Understanding Window Types and Materials
Windows are essential features of any property, contributing to its aesthetic appeal, insulation, and overall functionality. With so many different types of windows available, it’s important to understand the materials, styles, and common defects associated with each type.
This helps you make informed decisions when replacing or installing windows. Whether you’re working with traditional properties or more modern builds, the choice of window can make a significant difference to your home’s energy efficiency and overall look.
Window Types: Materials and Styles
There are various types of windows, each offering different benefits and features. In general, windows can be categorized by both their material and operational style.
Materials
Timber: Classic and traditional, timber windows are often used in period properties.
UPVC: Popular from the 1960s onwards, UPVC is low-maintenance and energy-efficient.
Aluminium: Modern, durable, and typically used in newer builds or for sleek, contemporary designs.
Metal: Often found in historical properties, particularly in mansion blocks in North London.
Styles
Sash Windows: These are the most common type of window found in period properties, especially in Victorian homes throughout North London. Timber sash windows are a defining feature of properties in areas like Finsbury Park, Crouch End, and Stroud Green, often required in conservation areas to preserve the building's historical character. These windows are typically designed to slide up and down but can also be side-hung. Sash windows in North London can be crafted from timber to retain the traditional aesthetic of the property, and they can be fitted with double or secondary glazing for improved insulation.
Casement Windows: Casement windows are often associated with UPVC and timber frames. This window style is hinged on the side or top and opens outward, offering excellent ventilation and clear views. While traditionally found in more modern buildings, timber casement windows can also be used in period homes, though UPVC is far more common due to its lower maintenance requirements and cost-effectiveness. Casement windows are a popular choice for homes built in the mid-20th century and onward, especially in areas like Tottenham and similar post-1950s developments. These windows are commonly found in homes from this era and can also be used in properties undergoing renovation for a clean, modern look.
Tilt-and-Turn Windows: Typically associated with aluminium frames, tilt-and-turn windows are popular in more modern properties, especially in urban developments and tower blocks. This window style allows for flexible opening, either tilting inwards for ventilation or swinging fully open for easy cleaning. Their contemporary design and ability to handle large panes of glass make them a top choice for high-rise buildings or homes where light and views are a priority. While they offer excellent thermal efficiency and noise reduction, they’re generally not found in traditional period properties.
In North London, you can find tilt-and-turn windows in newer developments like Woodberry Down or other contemporary apartment complexes, where they offer both aesthetic appeal and practical benefits. These windows are a great fit for modern urban living spaces.
Modern and Conservation Area Considerations
When it comes to more modern buildings, such as tower blocks or new homes, you’ll find windows like double-glazed or tilt-and-turn windows, which are particularly common in high-rise buildings. However, in areas like Finsbury Park, Crouch End, or Stroud Green, which are known for their period properties, living in a conservation area will often mean that you’ll be restricted to using timber sash windows to preserve the area’s historic character. The type of window you can use will depend on the specific regulations of the conservation area and the type of property you’re working with.
1. Timber Windows
Timber windows are a classic choice, especially for properties in historic areas. Timber sash windows are often required in conservation areas to maintain the authentic look of the property. While aesthetically pleasing and suitable for older properties, timber windows do require ongoing maintenance. Over time, timber is prone to rot, warping, and swelling, especially if not properly maintained. Regular painting and sealing are essential to protect against the elements.
Lifespan: Timber windows, when properly maintained, can last 30-50 years or more. Without care, however, their lifespan can be significantly shortened.
2. UPVC Windows
UPVC windows, which gained popularity in the 1960s and 1970s, are known for their durability, low maintenance, and cost-effectiveness. These windows are weather-resistant and provide excellent insulation, making them a good choice for modern homes. They are often used as a replacement for timber windows because of their long lifespan and low upkeep.
However, while UPVC windows are energy-efficient, they may not always be suitable for period properties, especially in conservation areas. They can appear out of place on older buildings and might not comply with local planning regulations if they detract from the character of the property.
Lifespan: Typically, UPVC windows last around 20-35 years before the seals and frames may begin to show signs of wear.
3. Aluminium Windows
Aluminium windows are a popular choice for more modern or industrial-style buildings. They provide a sleek, contemporary look with slim frames, allowing larger panes of glass for better natural light and views. Aluminium is a highly durable material, resistant to corrosion and requiring minimal maintenance. However, it can be a conductor of heat, which makes it essential to use thermally broken aluminium to prevent heat loss and condensation.
In North London, aluminium windows are often used in more contemporary properties or developments, but they are less common in period homes or in conservation areas where original materials like timber are required.
Lifespan: Aluminium windows typically last 40-50 years, depending on the quality and maintenance.
4. Metal Windows
Metal windows, often made from steel or cast iron, were more commonly used in mid-20th-century buildings, particularly in mansion blocks across North London. These windows are robust and secure but prone to sweating, which can cause condensation and affect the nearby walls, leading to dampness and poor seals. In North London’s climate, these windows are more common in historical buildings and should be regularly maintained to prevent rust and degradation.
While they are durable, metal windows are often less energy-efficient than newer materials like UPVC or aluminium. If you’re renovating a property with metal windows, it’s important to inspect the frames regularly for signs of rust and condensation, particularly in areas with high humidity.
Lifespan: Metal windows can last 40+ years, but require regular maintenance to prevent rust and corrosion.
5. Window Performance: Insulation and Glazing Options
When it comes to the performance of windows, one of the most important factors to consider is thermal efficiency. Double-glazed windows are standard in modern homes, providing better insulation than single-glazed windows. Triple glazing is even more effective for energy efficiency, offering superior heat retention and soundproofing. In conservation areas, secondary glazing is often used as a solution to improve insulation without altering the external appearance of the windows.
Lifespan of Glazing: Double-glazed windows typically last 20-30 years before the seals may deteriorate, while triple glazing can last longer, especially if maintained properly.
6. Exposing Lintels and Proper Support
When replacing or repairing windows, pay attention to the lintels, the structural supports above the windows. Lintels in older properties can be weakened over time and must be properly supported before any window work begins. It’s vital to hire a competent, regulated contractor to ensure the lintels are properly supported to avoid causing further damage to the property.
7. Working with Competent Contractors and Warranties
When installing or replacing windows, it’s essential to work with a FENSA-registered contractor. FENSA ensures that windows are installed according to the correct building regulations. Additionally, insurance-backed warranties should be provided for new windows. Most reputable manufacturers offer warranties ranging from 10 to 20 years on both the windows and the glazing.
Warranties: Always ensure that your windows come with a warranty to protect your investment. This warranty typically covers defects in materials and installation, with some glazing manufacturers providing up to a 20-year warranty on the glass itself. If the contractor does not offer a warranty or guarantees the work, it’s worth considering another contractor.
Conclusion
Choosing the right windows for your property is essential, not only for aesthetic appeal but also for functionality. When replacing or installing windows, it's important to consider the regulations of your local council, especially if you live in a conservation area. Always take into account the existing windows in the property, including their size, type, and material, as well as how they affect the overall thermal performance of the property.
At Tollington Surveyors, we have a deep understanding of windows and the common issues that can arise with different materials and styles. During our HomeBuyer and Building Surveys, we look for typical defects, check the operation of windows, and assess their condition to provide practical advice. We make recommendations based on what’s best for the property and its current state—whether that’s upgrading windows, re-cording sash windows, or addressing thermal inefficiency.
We also know that when it comes to window replacements, purchasing in bulk can sometimes be a cost-effective option, especially in larger renovations.
Always ensure you're working with a competent, FENSA-approved contractor and ask for warranties on both the windows and the installation. Taking these steps will give you peace of mind and help ensure your windows are in good condition for years to come. If you have any questions or would like further advice on your property’s windows or other concerns, feel free to get in touch with us.
Tollington Surveyors is a small, locally-focused surveying company based in Stroud Green, and dedicated to serving the Haringey area. Learn more >
