What is uPVC Windows? A Complete Guide

What is uPVC Windows?

uPVC windows are windows made with frames of unplasticised polyvinyl chloride, a rigid plastic material that does not contain the plasticisers used to make standard PVC flexible.

What is the Main Difference Between PVC and uPVC Windows?

The main difference between PVC and uPVC windows is the use of plasticisers. PVC contains plasticisers, which make the material softer and more flexible. This makes PVC suitable for products such as electrical wires, toys, shower curtains, and clothing. uPVC does not contain plasticisers, so it is harder and more rigid, making it better suited for window frames, doors, and water pipes.

Why to Choose uPVC For Your Windows?

uPVC is a popular choice for windows because it is durable, low maintenance, energy-efficient, and resistant to moisture and corrosion. Unlike timber, it does not rot, warp, or require regular painting.

Its multi-chambered frame design can also help reduce heat transfer, especially when paired with double or triple glazing. uPVC windows are also easy to clean, offer good weather resistance, and are available in a wide range of styles and finishes.

So, when you invest in uPVC windows, you’re choosing a material that offers superior performance in terms of longevity, energy efficiency, and ease of maintenance. 

Are uPVC Windows Energy Efficient Enough?

Yes. Modern uPVC windows are energy efficient enough for most homes, especially when fitted with good double or triple glazing.

For an easy comparison, the lower the U-value, the better the window keeps heat inside. In Ireland, SEAI recommends choosing windows with a whole-window U-value of 1.4 W/m²K or lower.

How Long Can uPVC Windows Last?

UPVC windows, when well-maintained, can last anywhere between 20 to 30 years.

Is uPVC Weatherproof?

Yes. uPVC is highly weather-resistant and is well suited to windows and doors exposed to rain, wind, moisture, and changing temperatures.

Unlike timber, uPVC does not absorb water, so it does not rot, swell, or need regular sealing or painting. It also does not rust like metal. Modern uPVC frames are designed with sealed joints, drainage channels, and weather gaskets to help keep water and draughts out.