Precise measurement of your old window opening is crucial when installing double glazed windows and double glazed doors. Because UPVC double glazed windows are custom-built, they cannot be returned if ordered incorrectly. This is why our trained technicians take exact measurements before manufacture in Sydney for all replacement windows and doors, and some new constructions. Our windows and doors are typically manufactured to a +/-2 mm accuracy to ensure the best fit.

We recommend having qualified technicians, such as window installers or glaziers, handle the installation and glazing of our energy efficient windows. Nevertheless, we do receive many requests from DIY enthusiasts for supply-only options. While we are happy to provide double glazed windows and doors on a supply-only basis, we have found that self-installation or work by independent tradespeople can sometimes compromise the quality. For example, an unfilled gap between the wall and the window can decrease the window's noise insulation and energy efficiency.

Please be aware that we are not responsible for incorrect installations if we did not perform them. We advise contacting the installer responsible. We do offer services to correct poor installations, even those from our competitors, but a fee is charged based on the complexity and number of items. Additionally, we offer consultation services for builders unfamiliar with UPVC double glazed windows.

To prevent DIY disasters, we have compiled installation tips based on our experience fixing problematic installations. These tips are meant as suggestions rather than a step-by-step guide. Each installation can have unique challenges, such as weather or architectural issues, that may require expert knowledge. Thus, while our information is accurate, it should not be solely relied upon.

Before starting, confirm the size, style, and position of your new double glazed window against your order. A perfectly installed window is ineffective if it is upside-down or meant for another room. UPVC windows are not designed to be loadbearing, so a lintel might be needed above the window. If unsure, consult a qualified fitter or surveyor. The new window should be about 10 mm smaller in height and width than the brick opening. Clear the area by removing curtains, blinds, and ornaments.

To remove the existing window:

1. Cover the area with durable dustsheets inside and out.

2. Remove all opening sashes using a screwdriver or nail bar.

3. Carefully crack the glass in fixed lights with a screwdriver/punch and light hammer, starting at the top corner.

4. Dispose of the cracked glass shards in a plastic bin.

5. Break the plaster seal around the window frame with a Stanley knife.

6. Cut through the vertical (mullion) and horizontal (transom) frame members with a crosscut saw and remove.

7. Carefully cut through the outer frame jambs, head, and sill to minimize damage to plaster, brickwork, and damp-proof membrane.

8. Use a nail bar to lever the framework away from the plaster line.

9. Clean away debris around the opening with a masonry chisel.

To fit the new window:

1. Position the cill profile onto the brickwork, ensuring the upstand is snug against the plaster line of the jambs.

2. Level the cill with plastic packers, leaving about 5mm clearance between it and the brickwork.

3. Secure the cill with 8 x 100 mm fixing bolts, 150 mm from each end and at 600 mm centers.

4. Apply silicone along the back edge of the cill upstand.

5. Secure the end caps into position with silicone or superglue.

6. Remove all glazing beads from the window frame and mark them for replacement.

7. Position the new window with the base snug against the cill upstand, ensuring a tight silicone seal.

8. Wedge the window into position with plastic packers and check for vertical alignment with a spirit level.

9. Secure the window to the cill with #8 x 40 posidrive screws and the window jambs to the brickwork with 8 x 100 mm fixing bolts, avoiding the head of the window to prevent damage.

10. Check for squareness within the outer frame.

Glazing notes:

1. Position 25 x 100 x 15 glazing bridges in the frame recess with a dab of silicone.

2. Place a 28 x 100 x 5 glazing packer on the bottom glazing bridges.

3. Position the glass sealed unit in the aperture, ensuring it is central.

4. Use hand pressure to position additional 2 mm glass packers for squareness.

5. Open and close the sashes to check for smooth operation and adjust packers as needed.

6. Clip back the glazing beads in the order of top, bottom, then sides.

7. Apply a silicone bead between the outside masonry and window frame, and an acrylic bead between the inside plaster and window.

8. Remove protective tape from the window frame and clean with warm soapy water.

After installation, check the window's operation. It should open and close smoothly and be airtight when closed. If the window appears crooked, it has not been installed correctly. Ensure the sash fits into the frame without gaps and operates smoothly.