About standard E6.4

What is standard E 6.4?

• Standard E 6.4 is a requirement for natural daylight to be provided via all popholes in free-range sheds, in the event that birds need to be housed during the natural daylight hours and cannot access the range. For example, due to a compulsory housing order, bad weather*, or veterinary advice.
• The standard applies to all free-range sheds, whether new or existing.
• The use of natural daylight through popholes isn’t a new standard. We paused the standard in July 2025 to allow time to listen to feedback and address concerns around its implementation.
• In response, we proposed a series of case studies to demonstrate how producers could meet the standard in practice, using a range of different locations, shed types and potential solutions. However, we were unable to find any producers to volunteer to take part in these case studies.
• Now, with another high-risk avian influenza season on the way - and the potential for birds needing to be housed again without access to natural daylight - we believe it’s vital the standard is implemented to ensure hen welfare.
• The standard will come into effect for all free-range flocks placed from 1 December 2026.

*where relevant and permitted by national legislation.

What do free-range members have to do to meet this standard?

• Natural daylight needs to be provided via popholes whenever birds need to be housed during the day and are unable to access natural daylight outside.
• For example, due to a compulsory housing order, bad weather*, or veterinary advice*.
• One way of achieving this is to install a transparent or translucent material, such as toughened glass or acrylic, into the pophole door to create a window.
• The modifications need to be permanent. This is because the requirement applies whenever the popholes are closed, including situations such as maintenance work on the range or administering medication.
• Situations where birds need to be housed can also arise at short notice, so a permanent solution ensures natural daylight can be provided whenever required.

*where relevant and permitted by national legislation.

There have been several updates to the natural daylight standards, and I'm confused. Can you explain what applies and when?

• We appreciate that there have been several updates to the natural daylight standards over the last two years, and that it can be difficult to keep track of what applies to your farm.
• In July 2025, the RSPCA published the final version of the RSPCA’s laying hen standards, which included several standards relating to natural daylight. However, following concerns, we decided to pause standard E6.4 (the requirement for free-range houses to provide natural daylight through popholes during housing orders) so we could listen to feedback and address concerns around its implementation.
• This standard is now being resumed. Notification letters were sent to members on Wednesday 26 August, and it will come into effect from 1 December 2026.
• The implementation dates for the remaining natural daylight standards have not changed.
• To recap, the implementation dates for each of the natural daylight standards (E6.2, E6.3, E6.4) are as follows:

For free-range sheds

• New builds or structural refurbishments
  • Must meet standard E6.3 (d) as part of the construction or refurbishment from 1st October 2025, and natural daylight must be provided entirely by windows.
  • New builds and structural refurbishments must add windows to achieve 3% natural daylight in addition to the light provided through popholes.
  • For all flocks placed after 1st of December 2026, pophole light must be maintained any time the birds are housed during daylight hours (E6.4). This means that, in practice, these houses will move towards providing more than 5% natural daylight overall when pophole light is also taken into account.
• Internal refurbishments
  • Must meet standard E6.3 (b) as part of that refurbishment using any valid light inlets, including popholes.
  • This standard came into effect from 11 July 2025, when the final version of the standards was published.
  • Planned internal refurbishments (e.g converting from flat deck to multi-tier) must include improvements to the popholes or light inlets or windows so that the house can achieve the 3% natural daylight requirement.
  • These improvements should be carried out as part of the internal refurbishment.
  • For all flocks placed after 1 December 2026, pophole light must be maintained any time the birds are housed during daylight hours (E6.4).
• Existing sheds
  • Existing sheds undergoing no planned changes must meet standard E 6.3 (c) by 1 January 2035, giving almost 10 years to meet the standards in full.
  • Natural daylight may be provided using any valid light inlets, including popholes.
  • There is no retrospective requirement for existing multi-tier or flat-deck free-range houses to immediately provide 3% natural daylight outside their normal refurbishment cycles.
  • For flocks placed from 1st December 2026, natural daylight (standard E6.4) must be provided via all popholes within the building when birds need to be housed during the natural daylight period.
• For barn sheds
  • New builds from 1 October 2025 must meet standard E 6.2 (c) from construction, using windows only.
  • Existing sheds must meet standard E 6.2 (b) by 1 May 2032, using windows only.
  • E6.4 does not apply to barn producers as they do not provide popholes onto the range.
• We are on hand to support our members in achieving these over the coming years. Members who need advice or have any questions about meeting the standard can contact RSPCA Assured’s farming and technical engagement team, who will be happy to help.

*The RSPCA and RSPCA Assured’s driving priority is to support all members in achieving the standard by 2035. If 3% minimum natural daylight cannot be reasonably and realistically achieved through refurbishment by 2035, a five-year derogation will be available for members to apply for - if they can commit to refurbishing to 3% natural daylight by 2040. Any member granted a derogation will be subject to certain conditions.

What's the point of E6.4? These are free-range birds that can go outside and get natural daylight.

• Free-range hens access natural daylight when they are outside, but on occasions when they need to be housed during daylight hours, they don’t benefit from natural daylight, which is important for their welfare.
• It is also important to recognise that not all hens will choose to range. Some hens have lower motivation to go outside, meaning they may spend much of their time indoors and have less opportunity to experience natural daylight.
• Natural daylight can support hens to express important natural behaviours, including foraging, dustbathing and exploring their environment. Providing natural daylight indoors helps create an environment that encourages hens to remain active and engage positively with their surroundings.
• In other higher-welfare poultry systems in the UK and Europe, such as meat chickens, providing windows and natural daylight is already standard practice because of the recognised welfare benefits.
• Standard E6.4 is intended to ensure that hens are not kept in an artificially lit indoor environment in the event they are temporarily unable to access the range.
• The aim is to maintain the natural daylight indoors that the birds would normally experience when ranging outdoors, through the popholes when they have access to the range.

What are the welfare benefits of giving natural daylight to hens?

• Natural daylight is important for hen welfare, but it is not commonly provided to laying hens housed in barns in the UK. For free-range hens, natural daylight is currently primarily available through open popholes.
• Hens have a preference for natural daylight, and it provides them with access to the full visual light spectrum, helping to keep them stimulated and supporting their welfare.
• Natural daylight also encourages a range of activities, such as foraging, preening and dustbathing.
• For free-range hens, natural daylight can also encourage ranging by reducing the differences between the indoor and outdoor environments.
• Further information: The RSPCA has published research on the benefits of natural daylight for laying hens, which provides further information on the welfare benefits and the scientific evidence behind the approach.
  • Understanding natural daylight for kids
  • Natural daylight

Compliance with the standard

What does the implementation date (1 December 2026) mean for my flock?

• This means if you are due to place your flock on or after 1 Dec 2026, standard E6.4 will apply to you.
• If you place your flocks on or before 30 November 2026, E6.4 will not apply to that flock. The standard will need to be met when the next flock is placed.

What if my site has three sheds with 16,000-birds that are due to be repopulated over a couple of days, e.g 29 November, 30 November and 1 December?

• Each 16,000-bird shed is considered a separate flock for the purposes of this requirement. Therefore:
  • The flocks placed on 29 November and 30 November 2026 would not need to comply with E6.4.
  • The flock placed on 1 December 2026 would need to comply with E6.4.

What if one flock is being placed over two days, over the cut-off date - i.e. one on 30 November and one on 1 December?

• In this situation, the producer will not have completed placing the flock before 30 November, and therefore, the flock will need to comply with E6.4.
• From 1 December 2026, all existing free-range members must meet the standard to retain their RSPCA Assured certification.

Outside of a housing order, am I able to open the popholes a little bit to let the light in but not a big enough gap for the hens to get out?

• No, this would not be compliant with E6.4.
• Opening the popholes only slightly would not provide the same level of natural daylight that would normally enter through the popholes when they are fully open. The amount of light entering the house would only be a fraction of what the birds would normally experience.
• A permanent solution must therefore be made to the popholes to ensure sufficient natural daylight can enter whenever the birds need to be housed.

What could modifications to popholes look like?

• Ideally, we would like to see windows fitted into the pophole doors that can be instantly deployed when the birds need to be housed.
• Other possible solutions could include:
  • Fitting sheets of transparent or translucent material over the internal pophole opening, keeping the hens inside while allowing the external pophole to remain open; or
  • Other suitable permanent modifications that allow natural daylight to enter while preventing birds from accessing the range.
• Producers should consider the design of their individual sheds and choose a solution that provides sufficient natural daylight while allowing the birds to remain safely housed.
• If you are unsure what to do, our farming and technical engagement team is here to help and advise. You can reach out to them by emailing help@rspcaassured.org.uk.

I don't normally need to house my birds, so do I need to make changes to my popholes?

• Yes, you will still be required to make changes to your popholes.
• The need to house birds during daylight hours can be unpredictable. For example, birds may need to be housed because of a compulsory housing order, bad weather, veterinary advice, maintenance work or another unforeseen circumstance.
• Standard E6.4 therefore requires producers to have a suitable solution in place before it is needed, rather than making modifications only when birds unexpectedly have to be housed.
• The requirement is about protecting hen welfare and ensuring that natural daylight can be provided whenever birds need to remain indoors during daylight hours.

I am a barn producer. How does standard E6.4 affect me?

• E6.4 does not apply to barn producers as they do not provide popholes onto the range.

What will assessors be looking for at assessment for E6.4?

• What the assessor looks for will depend on whether the birds are currently housed, are due to be housed, or have previously been housed. Here are some scenarios to help you understand what they will look for in different situations:
  • When birds are housed:
    • Assessors will look for modifications that are being used and that allow the full amount of natural daylight normally provided through the popholes to enter the shed. This could include:
      • Popholes that have been permanently converted into windows
      • Removable solutions that fit over or into the pophole opening
  • When birds are due to be housed:
    • Assessors will look for evidence that the modifications are already in place and ready to be used. For example:
      • Windows have been added to the popholes
      • Removable modifications have been cut to the correct size and are ready to install
      • The popholes have been modified so that the solutions can be installed when required.
  • When birds have previously been housed:
    • Assessors may look for evidence that the modifications have been used when required.
    • Taking photographs is a good way of demonstrating to an assessor how you have complied with E6.4, particularly where the modifications are removed when birds are no longer required to be housed.

My popholes are equivalent to 3.7% of the floor area. Do I need to modify all of my popholes, or just enough to provide 3%?

• Yes, all popholes must be modified.
• Standard E6.4 applies to all popholes, not just a proportion of them. The purpose of E6.4 is to maintain the natural daylight that hens would normally receive through the popholes when they are open.
• Therefore, the standard applies to all popholes.

My popholes exceed the minimum requirements in the RSPCA laying hen standards. Do I need to modify the additional popholes too?

• Yes, you will need to modify all of your popholes.
• Standard E6.4 applies to all popholes, even where a shed has more popholes than the minimum required under the RSPCA laying hen standards.
• The requirement is about maintaining the level of natural daylight that hens would normally receive through the popholes when they have access to the range.

My shed is naturally ventilated and already has lots of natural daylight. Do I still need to comply with E6.4?

• Yes, you still need to comply with the standard.
• Standard E6.4 applies to all free-range sheds, regardless of their ventilation system or the amount of natural daylight already provided through other light inlets.
• The requirement is specifically about ensuring that the natural daylight normally entering through the popholes is maintained when birds are housed.

My shed already has windows. Do I still need to comply?

• Yes, you still need to comply with the standard.
• Standard E6.4 applies regardless of whether the shed already has windows or other sources of natural daylight.
• The purpose of the standard is to maintain the natural daylight normally entering through the popholes when birds are housed and cannot access the range.

I'm concerned about light pollution from the modified popholes. What can I do?

• Standard E6.4 requires natural daylight to be provided during the daylight period, for a minimum of eight hours of continuous daylight per day - except where the natural daylight period is shorter than eight hours.
• This does not mean that the popholes need to provide light throughout the night. When it is dark, the popholes can be closed, so the modified popholes should not create an ongoing light pollution issue during hours of darkness.

I'm concerned that people could see into the shed through the modified popholes. What can I do?

• Frosted or translucent materials can be used to prevent people from seeing directly into the shed while still allowing natural daylight to enter.
• It is also worth remembering that people could, if they wanted to, already see into the shed through open popholes when the birds have normal access to the range.

Some of my popholes only receive indirect light at certain times of the day. What's the point of modifying those popholes?

• The purpose of E6.4 is to maintain the natural daylight levels that the hens would normally experience through the popholes.
• If a particular pophole normally provides only indirect daylight at certain times of the day, the modification should maintain that same source of natural daylight when the birds are housed.
• The requirement is not about ensuring that every pophole provides the same amount of direct sunlight throughout the day. It is about ensuring that the natural daylight normally entering through the popholes is not lost when the birds are confined indoors.

We have just had new LED lighting installed, and we can change the colours and wavelengths. What's the point of E6.4 when we can provide artificial lighting that mimics natural daylight?

• Natural daylight is extremely complex and contains a broad range of wavelengths that change throughout the day.
• Although modern LED systems that do not flicker can reproduce particular wavelengths and create sophisticated lighting environments that have benefits for bird welfare, they cannot replicate the full profile and complexity of natural daylight.
• They should only be used to complement natural daylight.
• For this reason, natural daylight remains the preferred source of light where it can be provided.

What if I have a veranda? Do I need to do this?

• Verandas are not a requirement for free-range members. Producers can choose to provide a veranda, and the RSPCA encourages producers to install compliant verandas where possible.
• However, if a producer installs a new veranda after 11 July 2025, it must meet the RSPCA's veranda standards.
• Whether any changes are needed to the popholes depends on whether the veranda is compliant and whether the birds have access to it whenever they are housed.
• If you have a compliant veranda:
  • If the veranda meets the veranda standards and is available to the birds whenever they are housed, the internal popholes will not be closed, and E6.4 will therefore be met.
  • This is because compliant verandas are designed to provide substantial natural light and ventilation. Under the standards, a veranda must:
    • Have a total floor area of at least 20% of the usable area of the main house; and
    • Provide natural air circulation and natural light to achieve an outdoor climate through openings representing 70% of the external side wall.
  • As compliant verandas are large and provide significant natural light, birds will continue to have access to natural daylight when housed.
  • If birds lose access to the veranda at any time while they are housed, the internal popholes must be modified to ensure that the natural daylight coming through the popholes is maintained.
• If you have a non-compliant veranda:
  • If the veranda does not meet the veranda standards but is available to the birds whenever they are housed, the external popholes must be adapted to maintain the natural daylight entering through the external popholes.
  • If birds lose access to the veranda at any time while they are housed, the internal popholes must be modified to ensure that natural daylight entering through the popholes is maintained.
• In summary: Verandas are optional for free-range members, but any new veranda installed after 11 July 2025 must meet the veranda standards. If birds have continuous access to a compliant veranda while housed, E6.4 will be met without modifications to the internal popholes. Where access to the veranda is lost, modifications will be needed to maintain the natural daylight available to the birds.

Concerns about hen behaviour and natural daylight

I'm concerned about my birds seeing outside through the pophole and becoming frustrated because they can't go out.

• Housing birds can cause frustration, whether they are housed for a short period or for an extended period.
• We recommend providing additional high-value, novel enrichment when birds are housed. This gives hens alternative positive activities to engage with while they cannot access the range.
• For example, scatter feeding at particular times of day can encourage foraging behaviour. If a new form of enrichment is introduced, it is important to maintain it consistently once it has been established.
• Another option is to use a translucent material for the pophole modification. This allows natural daylight to enter while reducing the hens' ability to clearly see the range outside.

I'm concerned that natural daylight from the popholes could cause smothering or feather pecking.

For further information and support:

• Behaviour advice