Development Director, Jonny Stevenson shares his views on second stair cores in residential developments.
The safety of residents in high-rise buildings has been a pressing issue in recent years, with tragic incidents such as the Grenfell Tower fire in 2017 serving as a stark reminder of the critical importance of fire safety measures. As a response to this issue, the UK government has proposed changes to Building Regulations Approved Document B (Fire Safety), which includes the introduction of a threshold whereby residential buildings above 30 metres in height should be designed with two staircases. In this blog post, we will discuss the potential impacts of this change on new and existing residential developments, including the cost implications and the potential impact on affordable housing.
The introduction of second stair cores in residential development is a significant change that could have a massive impact on developers, particularly in terms of cost. To retrofit consented schemes that are not yet implemented, significant design adjustments may be necessary, potentially resulting in a loss of NIA/units, time, and cost. Additionally, it may be necessary to renegotiate affordable housing viability if new planning applications are required, creating additional financial uncertainty in addition to the added build cost expenses and design complications.
In addition to the impact on development costs and affordable housing, the introduction of second stair cores is likely to affect all high-rise schemes not yet on site, including those with consent. Because of this, developers may need to adjust their plans to accommodate the change. For instance, in one case, a developer had to submit a revised land offer that accounted for the additional cost of both the secondary stair core and the cost of extra piling to support the extra concrete, which led to a one-third reduction in land value.
Despite the potential cost implications, the introduction of second stair cores in high rise residential development is increasingly being seen as essential for fire safety. It is important to advise clients on how appropriate changes can be incorporated in a manner that meets (or exceeds) emerging guidance, whilst being secured within an efficient timeframe to ensure the delivery of new homes isn’t significantly stalled. Newsteer has already advised one client on a non-material planning amendment to a consented scheme to include two additional stair cores, an effective measure taken without loss of units but with a reduction in NIA/unit sizes that impacts GDV and land value slightly. Despite the slight reduction in value, it allows a consent to be implemented quicker and most cost effectively than pursuing a new application.
Furthermore, there might be instances where buildings proposed or consented to are only slightly over 30m, giving developers the opportunity to reduce their building’s height under s96a to avoid the need for a secondary stair core, which our client is doing for a scheme in south east London.
Although the introduction of second stair cores may be a significant investment in terms of build cost and loss of net internal area, it is a crucial measure for protecting the safety of residents in high-rise buildings. It is essential for developers to factor this into their plans, particularly in the design stage, to avoid significant costs associated with retroactive changes, including the loss of NIA/units and potential renegotiation of affordable housing viability. While there might be opportunities in s96a regulations to avoid such measures in marginal cases, putting aside addressing the proposed additional fire safety measures as an afterthought is simply not an option.
The Government is proposing a ‘very short’ transition period before implementing the changes, with a lack of detailed guidance creating uncertainty. The National Fire Chiefs Councils (‘NFCC’) Single Staircases Policy, also published in December 2022 recommends that the threshold should be lowered to 18 metres/7 storeys; creating a clear conflict with the Government’s 30 metre consultation threshold. Some of our registered provider clients are already saying that they would struggle to obtain board approval for schemes over than 18m that did not have a second staircase.
The government’s consultation acknowledges that the costs of a second stair core will impact the viability of high-rise buildings. Newsteer are already starting to consider emerging viability arguments to manage the process effectively for our clients. Together, we need to ensure that the safety of residents in high-rise residential buildings remains a top priority in the delivery of new homes, including affordable housing.
To discuss how Newsteer can assist with the viability, planning or marketability of your sites and schemes that may be affected by this issue, get in contact: