage and am seeking advice on the
correct mortar mix etc to use.

One of my neighbours did a similar job 4f years ago and some of his replacement
mortar is crumbling and coming out of the joints, especially around the lower
blue brick damp course.

Also is it wise to use PVA as a bond?

I'm by no means an expert on the subject, but here's what's worked well
for me. Use a strong mix of soft sand and cement, around 3:1-4:1. Add
some integral water/frost proofer to your gauging water. Also add PVA to
the gauging water at about 25%. I find this gives a very nice, smooth
mix even at low water content.

Mix it fairly stiff, but wet enough so that the mix doesn't 'crack' when
handled.

Wet the area you're about to render/point, either with water or pref.
with 25% PVA.

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Grunff

Grunff wrote in message ...
Psfamilyhistory wrote:
I`m about to re-point my detached brick garage and am seeking advice on the
correct mortar mix etc to use.

One of my neighbours did a similar job 4f years ago and some of his replacement
mortar is crumbling and coming out of the joints, especially around the lower
blue brick damp course.

Also is it wise to use PVA as a bond?

I'm by no means an expert on the subject, but here's what's worked well
for me. Use a strong mix of soft sand and cement, around 3:1-4:1. Add
some integral water/frost proofer to your gauging water. Also add PVA to
the gauging water at about 25%. I find this gives a very nice, smooth
mix even at low water content.

Mix it fairly stiff, but wet enough so that the mix doesn't 'crack' when
handled.

Wet the area you're about to render/point, either with water or pref.
with 25% PVA.


If the building is made from soft brick, and lacks good foundations
and expansion joints, eg typical Victorian construction, then the mix
above should not be used, as it is likely to result in damaged and
broken bricks. So it does depend what you have. Victorian built
garages do exist, as do more modern soft brick ones, so I cant assume
this is not an issue.

Also the wall face should not be PVAed as it increases dampness in the
wall. But again, whether that is a real world issue depends on the
type of construction: for some it very much is, for some not.

For Vic walls 1:1:6 is commonly recommended.


Regards, NT

N. Thornton wrote:

If the building is made from soft brick, and lacks good foundations
and expansion joints, eg typical Victorian construction, then the mix
above should not be used, as it is likely to result in damaged and
broken bricks. So it does depend what you have. Victorian built
garages do exist, as do more modern soft brick ones, so I cant assume
this is not an issue.

Ok, fair point - I've only used the above on stone and concrete block.


--
Grunff

Grunff wrote in message ...
Psfamilyhistory wrote:
I`m about to re-point my detached brick garage and am seeking advice on the
correct mortar mix etc to use.

I'm by no means an expert on the subject, but here's what's worked well


Nor me; however, doesn't the nature mortar mix depend on factors like
the age of the building, type of bricks, how it was built in the first
place etc? My understanding is that, for example, if you use too hard
a mix than was intended, and/or which is impervious to water, you're
likely to cause severe future damage, isn't that right?

David

"Grunff" wrote in message


N. Thornton wrote:

If the building is made from soft brick, and lacks good foundations
and expansion joints, eg typical Victorian construction, then the mix
above should not be used, as it is likely to result in damaged and
broken bricks. So it does depend what you have. Victorian built
garages do exist, as do more modern soft brick ones, so I cant assume
this is not an issue.

Ok, fair point - I've only used the above on stone and concrete block.

In which case why use so much PVA it isn't an ingredient I've ever used
in mortar. If the brickwork is dry wait for damp weather and wet the
wall thoroughly then apply the mix. Make sure you have hacked out enough
depth to give a key. And wet the wall as you move along every time it
looks dry.

What is important is that the pointing dries slowly. That is why a
weakish mix is preferabe.

Another problem is using fairy liquid or similar in the mix. Use no
detergent. It will be stronger if you use no Feb or similar too neither.
Harder to work though.


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(Lobster) wrote in message . com...

Nor me; however, doesn't the nature mortar mix depend on factors like
the age of the building, type of bricks, how it was built in the first
place etc? My understanding is that, for example, if you use too hard
a mix than was intended, and/or which is impervious to water, you're
likely to cause severe future damage, isn't that right?


If the mortar is stronger than the bricks, and the building is prone
to movement, as Victorians are, the weakest links break... the bricks.
Much better to have the mortar break, thats easy to fix. Vics
generally have very soft bricks, little foundation and no expansion
jonits, hence movement is routine.

I'm sure there arent a lot of Vic garages about, but I have seen them.


Regards, NT

Michael Mcneil wrote in message
Another problem is using fairy liquid or similar in the mix. Use no
detergent. It will be stronger if you use no Feb or similar too neither.
Harder to work though.
I believe the *correct* amount of detergent actually makes a stronger mix.
Proprietary plasticisers, however, are not true detergents but very small
particle size salts.
IMO pva simply takes the guesswork out of the equation. How porous is the
surface, how wet does it need to be etc.

In article ,
N. Thornton wrote:
I'm sure there arent a lot of Vic garages about, but I have seen them.

They were called coach houses then. None of this French rubbish.

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*I don't know what your problem is, but I'll bet it's hard to pronounce

Dave Plowman London SW
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