Scratched windows revisited

[DeLaCruz]

Coming up to a year of water fed pole window cleaning and i oftenn leave jobs after closely inspecting the windows finding scratches. It leaves me feeling pretty bad - even though i havent had a single complaint (and also many compliments on my work). Still i am unsure of the validity of the technique for scratch free window cleaning. I clean a lot of south facing places where you can see clearly where the scratching occurs. I have come across many different opinions from window cleaners on the topic. I read through an old forum post on the topic: 

https://windowcleaningforums.co.uk/forums/topic/15108-water-fed-pole-scratched-glass/#comments

There are so many contradictory comments in this post it makes me wonder if anyone has done thorough testing. Many people think its almost impossible to scratch windows using WFP. However i have come across many scratch's in my first year after closely inspecting my work after cleaning. Seems like others also find these. I have gone through and found some example quotes: 

"Wfp can scratch glass , just had a new company under cut us on two jobs , took them 2 hours to clean a 5 bed house , destroyed three pains of glass and as told the customer to **** off when she rang them one day later

all because they wanted to save three pounds a month in there 4ook brand new house"

"I think people worry too much

I never rinse my brush..just a quick flick with my hand if it's got bit on it

Never scratched any glass

You would have to do something seriously wrong to scratch it like that."

"I have priced a couple of jobs up lately and the customers have asked if i use wfp as the last window cleaner had scratched the glass. When i looked at the 3 people that had said it there were lots of scratches on most of the glass. I could not think of any way this could have happened. But 3 people in different areas have said it has."

"But yeah if they were downstairs then I'd be very surprised if you didn't hear, see, or feel the scratching, so I'd say it's almost 100% not you mate"

"Personally i think that could be a contaminated brush. you don't have to push that hard with some sand to see a scratch and the flow of scratches, to me, looks like the path of movement made with a brush."

"A brush can be contaminated with grit when cleaning the door sill of french doors for example which are close to the ground. If you don't wash and get that out then you are carrying a potential to scratch glass on the next window you clean."

I clean many windows where there is dirt in the rubber seals. I can see how that would easily come out during the initial frame clean and contaminate a brush potentially causing scratching. It seems many window cleaners in the "You can't scratch windows using WFP" camp don't clean their brushes ever, laying them down on a pile of ground down diamond dust between cleans and never scratch windows!

"Sometimes I find I can spend as much time cleaning the brush as it does the window. I often stick my brush under a customers outside tap to clean it off between windows. Maybe this is why I'm so slow."

It is quite disconcerting that there is so much contradictory advice in this one thread from many experienced cleaners in one single thread. I have gotten to the point where is literally spend a great deal extra time and water pre rinsing every window (and rinsing my brushes as well) before i even clean the glass - and i am still finding scratches.

I am curious on how much testing has actually been done in to the lab to see how difficult it is to scratch windows with say a tiny bit of sand or grit on the brushes ? Often it is only visible from a certain angle with the sunlight shining on it, but it is still there for sure. Just looking to try and get some solid info on this subject so i can speed up and improve - thanks in advance as always ?

 

[ks789]

Coming up to a year of water fed pole window cleaning and i oftenn leave jobs after closely inspecting the windows finding scratches. It leaves me feeling pretty bad - even though i havent had a single complaint (and also many compliments on my work). Still i am unsure of the validity of the technique for scratch free window cleaning. I clean a lot of south facing places where you can see clearly where the scratching occurs. I have come across many different opinions from window cleaners on the topic. I read through an old forum post on the topic: 

https://windowcleaningforums.co.uk/forums/topic/15108-water-fed-pole-scratched-glass/#comments

There are so many contradictory comments in this post it makes me wonder if anyone has done thorough testing. Many people think its almost impossible to scratch windows using WFP. However i have come across many scratch's in my first year after closely inspecting my work after cleaning. Seems like others also find these. I have gone through and found some example quotes: 

"Wfp can scratch glass , just had a new company under cut us on two jobs , took them 2 hours to clean a 5 bed house , destroyed three pains of glass and as told the customer to **** off when she rang them one day later

all because they wanted to save three pounds a month in there 4ook brand new house"

"I think people worry too much

I never rinse my brush..just a quick flick with my hand if it's got bit on it

Never scratched any glass

You would have to do something seriously wrong to scratch it like that."

"I have priced a couple of jobs up lately and the customers have asked if i use wfp as the last window cleaner had scratched the glass. When i looked at the 3 people that had said it there were lots of scratches on most of the glass. I could not think of any way this could have happened. But 3 people in different areas have said it has."

"But yeah if they were downstairs then I'd be very surprised if you didn't hear, see, or feel the scratching, so I'd say it's almost 100% not you mate"

"Personally i think that could be a contaminated brush. you don't have to push that hard with some sand to see a scratch and the flow of scratches, to me, looks like the path of movement made with a brush."

"A brush can be contaminated with grit when cleaning the door sill of french doors for example which are close to the ground. If you don't wash and get that out then you are carrying a potential to scratch glass on the next window you clean."

I clean many windows where there is dirt in the rubber seals. I can see how that would easily come out during the initial frame clean and contaminate a brush potentially causing scratching. It seems many window cleaners in the "You can't scratch windows using WFP" camp don't clean their brushes ever, laying them down on a pile of ground down diamond dust between cleans and never scratch windows!

"Sometimes I find I can spend as much time cleaning the brush as it does the window. I often stick my brush under a customers outside tap to clean it off between windows. Maybe this is why I'm so slow."

It is quite disconcerting that there is so much contradictory advice in this one thread from many experienced cleaners in one single thread. I have gotten to the point where is literally spend a great deal extra time and water pre rinsing every window (and rinsing my brushes as well) before i even clean the glass - and i am still finding scratches.

I am curious on how much testing has actually been done in to the lab to see how difficult it is to scratch windows with say a tiny bit of sand or grit on the brushes ? Often it is only visible from a certain angle with the sunlight shining on it, but it is still there for sure. Just looking to try and get some solid info on this subject so i can speed up and improve - thanks in advance as always ?

 If I were you, try out on your own place. try and scratch a bit of window that you or ur mrs wont see. Bet you will find it damn difficult to scratch. A lot of these could be where builders etc have been trying to clear up and been heavy handed using unsuitable methods.

 

[Pjj]

Coming up to a year of water fed pole window cleaning and i oftenn leave jobs after closely inspecting the windows finding scratches. It leaves me feeling pretty bad - even though i havent had a single complaint (and also many compliments on my work). Still i am unsure of the validity of the technique for scratch free window cleaning. I clean a lot of south facing places where you can see clearly where the scratching occurs. I have come across many different opinions from window cleaners on the topic. I read through an old forum post on the topic: 

https://windowcleaningforums.co.uk/forums/topic/15108-water-fed-pole-scratched-glass/#comments

There are so many contradictory comments in this post it makes me wonder if anyone has done thorough testing. Many people think its almost impossible to scratch windows using WFP. However i have come across many scratch's in my first year after closely inspecting my work after cleaning. Seems like others also find these. I have gone through and found some example quotes: 

"Wfp can scratch glass , just had a new company under cut us on two jobs , took them 2 hours to clean a 5 bed house , destroyed three pains of glass and as told the customer to **** off when she rang them one day later

all because they wanted to save three pounds a month in there 4ook brand new house"

"I think people worry too much

I never rinse my brush..just a quick flick with my hand if it's got bit on it

Never scratched any glass

You would have to do something seriously wrong to scratch it like that."

"I have priced a couple of jobs up lately and the customers have asked if i use wfp as the last window cleaner had scratched the glass. When i looked at the 3 people that had said it there were lots of scratches on most of the glass. I could not think of any way this could have happened. But 3 people in different areas have said it has."

"But yeah if they were downstairs then I'd be very surprised if you didn't hear, see, or feel the scratching, so I'd say it's almost 100% not you mate"

"Personally i think that could be a contaminated brush. you don't have to push that hard with some sand to see a scratch and the flow of scratches, to me, looks like the path of movement made with a brush."

"A brush can be contaminated with grit when cleaning the door sill of french doors for example which are close to the ground. If you don't wash and get that out then you are carrying a potential to scratch glass on the next window you clean."

I clean many windows where there is dirt in the rubber seals. I can see how that would easily come out during the initial frame clean and contaminate a brush potentially causing scratching. It seems many window cleaners in the "You can't scratch windows using WFP" camp don't clean their brushes ever, laying them down on a pile of ground down diamond dust between cleans and never scratch windows!

"Sometimes I find I can spend as much time cleaning the brush as it does the window. I often stick my brush under a customers outside tap to clean it off between windows. Maybe this is why I'm so slow."

It is quite disconcerting that there is so much contradictory advice in this one thread from many experienced cleaners in one single thread. I have gotten to the point where is literally spend a great deal extra time and water pre rinsing every window (and rinsing my brushes as well) before i even clean the glass - and i am still finding scratches.

I am curious on how much testing has actually been done in to the lab to see how difficult it is to scratch windows with say a tiny bit of sand or grit on the brushes ? Often it is only visible from a certain angle with the sunlight shining on it, but it is still there for sure. Just looking to try and get some solid info on this subject so i can speed up and improve - thanks in advance as always ?

a scratch is basically a v in the glass acting as a prism and reflecting light , when dirty it’s difficult to see when clean it stands out like a soar thumb , I think most scratches are there before we start and show up after cleaning not before , it’s not scientific but years ago I deliberately tried to scratch old pains of glass with the stick of the brush to see if I could cause any damage , and yes you can but it’s not easy to do so just using a brush I think it would be very hard to do so unless you had something very sharp on the bristles 

 

[DeLaCruz]

 If I were you, try out on your own place. try and scratch a bit of window that you or ur mrs wont see. Bet you will find it damn difficult to scratch. A lot of these could be where builders etc have been trying to clear up and been heavy handed using unsuitable methods.

yeah i am aware that there is a lot of window cleaners who say builder scratch the glass up a lot, i have seen these scratches (usually around the outer edge of the glass where the frames were taped up and scraped off roughly).

However, that doesn't explain the some of the comments that say about WFP cleaning scratching glass. Also i find it really interesting there is such a huge divide in opinion about the maintenance of brushes on a day to day basis. If sand or dirt can scratch glass, and it collects in the rubber seals around the the window frames it stands to reason that the windows will get scratched if you properly clean the frames then the glass afterwards.

a scratch is basically a v in the glass acting as a prism and reflecting light , when dirty it’s difficult to see when clean it stands out like a soar thumb , I think most scratches are there before we start and show up after cleaning not before , it’s not scientific but years ago I deliberately tried to scratch old pains of glass with the stick of the brush to see if I could cause any damage , and yes you can but it’s not easy to do so just using a brush I think it would be very hard to do so unless you had something very sharp on the bristles 

yeah that's what i am thinking - it is a lot easier to scratch glass than the industry thinks. i use regularly rinsed brushes and a super high water flow rate these days to ensure the glass is pre rinsed before i even put a brush on it. It only takes a tiny grain of sand to scratch the glass - these are usually found in the seals of every coastal property around, this is making my day to day work much slower / more stressful. I want results i can be proud of but that is often not what i am seeing. 

 

[Pjj]

yeah i am aware that there is a lot of window cleaners who say builder scratch the glass up a lot, i have seen these scratches (usually around the outer edge of the glass where the frames were taped up and scraped off roughly).

However, that doesn't explain the some of the comments that say about WFP cleaning scratching glass. Also i find it really interesting there is such a huge divide in opinion about the maintenance of brushes on a day to day basis. If sand or dirt can scratch glass, and it collects in the rubber seals around the the window frames it stands to reason that the windows will get scratched if you properly clean the frames then the glass afterwards.

yeah that's what i am thinking - it is a lot easier to scratch glass than the industry thinks. i use regularly rinsed brushes and a super high water flow rate these days to ensure the glass is pre rinsed before i even put a brush on it. It only takes a tiny grain of sand to scratch the glass - these are usually found in the seals of every coastal property around, this is making my day to day work much slower / more stressful. I want results i can be proud of but that is often not what i am seeing. 

We do a lot of costal jobs like you some properties are on the beaches and covered in sand and seaweed and salt and are opaque when we clean them I can honestly say that evan after close inspection there arnt any scratches or if there are it’s certainly not from the cleaning process , some of the places we di di have damaged glass from being sand blasted in gales and stones hitting the glass there have been a few that have evan had the windows smashed in storms , I honestly think you are over thinking this , we have been doing this type of work for 20 years and never had a complaint Ime sure if damage was being done we would have had a few by now . Ime sure what you are seeing is a dirty window and not seeing the scratches then cleaning it and then you can clearly see the scratches as the v is clean and reflects the light , cleaning trad will also hide the scratches as the soap will stay in the v and stop it reflecting the light so it’s difficult to see any scratches , unless you are doing something drastically wrong I doubt you will scratch any glass , I have deliberately tried a number of times and unless you scrape the screws in the brush on the glass it’s very hard tk damage anything , next time you are down I’ll let you have a go and see if you can scratch some customers windows ???

 

[Bwfc]

Best idea to stop any scratching is to replace brush when necessary,  e.g. every 4, 6 or 12 months depending on brush life 

 

[Iron Giant]

Look at the same piece of glass from slightly different angles in different light and conditions will either show up scratches you have never seen before or a slight tilt of the head and they can disappear, the scratches you have seen will have no doubt always been there,

I pointed out a scratch to a customer on a porch window now this porch window is the size of a shop window and no doubt cost £1,000's and neither him or me could see it if we walked slightly forward or stood at different angle and in order to determine and inspect the glass to see if it was a scratch he had to stand still and direct me to it as it disappeared before my eyes as I stepped forward.

I will say that when a client has had building work done or a new patio laid I will rinse down the glass and frames very much like a first clean with a little extra caution if there appears to be building materials or cement on the glass, to avoid any risk of scratching the glass, but to do this on every regular clean is pointless and O.C.D and I have cleaned 100's of houses on developing new build estates without issue. 

 

[Skxawng]

It's both difficult and easy to scratch glass with a wfp brush.

It's pretty much impossible to scratch glass with the brush head as standard. Even if you had protruding brass jets they couldn't scratch glass. It's all to do with the hardness- things can only scratch other things that have a lower or equal hardness. Plate glass has a hardness on the Mohs scale of 5.5. Plastics, bristles and even brass are all below that. Sand though is mainly quartz which has a hardness of 7 so sand/grit if stuck in your bristles you could scratch glass easily with just light pressure.

It's still uncommon though as long as you have common sense like don't rest your brush head on the floor or against a wall.

Also remember it's actually less likely to scratch glass with WFP than trad. If you get grit in your applicator then it could stay in there for a long time, also a rubber squeegee can scrape grit along causing scratches. With a brush, even if there is some grit, it will most likely just flow away with the water, there's nothing keeping it in the bristles.

That's why companies like Pilkintons advise against using rubber Squeegees on self cleaning glass as they are more prone to scratching.

Basically, cleaning isn't an exact science and over years of weathering and cleaning glass will eventually start to show wear and tear but that's inevitable and it's not something you need to worry overly about as long as you're careful.

 

[DeLaCruz]

I'm sure what you are seeing is a dirty window and not seeing the scratches then cleaning it and then you can clearly see the scratches as the v is clean and reflects the light 

I did think this as well but the pattern of the scratches is really similar in many cases and i feels like the exact marks a brush would make. Maybe you could argue that is an assumption but i know the difference between scraper marks and brush marks. it literally is doing my head in bc i wanna do a thorough and blemish free job i am proud of  (but often walk away with a lump in my stomach awaiting a phone call complaining about the marks). 

I did wonder if it could possibly be to do with the initial frame clean and the following glass clean process. Could i be excatvating sand / grit fromt he frames onto the glass and then it contaminating my brush. I am now overly meticulous and careful with all my window frame cleaning, trying to not even put the brush n the glass until the glass have been rinsed off thoroughly and then the brush has been rinsed - that means i work rate is much slower than many people i a have worked with ( due to the amount of paranoid glass pre-rinsing and brush maintenance during cleans that i do. ) Moving forward it seem like a tedious way to work on a day to day basis.

Best idea to stop any scratching is to replace brush when necessary,  e.g. every 4, 6 or 12 months depending on brush life 

Yeah i use fresh new brushes and keep them clean- do any of you lot trim hairs when they get frayed and start protruding ?

It's both difficult and easy to scratch glass with a wfp brush.

It's pretty much impossible to scratch glass with the brush head as standard. Even if you had protruding brass jets they couldn't scratch glass. It's all to do with the hardness- things can only scratch other things that have a lower or equal hardness. Plate glass has a hardness on the Mohs scale of 5.5. Plastics, bristles and even brass are all below that. Sand though is mainly quartz which has a hardness of 7 so sand/grit if stuck in your bristles you could scratch glass easily with just light pressure.

It's still uncommon though as long as you have common sense like don't rest your brush head on the floor or against a wall.

Also remember it's actually less likely to scratch glass with WFP than trad. If you get grit in your applicator then it could stay in there for a long time, also a rubber squeegee can scrape grit along causing scratches. With a brush, even if there is some grit, it will most likely just flow away with the water, there's nothing keeping it in the bristles.

That's why companies like Pilkintons advise against using rubber Squeegees on self cleaning glass as they are more prone to scratching.

Basically, cleaning isn't an exact science and over years of weathering and cleaning glass will eventually start to show wear and tear but that's inevitable and it's not something you need to worry overly about as long as you're careful.

Thanks for the science man, its interesting to hear and also the comparison to trad it interesting to me (i actually thought trad was safer).

Here is a picture of a balcony i did - i had a clean brush and used it vertically - i noticed these scratches from below when the sunlight lighted them up - i can't imagine how else these kind of marks would be made to a window? They look really similar to the picture in this post https://windowcleaningforums.co.uk/forums/topic/15108-water-fed-pole-scratched-glass/ 

 

[Pjj]

I did think this as well but the pattern of the scratches is really similar in many cases and i feels like the exact marks a brush would make. Maybe you could argue that is an assumption but i know the difference between scraper marks and brush marks. it literally is doing my head in bc i wanna do a thorough and blemish free job i am proud of  (but often walk away with a lump in my stomach awaiting a phone call complaining about the marks). 

I did wonder if it could possibly be to do with the initial frame clean and the following glass clean process. Could i be excatvating sand / grit fromt he frames onto the glass and then it contaminating my brush. I am now overly meticulous and careful with all my window frame cleaning, trying to not even put the brush n the glass until the glass have been rinsed off thoroughly and then the brush has been rinsed - that means i work rate is much slower than many people i a have worked with ( due to the amount of paranoid glass pre-rinsing and brush maintenance during cleans that i do. ) Moving forward it seem like a tedious way to work on a day to day basis.

Yeah i use fresh new brushes and keep them clean- do any of you lot trim hairs when they get frayed and start protruding ?

Thanks for the science man, its interesting to hear and also the comparison to trad it interesting to me (i actually thought trad was safer).

Here is a picture of a balcony i did - i had a clean brush and used it vertically - i noticed these scratches from below when the sunlight lighted them up - i can't imagine how else these kind of marks would be made to a window? They look really similar to the picture in this post https://windowcleaningforums.co.uk/forums/topic/15108-water-fed-pole-scratched-glass/ 

View attachment 18142

There is no way you have done that with a brush , it has to be existing damage just look at the width of the mark 

 

[scottish cleaning service]

Are you positive the scratches are on the outside? As mine were actually inside the glass unit. Bricklayers or roughcasters always scratch the glass with their mortar sticking to the glass and sliding down and then hardening. My mate was discribing his self-build and he noticed all the scratches after the roughcaster had gone because they never covered the glass. I don't think any window cleaner has scratched glass but its the customers first port of call.

 

[wezza13]

Also, bits of grit get whipped up by the wind and this can cause, albeit very small, scratches.

 

[Iron Giant]

@DeLaCruz you either need a holiday or a day out with @Pjj ? you are really overthinking things and been ott , if that job in the photo is a 20 minute job just think how many minutes, hours, days and weeks there are in between each clean, they were either there before you started or been caused by the client one of there family or even a pet.

I'll remind everyone of Bic pen Lady (other pens are available) I pointed out some cement on her bay window which she deduced had come from the building work next door, this had been on there for weeks and she happily removed it with the end of the pen and was quite pleased with herself, my chin dropped to the floor at the scratches she made, but she was totally oblivious and I was left standing there in shock ?

 

[DeLaCruz]

Thanks for all the positive feedback - i am just gonna crack on whilst maintaining my brushes well and being pretty thorough with my rinsing. 

@DeLaCruz you either need a holiday or a day out with @Pjj ?

Yeah i am planning a day out down his way soon, got my sunglasses packed ??

I'll remind everyone of Bic pen Lady (other pens are available) I pointed out some cement on her bay window which she deduced had come from the building work next door, this had been on there for weeks and she happily removed it with the end of the pen and was quite pleased with herself, my chin dropped to the floor at the scratches she made, but she was totally oblivious and I was left standing there in shock ?

Yeah i definitely notice the scratches that others seem oblivious too haha

 

[Tango]

I went to a client yesterday, found the builder next door had put up a new dividing wall between gardens and left cement on this guys window. It was still wet so i managed to get it off (good thorough bristle flick through followed) however I ended up going round to speak with the builder concerned and explained to him that had he left it to dry, i wouldn't be able to remove that and that he needs to use soapy water ASAP to get rid of it.

He seemed okay about it but it was quite obvious that it was something he'd never thought about previously.

 

[Iron Giant]

Yeah i am planning a day out down his way soon, got my sunglasses packed ??

Most likely you will need your rain coat and fishermans friends ?