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Installing new UPVC windows can transform your home’s energy efficiency and appearance. This guide walks you through the professional installation process, helping you understand what’s involved whether you’re DIYing or hiring an installer.
Why Choose UPVC Windows?
UPVC windows have become Ireland’s most popular choice for good reason. They offer excellent thermal insulation, require minimal maintenance, and can last 20-25 years with proper care. Modern UPVC frames are available in various styles and colors to match any home aesthetic.
Preparing for Installation
Before starting your window replacement project, you’ll need to measure your existing openings accurately. Most suppliers offer made-to-measure services where windows are manufactured to your exact specifications and delivered ready to install. Standard sizes are also available for common openings, which can be more cost-effective.
What You’ll Need
For a successful installation, gather these essential tools:
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Spirit level (at least 600mm)
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Electric drill with masonry bits
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Screwdriver set
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Wooden wedges
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Silicone sealant
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Wall plugs and fixing screws
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Damp-proof course (DPC) material
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Mortar mix
Step-by-Step Installation Process
Remove the Old Window
Carefully remove your existing window frame, taking care not to damage the surrounding brickwork. Clean the opening thoroughly, removing old sealant, debris, and loose mortar.
Position the New Frame
Modern UPVC windows typically come with an outer frame that gets secured to your wall. Place the frame into the opening and use wooden wedges underneath the sill to position it correctly. The sill must be perfectly horizontal before proceeding.
Check and Adjust Levels
Use your spirit level to verify that all sides are vertically upright. Check diagonally from corner to corner to ensure the frame is perfectly square. Small adjustments now prevent major problems later. Add or adjust wedges as needed until everything is perfectly level.
Secure the Frame
Once you’re satisfied with the positioning, it’s time to fix the frame permanently. Drill through the frame at regular intervals into the brickwork behind. Most installations require:
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Two fixings on each vertical side (top and bottom)
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Additional fixings along the sill for wider windows
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Fixings every 600-800mm for larger installations
Add Damp Protection
Install a damp-proof course (DPC) strip along the bottom of the frame where it meets the brickwork. Mix a small amount of mortar to bed the DPC properly, creating a waterproof barrier that prevents moisture penetration.
Final Securing
Insert wall plugs into the drilled holes and drive screws through the frame. As you tighten each screw, continuously check with your spirit level to ensure the frame remains perfectly square and level. Over-tightening can distort the frame, so apply even pressure.
Seal and Finish
Apply silicone sealant around the exterior perimeter where the frame meets the brickwork. This weatherproofs the installation and prevents drafts. Inside, you may need to replaster or add architrave trim around the frame for a professional finish.
Common Installation Mistakes to Avoid
Don’t rush the leveling process—a frame that’s even slightly off will cause operational issues and premature wear. Always use the correct fixings for your wall type (brick, block, or stone). Insufficient fixings can lead to frame movement and seal failure.
Professional Installation vs DIY
While experienced DIYers can successfully install UPVC windows, professional installation offers several advantages. Installers provide warranties on both the product and workmanship, have specialized tools, and can handle unexpected complications like non-standard openings or structural issues.
Building Regulations and Standards
In Ireland, window replacement must comply with Building Regulations Part L (Conservation of Fuel and Energy). Professional installers are familiar with these requirements and can ensure your installation meets current standards for thermal performance and ventilation.
Ready to upgrade your windows? Expert Windows offers professional UPVC window installation throughout Ireland. Our experienced team handles everything from measurement to final fitting, ensuring perfect results backed by comprehensive warranties. Contact us today for a free consultation and quote.
