Working examples for natural daylight
To help you achieve the natural daylight standard, we’ve provided a range of working examples below. These different scenarios and solutions are designed to help you understand how to implement natural daylight across different systems and situations. If you need further advice and support, please contact our Farming and Technical Engagement team.
Scenario 1: internal refurbishment, multi-tier
Farmer Adam has a 32,000-capacity twin multi-tier shed with 2.8% natural daylight and it remains that way until he refurbishes the shed by replacing the multi-tier system.
This refurbishment triggers the standard as follows:
At refurbishment, he must find a way to increase natural daylight to meet the 3% minimum standard by adding another opportunity for a light opening or finding another place to put a light inlet/non-ranging pophole, e.g. beyond the bird area (most sheds have extra length)
Scenario 2: internal refurbishment, flat deck
Farmer Brian has a 16,000-capacity flat deck shed with 1.7% natural daylight and, like Adam, it remains that way until his plan to replace his nest boxes or his flat deck system.
This refurbishment triggers the standard as follows:
At refurbishment, he must find a way to increase natural daylight to meet the 3% minimum standard. By putting additional pophole openings along the length of his shed during the refurbishment, he is able to meet the minimum 3% standard
Brian decides to add some non-ranging popholes with clear acrylic (Perspex) to achieve the additional natural daylight.
Scenario 3: major structural refurbishment
Farmer Christine has a flat deck shed and wants to become a multi-tier producer.
This refurbishment triggers the standard as follows:
To achieve this she needs to make major structural changes to the whole shed to accommodate the multi-tier system. At refurbishment, she must now fit 3% windows to her shed, and also ensure the quantity of popholes is sufficient to meet 2m per 600 birds for the increased bird number.
Scenario 4: major structural refurbishment
Farmer Lesley has a 16,000 capacity multi-tier shed and wants to expand the shed to accommodate 32,000 hens. To achieve this they need to rebuild the outer structure of the shed.
This refurbishment triggers the standard as follows:
As the building work involves changing the external structure of the shed at refurbishment, they must now fit 3% windows to their extended shed.
Scenario 5: new build, multi-tier
Farmer David currently has beef cattle and wants to expand into laying hens. As such, he is building a brand new 16,000-capacity multi-tier shed.
This new build triggers the standard as follows:
As it is a brand new multi-tier shed, he must fit 3% windows as part of the design.
Scenario 6: new build, flat deck
Farmer Angela currently wants to start farming laying hens on a small scale and builds a new 9,000 capacity flat deck shed.
This flat deck new build triggers the standard as follows:
As it is a brand new shed, she must fit 3% windows as part of the design.
RSPCA definitions used in the scenarios below
An internal refurbishment is defined as:
a full system or near full system change, such as the replacement of an existing multi-tier system with a new multi-tier system or any change that results in a system being removed and then returned, e.g. the replacement of nest boxes.
- any change to the system that results in an increase in bird numbers (e.g. the replacement of an existing flat deck system with a multi-tier system).
- the extension of an existing building to incorporate an additional flock.
- An internal refurbishment does not include the replacement of accessories such as drinkers, feeders, perches, or ventilation and lighting systems.
A structural refurbishment is defined as any refurbishment that involves a change to the structure of the building, such as the removal of wall(s) or a change in wall or roof height. It includes any situation where planning permission is required to repair any damage to a building, e.g. when caused by fire, flood or storm damage.
Scenario 7
Question: A producer has natural daylight in their shed corresponding to over 3.0% of the total floor area. They are not planning any changes to their shed, internally or externally, other than normal/routine maintenance, which may include replacing the feeders or drinkers.
Answer: The producer does not need to make any changes as they are already meeting the 2025 natural daylight standard requirements. This is assuming that the producer has made provisions for natural daylight to be provided via popholes within the building if birds need to be housed during the natural daylight period for all new flocks placed after 1 October 2025.
Scenario 8
Question: A producer has natural daylight in their shed corresponding to below 3% of the total floor area. They are not planning any changes to their shed, internally or externally, other than normal/routine maintenance, which may include replacing the feeders or drinkers.
Answer: By 1 October 2025, natural daylight must be provided via popholes within the building when birds need to be housed during the natural daylight period (in the case of a housing order) for all new flocks placed after this date.
By 1 January 2035, natural daylight corresponding to at least 3% of the total floor area has to be achieved; this can be met through the popholes, e.g. by extending the popholes.
If 3% minimum natural daylight cannot be reasonably and realistically achieved through refurbishment by 2035, a five-year exception will be available for members to apply for, if they can commit to refurbishing to 3% natural daylight by 2040. Any member granted an exception will be subject to certain conditions.
Scenario 9
Question: A producer is replacing their nest boxes, i.e. an internal change in March 2032.
Answer: This internal change will trigger natural daylight by 3% of the floor area being met through the popholes, e.g. by extending their popholes at the time that the nest boxes are changed. It may be that producers would only have to make small changes to meet the 3% as the existing popholes would count towards the 3% requirement.
Scenario 10
Question: A producer is replacing their flat deck with multi-tier i.e. an internal change in March 2032, and there are no structural changes required to the building.
Answer: This internal change will trigger natural daylight by 3% of the total floor area being met through the popholes, e.g. extending their popholes at the time that the flat deck is changed.
Scenario 11
Question: A producer is replacing their flat deck system with a multi-tier system in March 2037, with no structural changes to the building. The house already has natural daylight openings corresponding to 3% of the total floor area of the house.
Answer: No changes needed to comply with the natural daylight requirement, as the standard, 3% by popholes, has already been achieved.
Scenario 12
Question: A producer is making some structural changes to the building by extending their existing shed to increase their flock size after 1 October 2025.
Answer: This change is deemed a ‘major’ structural change and will trigger natural daylight by 3% of the floor area being met by windows, at the time that the extension is being built. This is in addition to the natural daylight provided through the pop holes, i.e. popholes cannot be used to count towards achieving the 3% requirement.
If the producer has already applied for, or been granted, planning permission and can evidence this occurred prior to 1 October 2025, they can apply for an exception to enable them to continue their planning applications under the 2017 requirements. The overarching requirement to meet the 3% natural daylight by 2035 will remain (e.g. 3% can be achieved through popholes).
Scenario 13
Question: If a site has 3 sheds and the producer is making a structural change to only one shed, will the first 2 sheds have to comply with the natural daylight requirements via the installation of windows?
Answer: All sheds must provide natural daylight via all popholes within the building when birds need to be housed during the natural daylight period for all new flocks placed from 1st October 2025.
The shed undergoing the structural refurbishment will require the installation of windows (if this is built from 1st October 2025) to meet the 3%, as popholes would not count towards the 3% due to the structural changes being made to the building. If the two original sheds are not undergoing a structural refurbishment, these sheds would be required to have natural daylight openings that correspond to at least 3% of the total floor area of the house through popholes by 2035.
Scenario 14
Question: If a producer is currently building a new shed and it will be completed before 1 October 2025, what natural light requirements are needed?
Answer: In this example, the shed will be completed prior to 1 October 2025, therefore, the shed will not have to install windows but will have to ensure 3% natural daylight is provided through popholes by 2035.
All sheds must provide natural daylight via all popholes within the building when birds need to be housed during the natural daylight period for all new flocks placed from 1 October 2025.
By 1 January 2035, natural daylight corresponding to at least 3% of the total floor area has to be achieved; this can be met through the popholes, e.g. by extending the popholes.
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.
Scenario 15
Question: If a producer has existing planning permission or submitted plans awaiting approval, but the new shed will not be built until after 1 October 2025, what natural light requirements apply?
Answer: All sheds must provide natural daylight via popholes within the building when birds need to be housed during the natural daylight period for all new flocks placed from 1 October 2025. Producers who can evidence the below would be able to apply for an exception to enable them to continue their planning applications under the 2017 requirements, i.e. they would not need to add windows as part of their new build if that has not been factored into their plans.
- An existing written contract with an egg packer is already in place
- Planning permission has already been submitted to erect the building(s)
- Significant capital has been invested into the affected building(s) or its infrastructure
Any members with concerns should contact the RSPCA Farming and Technical Engagement Team at the earliest opportunity to ensure compliance with this standard. This way, we can consider the best way forward on a case-by-case basis.
It is important to note that if an exception is granted, producers will still have to provide the requirement to meet the 3% natural daylight requirements by 2035. Therefore, it is important that producers consider whether the designs can be adapted to extend popholes to meet the 3% requirement while they are delivering their new build.