Frequently Asked Questions

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Gecko Panes

Gecko Panes are made-to-measure clear plastic panes which pop just inside the frame of your existing windows.

By trapping a layer of air, which is a strong insulator, they cut heat loss and emissions by half, which is nearly as good as conventional double glazing but at a fraction of the effort and cost.

Unlike any other system, Gecko Panes fit into almost any window in seconds, with no tools or DIY skills needed. As they don’t damage windows in any way and are fully removable, they’re particularly good for period properties.

A Gecko Pane simply traps a 12mm layer of air beside the single glazed pane. This acts as an insulating layer, cutting heat loss by up to 48%.

The thickness of a second sheet of glass makes almost no difference to the U-value, which is why Gecko Panes achieve nearly 50% heat loss reduction using just 2mm of thick clear plastic, making it more cost effective for everyone.

Gecko Panes also drastically reduce condensation because they raise the temperature of the pane such that the dew point is less often reached.

And to top it off, the combination of the Gecko Pane, captured air and your original window significantly reduce noise pollution.

Note: Gecko Panes do not improve leaky, ill-fitting frames. Draught proofing, if necessary, is best undertaken as an additional measure.

A single glazed pane typically has a U-value, which indicates its ability to transmit heat from a warm space to a cold space, of 5.8 w/m2˚C, and that a double glazed pane with a 12mm air filled cavity (a Gecko Pane) has a U-value of 2.9 w/m2˚C, which is half as much.

Research by the Building Research Establishment suggests that heat loss through a typical timber framed single glazed window should be reduced by nearly half (48%) because the U-value is reduced from 5.8 to 2.8.
Gecko Panes have increased effectiveness if they are attached to an already double glazed window, and though research is pending, U-value calculators suggest that the further heat loss reduction would be around 30%, from around 2.9 to around 2.1.

This substantial improvement demonstrates the significant impact that Gecko Panes can have on energy efficiency. Please have a look at the thermal performance modelling of Gecko Panels here.

Gecko Panes always reduce condensation in well-sealed, dry windows.

A little moist room air can be caught between a Gecko Pane and the window’s glass during installation, and this can cause misting on very cold days. This usually disappears as the day warms and doesn’t affect the thermal properties of Gecko Panes – they are still reducing heat loss as intended.

Popping out Gecko Panes to wipe away any moisture building up is really straightforward. If it has to be done regularly, this normally just indicates that windows need a new coat of paint.

Georgian windows (with many small panes separated by thin glazing bars) that suffer from dampness should be assessed before installing Gecko Panes.

The good news is that Gecko Panes work well with Georgian windows, and windows that rarely suffer from dampness or with an exterior framework that is in great condition are almost always fine.

However, if your Georgian windows do suffer from dampness, they may be poorly sealed. This can happen because greater care needs to be taken with the narrow timber glazing bars to ensure they remain well-sealed on the outside (exterior).

If not well-sealed, exterior moisture might get between the glass and Gecko Pane. This should be removed regularly. Doing so is easy straightforward but, if you have many multi-pane Georgian windows, it can be time-consuming.

For Georgian windows that suffer from dampness, check there are no cracks in the outside putty, that exterior paint is not flaking and that paint overlaps the glass panes by 1-2mm all round (this is key to effective sealing).

If in doubt, install a single Gecko Pane in dampest window. If no moisture occurs in cold seasons, install more Gecko Panes. If rapid moisture build-up does occur, either remove the build-up of moisture regularly or repaint the windows.

Repainting poorly sealed windows is highly advisable as it significantly prolongs their lifespan.

Although an innovative form of it, Gecko Panes meet the official definition of secondary glazing for RDSAP purposes. Domestic Energy Assessors should record them as such when calculating EPC uplifts.

Analysis by the Building Research Establishment suggests that installing Gecko Panes in single glazed properties could result in an EPC rating uplift of up to 3 points.

Gecko Panes can also be used to improve the performance of older double glazing, but the reduction in heat loss is less than in the case of single glazing.

Looking at their performance, the difference between conventional double glazing and Gecko Panes is that double glazing also uses ‘low-emissivity’ glass and inert gas in the cavity to cut heat loss further. This improves the U-value to about 1.8–2.0 W/m²°C from 2.9 W/m²°C, an improvement of only about 15–20%. In other words, 80% of the benefits are achieved simply by trapping a layer of air, which is what Gecko Panes do.

Single glazing is a terrible insulator, transmitting 5.8 watts of heat per square metre, per degree Celsius. That’s 5–10 times as much as a wall, which is why single glazed windows feel so cold, and why they can cause such a significant loss of heat.
As cold single glazed panes cool the air next to them, the air sinks, drawing warm air down from ceiling height which causes convection currents (draughts) and discomfort, losing heat.

When the glass temperature is below the ‘dew point’, the warm air convecting through the window condenses water onto the pane causing misting and dampness.

If your home has several single glazed windows, it will raise your heating costs, and the emissions associated with heating your home, significantly.


For a window to suit a Gecko Pane, its frame must meet the glass at 90 degrees and where they meet must be at least 12mm deep.

The window also needs to be rectangular. We can’t manufacture Gecko Panes for curved windows, windows with curved corners or windows with different angles (e.g. triangular windows).

To clean the Gecko Pane, ensure that you use a very soft cloth (micro fibre is best) to avoid scratching the acrylic.
A soap and water solution or general-purpose cleaning spray is best. Apply your cleaning solution sparingly to ensure that excess moisture can’t penetrate into the cavity where it may cause misting.

Avoid using glass cleaning products which contain ammonia, as these may damage the pane.

Gecko panes will also prevent the inside glass surface of your window pane from becoming dirty, so that’s one less thing to worry about!

Gecko Panes tend to pay for themselves around ten times faster than conventional double or secondary glazing. And as a general rule of thumb, this should normally take 2-6 years in fairly normal circumstances.

However, the rate at which they pay for themselves depends upon a range of factors, including your type of heating system (gas, electric, etc.) and its efficiency; how much you pay for gas or electricity; or the temperature to which, and how often, you heat the rooms in which Gecko Panes are installed.

The following infrared pictures show the impact of installing a Gecko Pane. In this picture, only the middle-left Gecko Pane is missing. Note the dark blue of the pane, indicating a significantly colder surface.

We know that Gecko Panes will deliver their promised heat loss reduction, but it’s nice to have tangible evidence of their performance, right? On very cold days, the difference made by a Gecko Pane is clear, especially if you have a single glazed pane next to it. Placing your hand near to the surface of each, you’ll notice that the one with the Gecko Pane feels several degrees warmer.

Another indication of performance is that Gecko Panes significantly reduce, or even eliminate, condensation on panes that are otherwise prone to it. In the picture below, the left-hand window has no Gecko Panes, but the right hand one does.

Finally, all other things being equal, fully outfitting a home with Gecko Panes should make a noticeable difference to your energy bills.


Gecko Panes are usually far more affordable than alternative upgrades, but financial support is still often available. Gecko Panes count as secondary glazing for grant or interest free loan support.

Home Energy Scotland provide interest free loans to those living within Scotland to help with the cost. Currently, customers require (1) an initial Energy Performance Certificate (EPC) that suggests secondary glazing is appropriate, (2) an updated EPC after the gecko panes have been installed and (3) your Gecko Panes must be professionally installed (i.e. financial support is not available if the Gecko Panes are self-installed). Check out the Home Energy Scotland website for more details, or pick up the phone and give us a call.

For financial support outside of Scotland, we suggest the Energy Saving Trust website as the first port of call for more information.

Gecko Panes cost £195 per square metre.

For example, an average four-pane sash window costs approx. £300-500 to ‘Gecko Glaze’. A six-pane bay window tends to cost approx. £500-700. In terms of a whole home, a three bedroom house should cost approx. £3000.


We provide convenient UK-wide delivery services, with shipping costs varying based on the pane’s size, which offers a wide range of options. If you decide to proceed with delivery:

Our standard shipping timeframe is 2-3 days.

For specific delivery date requests, please reach out to our customer service team.
We partner with various shipping providers, and while we can’t pre-determine the exact provider, rest assured that we aim for the most reliable service.

Alternatively, you can opt to collect your order from our workshop at no additional charge. Visit us at:

Gecko Glazing
Unit 4, Russell Road Industrial Estate
Sauchiebank – Edinburgh EH11 2NN

For international shipping inquiries, please feel free to send us a message. We’re here to assist you in exploring suitable options.


Regarding general orders, due to the custom nature of our products tailored to your windows, we regret that returns are not feasible. Should any quality issues or faults arise, we provide hassle-free replacements at no extra cost to you.

Your satisfaction is our priority.

We’re nice people, and we want customers to be able to try out Gecko Panes as affordably as possible, so we always suggest that new customers buy one pane in the first instance, so that they can appreciate the benefits without a large financial outlay.

Taking this one step further, if you install a Gecko Pane and you decide they’re not for you, just let us know. If the pane is less than 0.3 square metres (say 50cm x 60cm or similar), we’ll refund you the full cost of the pane (not including the shipping cost).

If the pane is larger than that, we’ll refund 50% of the cost of the pane (not including the shipping cost).

Please note that we don’t combine multiple discounts.