Ad description

A TV ad for JML Direct Navy Seal Draught Shield Tape, seen in February 2023, featured a draught excluding tape. A voice-over stated, “Keep out the cold and seal in the warmth with Navy Seal Draught Shield Tape from JML. The insulating tape that blocks gaps and cracks around your windows and doors in a flash. Just look at the temperature difference around this leaky door”. Two thermal images of the same door then appeared on screen; the first door labelled “BEFORE” radiated a blue and green light, and the second door labelled “Navy Seal Draught Shield Tape” radiated red light, including in the centre of the door. A scale ranging in colour from blue to green was positioned at the bottom of the screen. Blue was labelled “COLD” and red was labelled “HOT” on the scale.

The voice-over continued, “Simply cut and stick to create a strong and flexible seal that snaps back into place. Helping to protect your home from draughts and chills. Insulate your home and save money on your heating bills with a triple pack Navy Seal Draught Shield from JML.” Alongside that, two clips of foiled paper attached to the edge of the same door were shown; the foiled paper in the “BEFORE” clip appeared to waft, and the foiled paper in the clip labelled “Navy Seal Draught Shield Tape” was stationary. Text on-screen also stated “INSULATE YOUR HOME” and “SAVE MONEY”.


Two complainants challenged whether the ad misleadingly exaggerated the efficacy of Navy Seal Draught Shield Tape.


John Mills Ltd t/a JML defined heat loss as the movement of heat from one material to another. They explained that if heat escaped in an uncontrolled manner that any given heating system would have to work harder to replace it. They further detailed that controlled ventilation helped to reduce condensation and damp by allowing in fresh air when needed, but that draughts were uncontrolled. As a consequence, they said that draughts allowed too much heat to escape as well as letting in cold air and could cause up to 15% heat loss in a home. They therefore considered that draught-proofing was one of the cheapest and most effective ways to save energy and money in any type of building. They highlighted that, in order to draught-proof a home, individuals should block up unwanted gaps. By doing that, they considered that an individual would be able to use less energy to heat their home.

JML also stated the product had a returns rate of 0.12% and provided us with copies of five papers which they considered substantiated that the draught seal was fit for purpose and that the ad did not misleadingly exaggerate the efficacy of the product. They consisted of two independent studies, one in-house testing report and two papers that explained the difference between colour palettes in thermal imaging.

Clearcast said they were provided with independent test reports which they considered demonstrated the efficacy of the tape in preventing significant levels of heat loss. Specifically, they stated that one of the reports measured air flow as 0.52 metres per second (m/s) without the tape and as 0.003 m/s when the tape had been applied. They also referred to the thermal imagery and stated that the report showed that, when the tape was applied, the door was warmer. As a result, they concluded that the tape performed effectively and preventing draughts and heat loss.

Clearcast acknowledged that the thermal imagery colours in the ad were not the same as the colour shades in the report. They explained that this was because a different colour palette had been used in the ad but that they were satisfied that imagery was equivalent to that shared in the report.

Clearcast also accepted that draught-proofing was not a form of insulation. However, they reiterated their belief that it was one of the cheapest and most effective ways to save energy and money in a building because blocking unwanted gaps resulted in reduced air flow, which in turn, would enable an individual to reduce their central heating use. They considered that to have a similar effect to insulating floors and walls, and consequently, did not consider the terms “insulating” and “insulate” to be misleading.





The ASA understood that draught excluding tape enabled consumers to block up gaps around windows and doors so that air flow was restricted, preventing cold air from entering a property and warm air from leaving. We noted the thermal imagery which featured in the ad ‒ specifically, that the “AFTER” image radiated red light across the whole of the doorframe and the centre of the door. We considered that suggested the draught tape was able to prevent heat loss across the door itself, as well as the entire doorframe where the tape had been placed. We also noted that the draught excluding tape was described as an “insulating tape” and that it could “insulate your home and save money on your heating bills”.

Whilst we acknowledged that consumers would likely not consider draught excluders to be a form of insulation, such as cavity wall or loft insulation, we considered that they would interpret those claims, along with the before and after imagery, to mean that the product was able to reduce significant heat loss across surfaces and that using them would considerably increase the temperature of a home. We therefore expected that JML would be able to demonstrate that the product prevented significant heat loss, across the doorframe and in areas where the tape had not been directly placed, as well as an ability to increase the temperature of the home.

We assessed the evidence provided by the advertiser. We examined the first independent study, and noted that it assessed the adhesive nature of the tape and its waterproof resistance, which we did not consider was directly relevant in supporting the efficacy of the tape in retaining heat.

We then assessed the second independent study which evaluated the effectiveness of the tape in preventing draughts and heat loss. Firstly, to test the efficacy of the tape in preventing draughts, airflow was measured both before and after the application of the tape. We noted that after the application of the tape that air flow reduced from 0.52 m/s to 0.03 m/s and considered that demonstrated the tape could be used effectively to reduce airflow and draughts. However, we understood that this test did not measure heat loss or the temperature of the home, and as such considered it did not substantiate the tape’s ability to retain a significant amount of heat across surfaces.

We then examined the second test within the study which evaluated the tape’s effectiveness in preventing heat loss. A door with suitable gaps was heated on one side, while the other side was left at an ambient temperature, and a thermal imaging camera was used to assess where heat loss occurred. The tape was then applied, and the process was repeated. We noted that, at the time the test was conducted, the temperature of the room was 35 degrees Celsius. We considered that consumers’ homes were generally not, and extremely unlikely to ever be 35 degrees Celsius. We therefore considered that, by conducting the test in conditions which were significantly hotter than the average UK home, that any resulting “after” imagery would not reflect the likely effect of the product as it was intended to be used by UK consumers.

We then analysed the “before” and “after” thermal imagery resulting from the test. We noted that in the “after” image, the colour which denoted a cool temperature, had decreased around the gaps in the doorframe and the middle portion of the door, and that the colour demonstrating a hot temperature had increased across the upper portion of the door. However, we noted that a considerable portion of the gaps between the door, as well as the door itself, remained in colours which indicated a cool temperature and, therefore, that heat loss was still occurring. We considered that did not align with the “after” imagery shown in the ad, in which red light emanated from the whole of the doorframe, nor did it substantiate that the tape would considerably increase the temperature of a home.

We also noted that the thermal imagery in this study used the ‘Ironbow’ colour palette, which differed from the ‘Rainbow’ colour palette used in the ad. We noted from the two reports supplied by JML that different colour palettes could be applied to the same thermal image, and that whilst the same results would be reflected in the images, different colour ranges were used to display the information. However, we understood that the Rainbow palette utilised a wider variety of colours and was commonly used to differentiate between minimal heat differences. As such, we considered that the contrast between the before and after images in the ad may have appeared more dramatic than the reality of the temperature difference.

We then examined the in-house study. We noted that neither the methodology nor the temperature at which the tests took place were referenced within the study. Because of that, we were unable to sufficiently analyse the conditions under which the test took place.

Notwithstanding that, we noted that two sets of before and after imagery had been included in the study. The “after” image in the first set contained an increased proportion of warmer colours, which indicated a high temperature, and therefore suggested that a certain level of heat had been retained after application of the tape. However, we noted that there was no red light emanating from the doorframe. As such, we considered that it did not match the imagery used it the ad, nor did it sufficiently substantiate that the tape prevented heat loss across the whole doorframe as indicated by the ad. The second set of images was reflective of the way in which the tape is used in the United States, where we understood that the tape was used to keep homes cooler, rather than warmer. As such, the “before” image radiated a red colour and the “after” image radiated a blue and green colour. We noted that the second set of before and after images matched those used in the ad but that the “before” and “after” images had been swapped to reflect the U.K. consumer’s use of the tape. We considered that it was misleading to use that imagery within the ad to portray the tape’s ability to prevent heat loss because the temperature demonstrated by the image had not been achieved by application of the tape. We further considered that, because the image was taken at a high temperature, and subsequently used to depict the ability of the tape to retain heat, that it misleadingly exaggerated the level of heat that could feasibly be retained by using the product.

Because JML had not been able to sufficiently demonstrate that the draught excluder tape significantly reduced heat loss across doors or doorframes in conditions that were reflective of a UK consumer, we concluded that the ad misleadingly exaggerated the efficacy of the product.

The ad breached BCAP Code rules 3.1 (Misleading Advertising), 3.9 (Substantiation), and 3.12 (Exaggeration).


The ad must not be broadcast again in its current form. We told John Mills Ltd t/a JML to ensure that they did not misleadingly exaggerate the efficacy of the Navy Seal Draught in the absence of adequate substantiation.


3.9     3.1     3.12    

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