Waves or Ripples

[RFC Bear]

1st post, so be gentle with me .
My brother in law, is in the process of having a new Conservatory build, it has 12 double glazing units.
8 of these are perfect but 4 have really bad, waves or ripple effect on them.
The owner of the firm building the Conservatory, has said this quite common and there is nothing he can do, as it down to the way the glass is made.
He also says this common knowledge in the double glazing industry but is just never mentioned.
After much dialog between them, my brother in law seems to be accepting of this explanation.
I don’t know anything about glass but surely that can’t be right, should the 4 windows not be replaced?
Any comments would be greatly appreciated.

 

[Scrit]

I thought that the whole point of float glass is that it is optically "correct". Or have I got that wrong?

Scrit

 

[masona]

Depends how bad it is, if it's that bad, they should replace them.

 

[RFC Bear]

Depends how bad it is, if it's that bad, they should replace them.

Thanks for your replies, to my eye and most of the rest of the family, they are bad.
I placed a big orange bucket between one of the good windows and a rippled one, the half reflection on the good window is perfect but on the other one, the bucket has a concertina effect.
you can also notice it walking toward them.
Funnily enough you only notice looking in , not looking out.

The owner of the firm is not for shifting, although he has not been paid yet but we wanted to be sure of the facts before taking it any further.

 

[Scrit]

I thought that DG units had to be manufactured using Pilkington K-glass or a similar float glass. One of the plusses to Pilkington's float process is that it produces glass which is optically flat - so you don't get ripples in it. Just what have the glazing firm used if it's not flat?

I found a quote from a consultancy called Tangram, "Float glass is produced by floating a continuous stream of molten glass onto a bath of molten tin. The molten glass spreads onto the surface of the metal and produces a high quality, consistently level sheet of glass that is later heat polished. The glass has no wave or distortion and is now the standard method for glass production and over 90% of the world production of flat glass is float glass."

Scrit

 

[RFC Bear]

I thought that DG units had to be manufactured using Pilkington K-glass or a similar float glass. One of the plusses to Pilkington's float process is that it produces glass which is optically flat - so you don't get ripples in it. Just what have the glazing firm used if it's not flat?

I found a quote from a consultancy called Tangram, "Float glass is produced by floating a continuous stream of molten glass onto a bath of molten tin. The molten glass spreads onto the surface of the metal and produces a high quality, consistently level sheet of glass that is later heat polished. The glass has no wave or distortion and is now the standard method for glass production and over 90% of the world production of flat glass is float glass."

Scrit

Thanks for your help Scrit.
I passed your comments on and my brother in law spoke to the owner this morning.
He has now agreed to replace the 4 windows, only after my brother in law threatened to keep 20% of the bill until it was resolved.
He was still going along the line that this is common and is something to do with baking the glass last.
Anyway that is it sorted.
Thanks again

 

[Richard C]

I would definately reject them, they should be optically perfect; after all it's a conservatory you've bought not a house of funny mirrors! You really need to clarify what type of windows, glass & roof is being used for a conservatory BEFORE accepting the quote. These are are not yet subject to BC so they don't have to follow the same standards with regard to heat loss, frame construction & air gap with the result that some companies use inferior units to keep the cost down & profit up! I had a new conservatory put up last year & insisted on units with a 20mm air gap & Pilkington 'K' glass, the same standard required for houses etc.

 

[Glassman]

The glass can sometimes distort when it goes through the Toughening process which your units probably are? If you aren't happy though, I dont see why he wont change them.

I've worked on quite a few factory refurb jobs in the past where I've had to glaze Restoration glass into very old steel windows to give an old fashioned distorted appearance.

For the record, Restoration glass is very expensive compared to ordinary float glass and the more distorted and rippled it is, the better.
If this guy was using the cheapest glass available to him, it wouldn't be rippled glass.

 

[Scrit]

He was still going along the line that this is common and is something to do with baking the glass last.

One of my stepbrothers used to be a toughener at Pilkingtons in St. Helens and his comment when I mentioned this to him was that if they got a ripple in glass as it went through then the entire piece went to the cullet skip, so the manufacturer used to set a high standard at one time.

Scrit