These are some of the common questions we receive. If you have any other questions, please call or email us.

  • 1) Can I get an estimate over the phone?

    We prefer not to do estimates over the phone because of the nature of work we provide. Several factors affect your estimate and the amount of labour involved can be an important factor to your estimate.

  • 2) How long does it take to get an estimate?

    This depends on if we have to set up an appointment or if we are doing a ride-by estimate. If you set up an appointment, your estimate will be given to you at that time. If you are having a ride-by estimate done (where you are not present at the time of the estimate) we normally have these done within 10 days.

  • 3) What forms of payment does Perfect Glaze Ltd accept?

    We currently accept cash and check.

  • 4) Does Perfect Glaze Ltd do any financing?

    We currently do not do any financing. Please contact your financial institution for information regarding finance options for your home improvement projects.

  • 5) What is the difference between internal and externally glazed windows? Which do you recommend?

    Internally glazed windows have the glazing beads, which secure the double glazed unit in place, on the inside. Externally glazed windows have the glazing beads on the outside.From a security point of view most people would recommend internally glazed units, as it is not possible to remove the glass from the outside. However, using an externally glazed window with security tape on the inside of the glass, makes it virtually impossible to remove the glass directly from the outside.

    A wedge gasket system offers a similar security improvement. Again the wedge gaskets need to be removed from the inside before the external glazing beads can be removed. With an internally glazed system there is approximately 10mm extra of plastic (or aluminium) on each side of the sash, so you will have more glass and less plastic (or aluminium) on externally glazed windows. Transoms and mullions are usually welded with internally glazed pvc-u systems and mechanically fixed with externally glazed systems.

    For higher buildings with more than just ground and first floor, it is easier to fit internally glazed windows as most of the work is done from the inside. We do offer both options and can show you the difference when we come to see you.

  • 6) What is the best toughened glass or laminated glass? What is the difference? Is one more secure than the other?

    Toughened and Laminated glass are both what is known as 'Safety Glass'. It is normally (and indeed it must be) fitted in areas of danger such as doors, and windows close to the floor, where there is a danger of injury from falling against it. Both 'break safely'. Toughened glass is heated and cooled (tempered) during manufacturing which makes it harder to break than normal float glass. When it does break, it shatters into very small pieces which cannot cause serious injury. Laminated glass is actually two sheets of glass with a clear film sandwiched in-between. When this is broken it stays in place, still stuck to the inner film.

    Your new windows/doors should automatically have Safety Glass where it is legally required by Building Regulations. This will normally be toughened glass, which is cheaper to produce than laminated glass. It is not necessary to fit it elsewhere.

    Sometimes laminated glass is used for very large panes because it can be produced in larger sizes than toughened. Laminated glass is sometimes considered to be better purely from a security viewpoint because, although it breaks more easily, it stays in place.

    Bear in mind that if laminated glass is put into opening windows, or doors, it is much heavier than toughened glass and will produce much more 'wear and tear' on the hinges.

  • 7) What is the difference between u-pvc and pvc-u, one supplier claims better ageing, particularly colour, for pvc-u?

    There is no difference between u-pvc and pvc-u. Both terms refer to unplasticised (hard) pvc, which is used extensively in building products where rigidity is an important attribute.

    Plasticised (soft) pvc on the other hand is used where flexibility is important, for example medical tubing applications, insulation sheathing on electrical wiring, etc. Pvc-u is more to do with commonality of terminology worldwide than it is to do with formulation. Any claims of better performance of pvc-u over u-pvc are therefore spurious.

  • 8) What are the relative advantages of pvc-u versus aluminium for replacement windows?


    • Good insulator
    • Low maintenance
    • Many suppliers/usually the cheapest option today
    • Now available in wood grain and coloured finishes


    • Virtually no maintenance over its long lifetime
    • Slim, strong sections that will not warp or twist
    • About one third the expansion of pvc-u

  • 9) What is Secondary Double Glazing?

    Secondary glazing is another window fitted on the inside of your existing window, this is usually with aluminium with or without a hardwood sub-frame, it is some times called secondary windows. Secondary glazing can be used in addition to double glazing in particularly noisy areas, e.g. close to airport. It could also be used when existing windows are not to be replaced and are single glazed, e.g. in a listed building.

  • 10) I am looking for supply only, as my builder will be installing the windows in our extension. Is this possible?

    Whilst we prefer to supply and install, we are happy to do a supply only job.

  • 11) If we are replacing windows in our house I have heard that we need to apply for building regulations. Is this true?

    This is true and will typically cost you upwards of 200 Pound. However, if you use a FENSA registered company, such as You Choose, it is not necessary to apply for building regulations.

  • 12) What are equal sight lines?

    If you look at a double glazing installation and you cannot tell which are the openers and which are the fixed panes, then you're probably looking at equal sight lines.With equal sight lines you either have an opener or a dummy opener (dummy vent). This is an opening sash which doesn't open, so it's the same size as an opener. With non-equal sight lines the openers jut out more than the fixed panes.Aesthetically, equal sight lines look more pleasing to the eye, and you will get more plastic (or aluminium) and less glass.

  • 13) Will I need Planning Permission?

    In most cases you will not need planning permission, however we recommend that you check with your local planning office as each area is different.

    However the main reasons in which you may need planning permission are as follows:

    • If the conservatory is installed on the front of your home. No part of the conservatory should project further forward than the existing wall of the house facing onto a road
    • If your house has already been extended and by adding this conservatory the total added area exceeds 30 square meters
    • If you live within or near a conservation area
    • If your house is a listed building
    • If any part of the conservatory comes within 2 meters of the property boundary and is more than 4 meters above ground
  • 14) How often residential windows should be replaced?

    Homeowners with windows over 25 years old should consider replacing them, both to gain the best energy efficiencies and to protect the "envelope" of the house. A home is an ideal candidate for a window replacement if its windows are sealed or painted shut, experiences ice buildup or a frosty glaze during the winter, gets fogged with condensation or has drafts that come through the windows. For relatively new houses (less then 10 years) it depends on quality of windows installed by your builder. Some or our customers are not verky lucky and they starting to replace their windows in new housed after 5 - 7 years.

  • 15) What is Argon gas?

    Argon and other inert gasses also will reduce the loss of heat through an insulating glass unit. Since inert gasses are heavier than air, their molecules do not move as easily. This makes the space between the panes of glass in the window less conductive. Inert gasses between the two panes of glass make it more difficult for the warmer inside air to pass through the glass to the colder outside. With lower heat loss, the R-value is increased.

  • 16) What is LowE?

    The technical name of Low-E glass is actually Low-Emissivity, High-Transmittance, which means that Low-E reduces the amount of heat loss while still maintaining a high level of visible light coming through the glass. Low-E glass is one of the factors that determines the R-value, or insulation quality, of the glass. LowE glass has a metallic coating on the inside of the outside pane. The coating will help keep your house warmer in the winter and cooler in the summer. It also cuts down on the transmission of light slightly.

  • 17) How do I select type of glazing?

    Different climates and styles of homes require different glazing options to maximize their energy efficiency. Some glazing options can also help reduce outdoor traffic noise from entering the home. Options range from single glazed glass, as in historic homes (minimal insulating value), up to R10, which features dual-sealed, triple-insulated glass with two Low E surfaces and two krypton/argon gas-filled insulated airspaces for maximum efficiency.

  • 18) Why do windows sweat?

    Air is composed of several gases, one of which is moisture vapor. When air comes in contact with the Dew-point Temperature, the air is chilled and Condensation takes place with a residue of water on the surface of the glass.

  • 19) What is Single, double or triple glaze?

    Single glazing is a single pane of glass and is best used in garages and tool sheds buildings that don't need to be extremely energy efficient. Double-glazed windows have two panes of glass with either air or a safe, colourless and odourless gas tightly sealed between the panes. Double glaze is industry standard for residential houses and you probably will not find somebody who will offer you single pane windows. When its glass is treated with Low E coating, the window can achieve a value of R4 at the centre point of the glass. The most energy efficient window is a triple-glazed window. Gases are sealed between three panes of glass and Low E coatings are applied on two of the panes. This can bring the energy efficiency up to a value of R8 at the centre point of the glass.