Dee Verma
Hi Tony, you don't mention why this has been suggested, but it sounds unusual as i have been supplying windows and doors for over thirty years and it's the first i have heard this. What might be the case, is that you may have been approached by "flash harry in person" and he is just trying to impress you with words. A bit like some double glazing salesmen who want to be called a consultant. if you are looking to have your windows replaced call any company you like and they will come and advise you on designs and price the job. if you are happy with what they are offering and go ahead, they will send some one to come and measure the aperture and asses any problems that they are likely to encounter when they come to fit the windows this is know as conducting a survey of whats required for the job. Don't get confused with house survey because they are different and cost money - call them if you need them, but only if there is a structural issue and walls are being removed etc. A. window order that is being measured for production is often know as a survey and is ALWAYS FREE and YOU SHOULD NOT be paying for it, if they are charging you for it Walk Away. I'll come and do it for free.