Frequently Asked Questions

How to assemble a flat packed Residential Sliding Door?

 Watch this video on the exact steps showing you how to assemble a flat packed Residential Sliding Door:

How to assemble a flat packed Residential Stacking Door?

 Watch this video on the exact steps showing you how to assemble a flat packed Residential Stacking Door:


How to install a Fly Door Screen Latch?

Watch this video for a step by step process on how to assemble and attach the fly screen door latch:


Useful Forms and Templates to download:

Routine Care – GEM Windows and Doors

Care and maintenance

Hand Cleaning SmartGlass

Does GEM WINDOWS & DOORS do installation?

No, we specialise in supply only of aluminium windows and doors. Because we stick to what we know best, we are able to supply windows and doors to the retail customer at wholesale prices enabling you to save on the overall cost of your project when it comes to windows and doors. Our windows and doors are very easy to install and can be done by any licensed and qualified builder or carpenter with window and door experience.

Does GEM WINDOWS & DOORS do re-glazing or supply glass only or any mechanical parts for windows and doors?

No, we specialise in supply only of fully assembled and pre-glazed aluminium windows and doors.

Does GEM WINDOWS & DOORS provide quotations straight from the plans?

No, we only supply quotations based on complete windows and door schedules, where colour, glazing, reveals and any other details are clearly stipulated. We do not provide quotes from plans or scale to size.

What is the standard lead time on aluminium windows and doors from GEM?

The standard estimated lead time for our aluminium windows and doors changes depending on current work load and is always approximate, you will need to check current standard lead times with the showrooms prior to placing order. We strive to deliver our products before or on the deadline. We normally do not hold any stock as all windows and doors are made to order.

What is the maximum door height GEM can do?

The maximum door height we can offer is 2400mm. The standard door height we offer is 2095mm.

What are the colours GEM has on offer?

We have a standard range of 8 colours that can be viewed under our Standard or Custom range products. We can also do any other colour from the Interpon colour chart, however custom colours attract an approximately 45% surcharge and may result in longer lead time.

What different kinds of glass can GEM WINDOWS & DOORS provide?

The following list provides the names and features of the various types of glass that GEM Windows can supply with its windows and doors.

  • Single Clear Float Glass (4, 5 or 6mm)
  • Single Toughened Safety Glass (4,5 or 6mm)
  • Laminated Safety Glass (6.38)
  • Smart Glass (for Energy Efficiency)
  • VLAM Hush Glass (for Noise control)

Can standard size windows or doors be changed by a couple millimetres?

No, unfortunately that would defeat the purpose of the standard size range. The reason our standard size products can be offered to the retail clients at such good prices is through lean production and previously calibrated processes. Once you change the product even by a millimetre, this adds to the production cost, labour costs and other factors which results in a higher price of the product.

In most cases, it is possible to use slightly smaller sizes for the existing opening, your builder or installer should know what is required to make the standard size item fit.

Can I make changes to my order once it has been placed?

No, once orders are place changes cannot be made to the order.  The reason for this is that when an order is placed it is allocated a production date and all aluminium material, glass and all other products require to manufacture items are ordered to suit each specific job.  All products ordered from GEM Windows are made to order and no items are kept in-stock

This information is listed in Terms & Conditions:

1.    All items are made to order.  Windows and doors are non-refundable 2.    Alterations are not accepted after acceptance of the quote or invoice.  Your signature verifies your acceptance of the invoice or quote.

What is thermally improved aluminium?

Aluminium improved windows are aluminium frames that surpass a particular point of energy efficiency (amount of light let in and heat gain/loss.) Our standard Series 100 frames are “thermally improved’.

An aluminium improved frame is defined as one with a U-value of 8.0 W/m2.K or less. This may be achieved by a variety of design improvements, some (or all) of which may be present. Therefore a U-value of 8 or less, derived from a WERS rating, shall be the sole criterion for classifying a window as ‘thermally improved’.

What are the differences between aluminium frame sizes and stud sizes?

  • Aluminium frame size refers to the overall size of the aluminium frame of the window or door.
  • Stud sizes refer to the overall size of the aluminium frame coupled with the addition of the timber reveals.

When viewing a GEM Windows quote it is important to note that the sizes shown on the quote are for the aluminium frame size.

What do U’Values and SHGC Values mean?

SHGC measures how well a product blocks heat caused by sunlight. The SHGC is the fraction of incident solar radiation admitted through a window, both directly transmitted, and absorbed and subsequently released inward. SHGC is expressed as a number between 0 and 1. The lower a window’s SHGC, the less solar heat it transmits

U-Value measures how well a product prevents the heat from escaping. It is a measure of the rate of non solar heat loss or gain through material or assembly. It is also known as thermal transmittance or overall heat transfer co-efficient.