Retro Panes are designed to fit most windows, especially single-glazed wooden sash and case windows. 

However, they can be adapted for a variety of other window types. To ensure a perfect fit, consider the following points. If you're uncertain, feel free to email us or order a single Retro Pane to test our secondary glazing.

Frame depth

Retro Panes have a total depth of 15mm. Your window frame needs to have a depth of at least 13mm to accommodate the panel.

Window furniture (sash locks & sash eyes)

If sash locks or other window furniture are installed and obstruct the 15mm frame from slotting in, these items can be replaced or relocated. For detailed advice and instructions, please refer to our installation section.

Frame angle

The angle between the glass surface (primary glazing) and the frame should ideally be no more than 110 degrees. 

Most frames have a 90-degree angle. If your frame angle exceeds 110 degrees, the foam may not hold the pane securely. In such cases, we can use additional tape to secure the pane to the primary glazing, provided the primary glazing is sufficiently strong (+3mm thick).

Beading

If your window has beading (approximately 5mm) that seals the primary glazing into the frame, we will still need at least 13mm of frame space after the beading to properly slot the panel into your window.

Frame materials

Retro Panes can be fitted to any frame material.

Retro Panes are highly effective at reducing and often completely eliminating condensation.

Condensation during particularly cold days

If you notice condensation on cold days, it may indicate that your windows are not properly sealed. Typically, this means that moisture is entering the cavity through the wood or small gaps between the primary glazing and the wooden window frame. This often suggests that your window frames require refurbishment, such as repainting or sealing.

Quick fix

Releasing the panes and wiping away the condensation is a simple and straightforward solution.

Heave preexisting condensation issues

If your windows frequently suffer from significant condensation, please contact us for a case-by-case assessment. Alternatively, you can order a single pane to test our glazing system firsthand.

Retro Panes are classed as secondary glazing. Secondary glazing and secondary windows are generally approved for listed properties, as long as they don't "result in any permanent change to the character of the building, are easily reversed and have no impact on the fabric of the original window."

Historic England has provided guidance on this, stating that "Secondary glazing, when carefully designed and installed, allows the original windows to be retained unaltered... As a result, there is no loss of historic fabric, and in most cases, the installation is easily reversible."

Retro Panes are even less intrusive than traditional secondary glazing since they don't require fixings like screws or nails, and are easily detachable.

You can find more guidance in this document from Historic England: Secondary Glazing in Historic Buildings.

Further information can also be found, published by the Centre for
Sustainable Energy and the Bath Preservation Trust:

Warmer Bath: A guide to improving the energy efficiency
of traditional homes in the city of Bath

The amount of heat that can pass through a typical single glazed window, or its thermal transmittance is approximately 5.2 - 5.4W/m²K.

The chart below shows that the thermal performance of Retro Panes is comparable to that of double glazing, achieving a reduction in thermal transmittance of up to 50%.

Professional Survey and Installation:

Currently, our professional survey and installation services are available exclusively in the following areas:

• Bath
• Bristol
• London
• Edinburgh
• Glasgow

Nationwide DIY Orders:

All our products are available for nationwide delivery. For customers outside our service areas, you can order our secondary glazing products using our DIY option.

All Retro Panes are made to order.

Measurement Responsibility

Professional Measurement Service: If the measurement survey is conducted by us through our professional measurement service, we take full responsibility for providing Retro Panes in the accurate size.

Customer Measurements: If the measurements are provided by the customer, we cannot guarantee an accurate fit. Please follow our measurement instructions carefully and contact us if you have any questions. Panes will always be manufactured to the customer's specifications. If there are issues with a DIY order, please contact us to find an agreeable solution for both parties.

Damaged Goods

Transit Damage: Goods that are damaged during transit will be replaced free of charge.

Cancellation and Returns

Goods made to your specifications and correctly supplied, which are not faulty, cannot be returned. If in doubt, please get in contact or start with a single pane order.

We carefully select our materials to ensure high quality.

The overall Retro Panes come with a 5-year warranty covering all other potential issues, such as material failure or disintegration.

As a material, Acrylic used to suffer from yellowing because of specific chemicals within it. However, production processes over the last decade have dramatically reduced this. Therefore, our Acrylic supplier provides a 10-year guarantee against changes such as cracking or yellowing, and so we pass this guarantee on to our customers