[Ged]

Hi All
the acid wash i use for helping clean drives  is 5% HCl. seem to work ok most of the time but does anyone know if you can get a more concentrated version and in fact if it is appropriate / legal to use /transport such. would be helpful to hear youre ideas, comments or experiences
 
regards 
 
ged

[Jake]

Ged

If you went to a good builders merchant, you probably could get a stronger brick acid, something like 9% and 11% used to be standard, don't know about now though.

If you take the necessary precautions when working with brick acid, you should have no problems, if it is for sale, it's legal.

[Kwackers]

I want to start using it as i have an oppurtunity to do a few builders cleans, but worried incase is discolours bricks.

[steve doyle]

I dont use it but ive heard not to use on stone built houses.
Also common to wet the brick first and then apply, it stops the brick absorbing the acid. and dont allow to dry.

[Jake]

Builders cleans don't usually involve cleaning brickwork?? That is normally organised by the Bricklaying contractor.

[Jake]

Generally, brick acid would not normally discolour bricks, used incorrectly however, and you can discolour mortar badly.

[Roger Oakley]

Hi All
the acid wash i use for helping clean drives  is 5% HCl. seem to work ok most of the time but does anyone know if you can get a more concentrated version and in fact if it is appropriate / legal to use /transport such. would be helpful to hear youre ideas, comments or experiences
 
regards 
 
ged

Yes you can get stronger Hydrochloric acid Ged, I use 32% and dilute down as needed.

[Roger Oakley]

Generally, brick acid would not normally discolour bricks, used incorrectly however, and you can discolour mortar badly.

Depending on the strenght of the acld, you can also burn the face of the brick used incorrectly.

[allyoops]

From Jakes comment I would be interested to know how you can damage the mortar,and is it correct that you should wet the bricks before applying the brick acid,seems to me that that is just diluting the acid even more,cheers Neil

[Jake]

Neil

Brick acid attacks the cement. I have seen people throw a bucket of brick acid straight onto dry brickwork!!!! The damage to mortar joints is permenant, and has to be repaired.

Yes, it is wise to soak brickwork first, then there is not a dry area for the acid to 'burn', if you know what I mean.

[Andy Foster]

Applying acid to dry brickwork would get you kicked off most building sites as it not only can damage the surface of the mortar, it can soak in and ariate the mortar further in which can weaken it.
The brickwork MUST be wet when the acid is applied to avoid any possibility of this happening.

The less acid you can use that better however.  The safest and most ecological method is to pressure wash the brickwork (once the mortar has cured according to the manufacturers specification and at the correct pressure - vital if the NHBC cover that site), then only apply acid where necessary.

Acid would not normally affect the colour of bricks, but if there is any concrete blockwork then tests should be done to establish the correct acid and concentration to use otherwise it may discolour them.

All H&S, COSSH and method statements etc should be done of course and a copy given to the customer.  All PPE necessary should be provided by you (if you are the employer) to any staff either applying the acid or working in the vicinity.

If there are other people working anywhere near, then they should be offered PPE and warned of the possible hazards.

All of the above applies regardless of the concentration of the acid used.

Quite why you would want to apply acid to block paved drives I am not sure, but if it works for you then so be it.

[steve doyle]

"Quite why you would want to apply acid to block paved drives I am not sure, but if it works for you then so be it."

Good point andy, slipped under the rader there,


What are you cleaning and why the need for acid?

steve

[Roger Oakley]

Acids do have there place in cleaning, just depends on what you are trying to remove. Couple of things to remember though, if you are using an acid pre-wet/dampen the surface first. Make sure you are using the right acid for the right surface or damage can and will accure. Wear the correct PPE. If you take these rules as your standard then you should not have any problems.

[Andy Foster]

Hi Roger

Coudl you tell me what you would be trying to remove from a block paved driveway with acid?
I am interested in this because I have never needed to do this and if I am missing a trick then I would be grateful of your experience.

Thanks

Andy

[Roger Oakley]

Hi Roger

Coudl you tell me what you would be trying to remove from a block paved driveway with acid?
I am interested in this because I have never needed to do this and if I am missing a trick then I would be grateful of your experience.

Thanks

Andy

Andy,
Personally I very rarely use Hydrochloric acid on block paving, I have had to use it to remove cement staining where the home owners have had some building work done , and the builders have messed up their drive etc and left concrete residues on the surface. My original answer to Ged, was yes you can get stronger then the 5% brick acid that he is using, what he is using it for I don't know. If he is using it as part of a mainternace clean on a block drive, then I feel it is a waste of time and money using  Hydrochloric acid at any strengh. There are other chemicals for mainternace cleaning.

[Andy Foster]

OK, thanks.

Maybe Ged will let us know then.

Can I ask you why the use of any chemicals would be used, even for maintenance cleans though.  It seems an unecessary release of chemical to me, but like I said before, if I am missing a trick then I would be grateful of any advice.

Thanks

Andy

[Ged]

ok
acid wash uses

1. to remove efflorecence
2. to remove mortar staining
3 to soften the ingrained lichen stains that appear on the chamfers of block paving and so facillitate cleaning without mega pressure
4 it seems to help remove rust staining in some cases.

if you more experienced guys know better ways of doing this i'm always willing to learn

regards

Ged

[Roger Oakley]

ok
acid wash uses

1. to remove efflorecence
2. to remove mortar staining
3 to soften the ingrained lichen stains that appear on the chamfers of block paving and so facillitate cleaning without mega pressure
4 it seems to help remove rust staining in some cases.

if you more experienced guys know better ways of doing this i'm always willing to learn

regards

Ged

Ged,
To answer your uses of Hydrochloric acid,
1. to remove efflorecence, yes try a 8-10% strength.
2. to remove mortar staining, Yes again start at the above strength, you might need  make a stonger mix depends on what you are trying to remove.
3 to soften the ingrained lichen stains that appear on the chamfers of block paving and so facillitate cleaning without mega pressure, No waste of time, plus you could damage the surface of the paver, You don;t usually need an acid on block paving if the dirt/stain is organic. I think I have answered this question for you via email before Ged as to what to use.
4 it seems to help remove rust staining in some cases. Ged, again I answered this question via an email.

[Roger Oakley]

OK, thanks.

Maybe Ged will let us know then.

Can I ask you why the use of any chemicals would be used, even for maintenance cleans though.  It seems an unecessary release of chemical to me, but like I said before, if I am missing a trick then I would be grateful of any advice.

Thanks

Andy

Andy,
All my washes are chemical based, does the job far better then pressure alone.
You may think it is an unnecessary use, but it works, the  least pressure on the surface can equal least damage. Look at it this way, do you wash your dinner plates in water only? your car/truck? your laundry? no you have to have/add something to get the above clean, detergent, soap etc, I view what I do in the same way, water alone is not enough.

[Andy Foster]

I totally understand your thinking behind the whole 'use detergent to wash hands and not just water' scenario and in certain circumstances, I agree there is a need for the use of chemicals.
I too use chemicals, when all other options have been examined.

However, to justify the use of chemicals to clean drives that could be cleaned perfectly well using just water (and in my opinion just as well as with chemicals) by stating that it creates less wear on the blocks is not a well thought out argument.

The long term damage of pressure washing to the blocks is neglegible, especially if the operator is experienced. However the long term damage to the customers land/soil/garden whatever you want to call it by the use of chemicals is more than likely to be quite significant.

I don't want to get into an in depth discussion about this and was just asking the question originally to see if there was some trade secret that had evaded me for all this time... it appears not.

If that is the method you wish to use then of course I have to respect that and know that your results are excellent Roger as can be seen on your website, however, if there is anyone reading this who is wondering which course to take, then I just ask that you think of the damaging effects of chemicals on the environment before pursuing that particular avenue.

Please do not get me wrong (as so often happend to people in this forum), I am not picking an argument with anyone here, I am simply expressing my opinions on a subject I feel strongly about.
Roger is very giving of his knowledge and I have respect for him and his business.

[steve doyle]

Hmmm, interesting one this,

I have to agree andy, I clean using water only, the results i get surpass the expectations of the customer which is what i am interested in along with the ease of the job . Routine chemical or detergent additions seem unnessacery and add a risk factor.

I am not "anti chemicals" as it were but once or twice a year for a specific problem would be about the frequency i would need them.

As for damage from water pressure or chemicals I believe water pressure damage is less likely, easier to spot occuring and quickly stopped. Chemical damage is hard to spot when occuring and difficult to stop once its started. There is also plants, pets etc and the run off to consider.

The safety issue with chemical use plus the gain really makes me feel they are not worth the aggrivation for routine use.

[Roger Oakley]

 Chemical damage is hard to spot when occuring and difficult to stop once its started. There is also plants, pets etc and the run off to consider.

Not if you know what you are doing.

[Andy Foster]

Absolutely right Roger, unfortunately not everyone does know what they are doing, which is where the problems can occur.

However, the question isn't about competence, it is about the need to use chemcials when water would do a perfectly good job.

We all have our own opinions and ethical stance on chemical use (and indeed we are all entitled to them).

Thanks for the open discussion.

Andy

[steve doyle]

 Chemical damage is hard to spot when occuring and difficult to stop once its started. There is also plants, pets etc and the run off to consider.

Not if you know what you are doing.

While i appreciate where your coming from with this, I feel that my statement was accurate.

1, Chemical damage is harder to spot occuring than pressure damage because it is rarely occurs instantly and you can be working on another area of job when signs become visable.

2, Any discoloration can be difficult to spot or not always visable untill dry.

3, If damage does occur with chemicals, you cannot stop it instantly unlike the trigger on a gun.


If your "not if you know what your doing" reply refers to not making an error in the first place then all well and good, I am simply suggesting that for those of us that have ever made a mistake or may well in the future It can create alot of aggrivation and heart ache.


The potential problems combined with neglible "routine job" improvements mean i am not prepared to use chemicals unless to resolve a specific problem.

I Think people obviously make their own decisions about best practise as this thread demonstrates but for those people who are novices to this field i would like to displace any myth that routine chemical use is the norm or compulsary.

[Roger Oakley]

Absolutely right Roger, unfortunately not everyone does know what they are doing, which is where the problems can occur.

However, the question isn't about competence, it is about the need to use chemcials when water would do a perfectly good job.

We all have our own opinions and ethical stance on chemical use (and indeed we are all entitled to them).

Thanks for the open discussion.

Andy

Andy sensible reply it was an open discussion.

[Roger Oakley]

 Chemical damage is hard to spot when occuring and difficult to stop once its started. There is also plants, pets etc and the run off to consider.

Not if you know what you are doing.

While i appreciate where your coming from with this, I feel that my statement was accurate.

1, Chemical damage is harder to spot occuring than pressure damage because it is rarely occurs instantly and you can be working on another area of job when signs become visable.

2, Any discoloration can be difficult to spot or not always visable untill dry.

3, If damage does occur with chemicals, you cannot stop it instantly unlike the trigger on a gun.


If your "not if you know what your doing" reply refers to not making an error in the first place then all well and good, I am simply suggesting that for those of us that have ever made a mistake or may well in the future It can create alot of aggrivation and heart ache.


The potential problems combined with neglible "routine job" improvements mean i am not prepared to use chemicals unless to resolve a specific problem.

I Think people obviously make their own decisions about best practise as this thread demonstrates but for those people who are novices to this field i would like to displace any myth that routine chemical use is the norm or compulsary.

Steve,
You may feel you statement was accurate,
But here are my answwers to your 3 points
1, I suggest you all do some research, learn what chemicals really do.
2, You can neutralise a chemical if you know what you are doing, see staement one.
3, Chemical damage can be visible straight away if you know what you are looking for, unlike an etchced surface, which can sometimes only be seen when the surface is dry.

I don't know what you do, but we only pressure wash, be it decking, paving, building washes etc 52 weeks, 12 months of the year so I think I know what works, I have enough of you guys email or phone me for advice.

Anyway don't really want to get into a big debate with this subject as we will all have our own opinions , I will say this, do some research on this, do some tests, you might learn something.

[steve doyle]

Well roger I Also pressure wash full time.

Having worked for 5 years for chemical manufacturers I understand what chemicals do and how they work thank you.

Without this becoming an argument your condescending responce didnt actually address any of the 3 points i made.

 1, Chemical damage is harder to spot occuring than pressure damage because it is rarely occurs instantly and you can be working on another area of job when signs become visable.
" I suggest you all do some research, learn what chemicals really do."
()

2, Any discoloration can be difficult to spot or not always visable untill dry.
" Chemical damage can be visible straight away if you know what you are looking for, unlike an etchced surface, which can sometimes only be seen when the surface is dry."
(yes they can be visable straight away but often are not as per my statement 2. chemicals invariably take time to work).


3, If damage does occur with chemicals, you cannot stop it instantly unlike the trigger on a gun.
" You can neutralise a chemical if you know what you are doing, see staement one."
(yes you can neutralise chems but it takes time, its not instant and can take several minutes as point 3!)

Personally it bothers me not one jot what you choose to use and how, nor will i try to suggest you should do anything different as its of no interest for me to do so. if you do feel the need to question the acuracy of my posts feel free but please do it factually.

I will end my involvement in this thread now but you do make a very good point that its always important to research the chemicals you are going to use and continue learning.

steve

[Roger Oakley]

Steve
Sorry if you thought my response was condescending, it wasn't meant to come across that way.  I think the "what is the best ways to clean" debate could run on forever, so best everyone do what works for them really. You are right Steve it is now a good time to end this thread/debate.