Types Of Window

Domestic windows usually have timber, PVC or metal frames. This troubleshooting guide discusses common problems encountered with each of these materials and suggests remedial treatments.

Timber was always the traditional choice for window frames and remains a popular contemporary choice, especially for double glazing. Hardwood is the more durable option though treated softwood is also used. Regular maintenance, and weatherproofing every five years with paint or wood stain, should avoid timber defects and guarantee a long serviceable life.

However, if allowed to fall into disrepair, the chief problem with timber windows is usually wet rot. This usually appears when the wood is allowed to remain permanently damp through, for example, leaking putty or a deteriorating paint layer.

The simple solution is a resin repair where the rot is scraped away, built up with a resin layer, sanded and repainted. Larger rotted sections can be treated by cutting away the bad section and then splicing in new wood, though the glass and frame must come out to achieve this. Where the stability and strength of the frame has been compromised, the remaining, and most expensive, option is replacement with a new timber frame.

Alterations to Building Regulations, requiring double glazing to be fitted in both new homes and extensions, have made PVC the preferred choice for window frames in the last two decades. They have been marketed as an affordable, energy-saving product requiring no maintenance beyond installation. In reality, double glazing often develops condensation problems over time when moisture penetrates the seals and seeps into the void between the glass plates. New glass, with fresh seals, can be fitted into the frames to remedy this.

Actually, first-generation PVC windows quickly developed a faded and discoloured look, when exposed to sunlight, because of the use of lead in their manufacture. Current, state-of-the-art, PVC windows are a considerable improvement, displaying greater condensation resistance and impressive energy-saving performance.

Metal frames first became fashionable with the introduction of the curved ‘suntrap’, or ‘Crittall’ windows of the 1920’s ‘art deco’ period. However, with the exception of a few architectural specimens, most of these single-glaze windows have long since been replaced because of inferior thermal insulation and consequent issues with condensation. Metal frames can twist and buckle if subjected to structural distress and the resultant distortion brings about malfunctioning of handles and hinges, along with scuffed frame surfaces and ill-fitting windows. Rust can corrode and damage frames if water comes into contact with unprotected metal surfaces. Acid or abrasive material will remove minor rust damage but more serious corrosion will require the damaged section to be replaced with new metal.

Aluminium windows combine lightness and strength, allowing scope for some futuristic designs. Aluminium has a good lifespan but high thermal conductance has been a drawback. This has been resolved, on later products, by placing a ‘thermal break’ between the internal and external frame sections.

For expert help and advicecheck out the You Choose website. We can help with a question regarding box sash windows.