RAAC in commercial buildings: what do you need to know?

Reinforced aerated autoclaved concrete (RAAC) is in the headlines following high-profile building failures and public scrutiny on the risks remaining to public buildings around the country. But is RAAC a material of concern for commercial buildings? If owners or occupiers of commercial buildings suspect that their buildings are constructed using RAAC, what should they do?

Many commercial building owners are aware of risks relating to RAAC and have developed guidance notes on its identification and management. But now, in light of widespread coverage of RAAC and its risks, many more people want to understand their exposure to it.

TFT Partner Jay Ridings has written on this issue for the RICS’ Built Environment Journal, and we’ve also compiled this set of frequently asked questions about RAAC. If you want to know about its origins, its use and management today, read on.

Do you want to speak with our team urgently about RAAC and what it might mean for your commercial property? Get in touch with Jay Ridings direct, by clicking here.

What is Reinforced Aerated Autoclaved Concrete (RAAC)?

In brief:

Aerated autoclaved concrete (AAC) is much lighter and softer than regular concrete, with lower thermal conductivity. AAC was originally developed in Sweden to form lightweight thermal blocks and, using the same method, wide reinforced planks (Reinforced Autoclaved Aerated Concrete (RAAC) planks) were created. These planks are commonly found as roof decks, flooring and internal partitions. Occasionally they are also used as external walls.

What are the weaknesses of RAAC?

The greatest concern with RAAC planks is their potential for sudden shear failure. If a building structure is going to fail, we want this to happen by degrees so that there are warning signs to act on instead of immediate catastrophic failure. The reason for the shear failure is due to issues with the steel reinforcement, typically at the end of the planks.

Other concerns leading to deterioration of planks potentially impact their structural stability. Planks are prone to deflection and sagging, particularly if:

• Planks are incorrectly detailed
• Working loads have been underestimated
• Elements are undersized
• Reinforcement is inadequate

If there is sagging there is the potential for cracking and for the steel reinforcement to become exposed to moisture which could lead to corrosion. If roof planks begin to sag, water can gather on the roof above them (known as ponding). This may increase the load on the sagging planks, leading to further moisture ingress, exposure of the steel reinforcement, corrosion, and cracking.

Is RAAC found in commercial buildings?

In our experience, it is rare to see RAAC planks within commercial buildings. RAAC is most prominent in the public sector, notably schools and hospitals, but there are reports of its use in court buildings, prisons, and police stations.

However, these planks were available commercially and may be in buildings other than the above. In addition, buildings do change in their use and ownership over time, so there will be instances where buildings constructed within the public sector are now privately owned.

How do I know if my building contains RAAC?

There is no central register of buildings with RAAC planks, so identification depends on local knowledge and independent inspections. Here are some simple principles for identifying RAAC planks:

• Panels 600mm wide
• A distinctive V-shaped groove at regular spacing
• White or light grey colour
• On records or drawings, planks may be referred to by proprietary names such as Siporex, Durox, Celcon, Hebel and Ytong
• Panels are very soft and if you press a screwdriver or nail into the surface, you will be able to make an indentation. Please note: care should be taken when investigating in this way as applied surface finishes may contain asbestos.
• Inside, planks will appear bubbly like an Aero chocolate bar, with no visible stones (aggregate) in the panels.

If you suspect RAAC in your building, then an appropriately experienced Chartered Structural Engineer or Chartered Building Surveyor should be appointed for identification and inspection work.

Their investigations will include but are not limited to:

• Assessing cracking
• Measuring deflections
• Reviewing water penetration and corrosion
• Using cover meters to assess regular spacing of reinforcement
• Checking that reinforcement extends to the end of planks and is properly supported
• Taking and sending samples for laboratory testing

How can I manage RAAC?

If RAAC is discovered, you must undertake a risk assessment considering the use of the building, the areas affected and any deterioration of the structure. The position of reinforcement can be scanned using a cover meter and samples can be tested for carbonation, which is a sign that cracking could follow.

Structural engineers often recommend RAAC planks to be removed or strengthened wherever they are found, regardless of condition. This is because of the risk of sudden catastrophic failure and the fact that these planks are likely to have exceeded their design life. Subject to a full assessment of the risks, it may be possible to take a different approach.

Can you help me investigate RAAC in commercial buildings?

Yes, our team of Chartered Surveyors is on hand to investigate and manage improvements works for commercial buildings.

It is very likely there will be further discoveries and media attention on RAAC. News of failing buildings due to this outdated material highlights the urgent need for guidance and action to identify and implement remedial solutions.

Get in touch here to speak with our team about RAAC and what it might mean for your commercial property. Get in touch with Jay Ridings direct, by clicking here.

Cladding Safety Scheme: funds for building remediation works

The new Cladding Safety Scheme is open, and TFT is here to help building owners and occupiers access it. Although the application process can be complex, we offer four steps of support to help you secure the right funds and deliver safer buildings.

What is the Cladding Safety Scheme for?

The Cladding Safety Scheme is the second fund established by the UK Government to remedy unsafe cladding in residential buildings. This scheme is for buildings over 11 metres high. However, in London the scheme is only for medium-rise (11-18 metre) buildings.

The funds are only for remedying unsafe cladding on external walls. A condition of the funding is for you to carry out these remedial works swiftly, and to keep leaseholders informed along the way. 

Who can access these funds?

The person responsible for the external repair of the building is responsible for applications. This might include the freeholder, a Local Authority, a Right to Manage company or a Property Managing Agent.

In most cases, developers or owners which have signed up to the Developer’s Pledge should pay for building remediations through the Developer’s Pledge policy.

Whichever party is accessing the funds, they will need specialist support helps to compile the right information for success.

How can I apply for Cladding Safety Scheme funds?

The application process can be complex, requiring accurate building information and details of the proposed works to proceed, including: 

• A compliant fire risk assessment of the external walls (FRAEW) by a competent professional which identifies the cladding systems which require remediation
• A work package with full contractor schedule and costs 
• Statutory consents for the works
• Demonstrated value for money in the works package (by getting multiple quotes or running a tender process)

Missing information can lead to rejected applications, meaning more time taken to access the funds and remedy unsafe buildings. 

Four steps to secure the funds and complete the works

TFT has an experienced team ready to manage the assessment of buildings and support you through the process from end to end. We know the information required to support your application for building safety work funds. 

Our four-step process gives your application the best chance of success, and includes project managing building safety works to improve your buildings swiftly and with transparency. At the end of the process, building owners will have clear documentation to record the quality and detail of the works.

The result is peace of mind for building owners and occupiers.

Find out how this process can help you understand your building risks, and secure the funds to put them right. Get in touch with Robin Holme, here.

Sustainable procurement vs. supply chain risks

We are all too aware of the great risks facing construction projects today, but our industry is less aware of the more sustainable procurement solutions which could address them.

The nature of global supply chains can mean fluctuations in costs, project delays and inconsistent scrutiny on material provenance. The latter point has risen quickly up the agenda, considering high level ESG commitments which require developers and building owners to understand their carbon emissions and wider impacts beyond their site or asset.

Collaborative and measured approaches to material procurement can mitigate those risks.

In a recent article for Construction News, TFT Partner and Head of ESG Mat Lown wrote about new and better approaches to sustainable procurement which manage the carbon and financial risks faced by the construction industry.

More resourceful, sustainable approaches include considered design and material re-use. All require a realistic ‘whole life’ view of building products, such as:

Collaborate across projects and programmes

Procuring materials and reusing materials across a range of construction or demolition projects is a clear route to efficient and sustainable development. It hinges on a holistic approach to project and programme management.

A great example is Grosvenor’s Holbein Gardens, a redevelopment and one-storey extension of a 1980s office building off Sloane Square in London. It is one of the first projects in the UK to reuse steel salvaged directly from a demolition site, reducing embodied carbon and contributing to the growth of the second-hand materials market in our industry.

Addressing the environmental, social and governance agenda means that our teams are working more closely with contractors and material providers than ever before. We are seeing more interest in long-term contracts encompassing maintenance, upgrade and reuse of products during their lifespan.

Find out more about programme management.

Invest in your future supply chain

Leading developers and owners are taking a financial stake in key materials and suppliers to allow closer control over future supply chain issues. It means they can oversee production as well as the installation of materials.

Legal & General’s investment in modular-homes production is one example. The company now operates a dedicated 550,000-square-foot factory near Leeds, which can produce up to 3,500 properties per year. It demonstrates how businesses in our sector can take inspiration from other industries – such as aviation and automotive manufacturing – to supply much-needed homes in more efficient and sustainable ways.

Making these investments work is another challenge for collaboration. Getting the right specialist input to set up and monitor the success of production is critical.

Lay the groundwork for material re-use and smarter specifications

More prescriptive and accurate material specification means a higher quality product with less waste throughout an asset’s life. It’s easier said than done, but the work begins with effective collection and maintenance of building data. If building owners own a useful asset register that encompasses all the materials across their portfolio – with details of their state and potential for reuse – they can make more informed decisions about procurement and maintenance for sustainable use.

‘Materials passports’ offer a means of cataloguing the properties of a product or material, and Building Information Modelling (BIM) is the obvious channel for holding that information. Initially, such a model supports accurate specification and installation, then it informs future building maintenance work and subsequently the re-use opportunities for building materials or products in future schemes.

However, as with many technologies, such models can only succeed if a project team sets it up correctly from the outset and an occupier or owner team maintains it over time.

Are you looking for new opportunities to get more value from your buildings and development projects?

The approaches we describe here each require varying levels of commitment. But for those willing to adopt them, commercial benefits will follow.

Materials are fast becoming an ‘alternative’ commodity in the development process. They add to the commercial real estate equation of building value vs investment.

Are you looking for new opportunities to get more value from your buildings and development projects? Our teams can help you understand the scope for material re-use and plan for more sustainable built asset management. Together, we can help to lessen supply chain pressures and offer alternative solutions to meet demand for materials, helping to build resilience against future crises.

Want to find out more?

Contact Mat Lown, our Head of ESG and Sustainability services, here.

Contact David Medcraft, our Head of Development Management services, here.

What does 2022 have in store for retail property?

Retail property trends are a hot topic, as the sector continues to be dynamic in responding to new customer needs, and new players shake up the market. TFT is here to support our retail occupier, building owner and investor clients when their spaces need to change, or to ensure that new developments are set up for the future. Recently we’ve been involved with retail property instructions ranging from refurbishments and reconfigurations of shopping centres, retail parks and high street locations, as well as major new developments.

In summer 2021, we celebrated the opening of Edinburgh’s St James Quarter to the public. The project, which is Scotland’s largest and most significant mixed-use development project in a generation, is a landmark among the city’s retail and leisure offering which TFT monitored on behalf of the joint venture investors: Nuveen Real Estate and APG Asset Management.

After a mixed year for the sector, Retail Destination magazine spoke to Neil Wotherspoon, TFT Partner and head of our Edinburgh office, about the key retail property trends he’s watching in the months ahead. Here are some of his insights:

Supply chain disruption and changing expectations

The global supply chain has been heavily impacted by Covid, so delays and uncertainty around construction programmes remained even once sites were fully operational. one approach to mitigate that risk is by contractors buying materials in bulk to insulate from inflation further down the line.

As well as increasing material and labour costs, owners of retail property must consider the expectations and attitudes of their occupiers, which track customers’ changing priorities. As the shape of retail continues to shift, managing a portfolio requires some vision and investment, particularly for older centres which can be rejuvenated for a more modern clientele. Where those solutions can be found, they represent a more sustainable solution than demolition and development from scratch in many cases.

With no new retail developments coming through the pipeline, the focus will be on enhancing existing retail, particularly retail parks, to make it more experience-led and better adapted to a full day-out experience, coupled with convenience features.

I believe there is still cause for optimism although the reality is that landlords and developers will have to work harder than before. By creating mixed-use destinations including retail and leisure, operators and landlords can continue to perform well.

Neil Wotherspoon, Partner and head of TFT’s Edinburgh office

Check out Retail Destination’s article looking ahead to 2022, here.

Daylight and sunlight: new guidance, new questions

Many professionals and lay people (who aren’t daylight and sunlight surveyors) may assume that if a room has windows, it will be sufficiently lit by daylight. But our industry’s daylight and sunlight guidance and regulations contain much more nuance when it comes to determining good daylight provision, and there is plenty of debate behind the scenes. 

Now, an incoming third edition of the Building Research Establishment (BRE) Guidelines ‘Site Planning for Daylight and Sunlight’, is set to adopt new methods of daylight measurement. These will be taken from the British annex of the recently revised and updated European Standard ‘Daylight for Building’ BS EN 17037:2018 (BS 2018).  

Our standards for determining good natural light levels are set to change yet again. 

What do new daylight and sunlight changes mean for developers, occupiers, and surveyors? 

In advance of the BRE 2011 guidelines changing, we have already begun undertaking the new assessments for our clients and local authorities. BS 2018 provides updated assessment methods for quantifying the provision of daylight and sunlight to new rooms, and already supersedes the older ‘Lighting for Buildings – Code of Practice’ BS 8206:2:2008 (BS 2008). However, until formally adopted in the new BRE document, the older assessment methods in BS 2008 have not yet been fully phased out, so still inform the assessment methods used in current daylight assessments. 

We put all the daylight standards to the test to see how they stack up. A recent daylight and sunlight assessment project provided the opportunity to explore the new tests required by the BS 2018, and to compare them with the current BRE requirements for daylighting provision to new rooms, which are aligned to the older BS 2008. 

Our project brief was to analyse and quantify the potential daylight levels to rooms serving new residential apartments, in an existing building which was being reconfigured. We undertook daylight assessments firstly using the current standard ‘No Skyline’ (NSL) and ‘Average Daylight Factor’ (ADF) tests, which are based on the BRE 2011, and BS 2008. We then repeated the assessment with the newer tests specified in the BS 2018; the ‘Daylight Factor’ (DF) and ‘Illumination Level’ (LUX) methods. We then compared the different results for one example room in the existing building. 

What is different about the new daylight and sunlight assessments? 

The updated BS 2018 (and the UK National Annex within it), seek to improve upon previous assessment methods by allowing for more flexibility in acknowledging the difficulties designers face in designing for natural light in constrained urban sites, “… the recommendations for daylight provision in a space … may not be achievable for some buildings, particularly dwellings. The UK committee believes this could be the case for dwellings with basement rooms or those with significant external obstructions (for example, dwellings situated in a dense urban area or with tall trees outside), or for existing buildings being refurbished or converted into dwellings …”  The BS 2018 assessment methods seek to make tests, and the data which informs them, more robust and climate / site specific. The original ADF and NSL tests are relatively basic geometric tests, and do not consider the latitude or orientation of the site, only the nearest external obstructions to the windows, and relatively little in terms of internal reflectance values or finishes. 

Another important difference between the BS 2008 tests, and those of the BS 2018, is the treatment of the working plane or ‘reference’ plane. In the older tests the entirety of the room area if projected 0.85m up off the floor could be considered the working plane and assessed. The BS 2018 now requires that a 0.5m band around the perimeter of the room be excluded from the working plane and omitted from the tests. The remaining reference plane which is tested should result in less extreme individual highs and lows in daylight factors or lux levels across the room, which previously affected ADF results, especially for L-shaped rooms. However, whilst 0.5m exclusion band is recommended by the BS 2018, it remains to be seen if the updated BRE document will introduce more flexibility for this. 

When assessing new rooms to reconfigured existing buildings, L-shaped or narrow rooms are often inevitable and cannot always be completely designed out. Although the perimeter exclusion band to the rooms is intended to even out extreme contrasts in individual daylight results across the room and to the edges of the working plane, it is ironic that the “working plane” for most room occupants is where they put their furniture, which is often against the walls of the rooms, especially in narrow and small rooms. The perimeter exclusion band might result in excluding those parts of a room from assessment, which are most in use by the room occupants due to where they place their desks. The central areas of such rooms, often being used as circulation, would be the main reference plane tested. This means an exclusion band of 0.5m would seem unrealistic for long and narrow rooms, and not commensurate with how such rooms are often used. Consequently, in our study, we chose 0.3m as a more appropriate perimeter exclusion band. 

What did we find out? 

In a nutshell: the new BS 2018 methods benefit greatly by taking site specifics into account, allowing for a more detailed measure of a room’s daylight potential. However, even between the two new methods (DF and Lux) different outcomes occur which will raise more questions in future about how either assessment should be deployed. The test results have been summarised in Table 1 below.

Table 1, illustrates the visual similarities between the tests, based on where the light is shown to pool into the rooms on the working plane. However, there are notable differences between the testing criteria in each test type, so important variations in the results are also observed.   

Under the BS 2008 and BRE 2011 requirements, the LKD would not meet the ADF target value of 2% and would still fall short of an alternative target of 1.5%. It would conversely exceed the NSL target with 95% of the working plane achieving an unobstructed sky view. This is because these tests and their results only consider the most basic geometric obstructions outside the windows, and for the ADF, some generic reflectance assumptions for the room interior. No climate or geolocation specific data informs the tests or results. 

For both the DF and Lux tests required by the new BS 2018, the results are informed by location specific climate data, although more so for the Lux test which also considers orientation. In this case the DF results for the room fall slightly short of the recommended target values, whereas for the Lux test the results achieved meet the BS 2018 recommended targets. This shows the BS 2018 testing methods are more site specific and technically robust, but still produce differences between them, in how or if they meet the BS 2018 target criteria to achieve good daylight. 

The results of the comparative tests show that the two new tests from the BS 2018 are more comprehensive, and are more informative, when compared to the older BS 2008 tests. This could provide better outcomes for daylight consultants and clients as a result. Both new tests apply different parameters, so the choice of tests will allow for greater flexibility, so the daylight consultant can determine the most appropriate method to assess the space in question. In due course the new BRE Guidelines may provide additional guidance on which test is required (or if both are required), and this detail may be included in updated planning policy. The new BS 2018 also features updates to the calculations for Sunlight, Glare, and requirements for assessing Views, so it will be interesting to see how those are also incorporated into the new BRE Guidelines in the months ahead. The sunlight assessment will replace the APSH test for assessments of potential sunlight provision. However, this article has specifically focused on daylight. 

We hope this has provided some clarity and insight to an important change for daylight and sunlight standards. There remain more nuances and discussions to be had on the standards, so please do get in touch in advance of the release of the new BRE guidelines, to help you prepare for these changes. 

For more information, contact Richard Nosworthy.

Green Dilapidations on EG’s Property Podcast

With COP26 underway in Glasgow, Estates Gazette spoke with TFT Technical Partner Jon Rowling about our Green Dilapidations process, explaining how a new approach can create a more sustainable commercial leasing cycle.

Joining us on the EG Property Podcast are Siobhan Cross, real estate dispute resolution partner at Pinsent Masons, and Allan Clark, head of sustainability and facilities compliance at Pinsent Masons.

Together, the panel explains why Green Dilapidations is receiving more interest from occupiers, agents and lawyers. The discussion also highlights next steps to introduce measures for a less wasteful leasing process, and how those tactics work from a legal perspective, an occupier perspective and balance sustainable actions while also navigating commercial business issues.

Tune in to the podcast to find out more about Green Dilapidations, and get in touch with Jon Rowling to see how you can get started with a more sustainable approach to commercial property: https://estatesgazette.podbean.com/e/how-to-make-the-dilapidations-process-greener/

Green Dilapidations: more sustainable commercial property leases

Commercial building owners and occupiers are increasingly looking to fulfil their net zero carbon ambitions with measures beyond more sustainable development and energy performance practices. In particular, the current property leasing cycle and non-sustainable dilapidations processes are generating quantities of waste and carbon, which can be mitigated with a more sustainable approach: Green Dilapidations.

TFT’s Green Dilapidations services are designed to help clients reduce the additional material, resources and cost associated with repeatedly fitting out and stripping out commercial property spaces over their lifetime. Taking a long-term view of tenancy, occupier and market requirements, we help our clients benefit from a more efficient, sustainable dilapidations process for both landlord and tenant.

Our support is rooted in facilitating better collaboration between stakeholders. That means the landlord and tenant of course, but also agents and the wider supply chain. Our sustainable building knowledge, commercial understanding and dilapidations expertise helps to formalise a better system as a whole.

We see a greater appetite from our landlord and tenant clients to adopt Green Dilapidations services. A notable occupier client is one of the leading property litigation practices, who we are helping to exit their existing offices in this way. Our recent seminar on green dilapidations in June was well attended by a cross-section of the industry, showing the breadth of interest for specialist advice on the subject.

It’s not just for offices either, and can be used for retail, industrial and other commercial property sectors.

We’re here to help you do dilapidations in a better way. Get in touch with Jon Rowling to discuss how our dilapidations and sustainability expertise can help reduce the carbon impacts of your property lifecycle.

Download our brief service outline here.

Vacant possession: a new definition and advice for tenants

There has been a new Court of Appeal decision about vacant possession (“VP”) which changes what dilapidations professionals thought that VP meant after an earlier decision last year. That decision might have refined what we thought it might have meant since 2016, which probably changed what we had thought it meant prior to that. 

What’s changed, and what should you do about it?

Summarising the new decision on vacant possession:

The Court of Appeal (applying the facts of the case in front of it) has this week said that VP relates to the lack of the “trilogy of people, chattels, and interests”.

That wipes out what we thought VP meant after the case that was appealed was handed down last year.  That case had led us to believe that VP could fail to be achieved if too many of the landlord’s fixtures had been removed.  Now, it seems, a tenant can remove as many bits of the premises as it likes, VP can still be achieved, and the landlord’s remedy is in damages (only).

In 2016, obiter comments in a high court judgement (which mean those words in the judgement do not form part of a precedent) suggested that, if a tenant had left too many tenant’s fixtures in place (in circumstances where tenant’s fixtures did not form part of the premises – as defined) then VP would not have been achieved in that case.

What should a tenant do to achieve vacant possession?

• When exercising a VP conditional break, be cautious.  Get legal and surveying advice.
• Prepare early. Remove all people, chattels and interests and think about also removing your tenant’s fixtures if they do not form part of the demised premises.  If you are not sure if an item is a chattel or a tenant’s fixture; remove it.  It you are not sure if an item is a tenant’s fixture or a landlord’s fixture; remove it.
• Make it clear to your landlord that you are leaving, hand over keys, alarm codes etc.
• Don’t venture back into the premises after the break date.
• Make sure you also have complied with all other break conditions (such as getting notices right, making sure all payments have been made – even if not demanded by the landlord).

If there is no VP condition, but there is different wording, then you might be required to do other things.  If you are required ‘not to be in occupation’ then the process is less clear. It is probably less onerous than VP but nobody has been to court yet to find out.  Don’t be the one to go to court to find out! To be cautious, assume it means VP.

If the condition is to comply materially then that is very very difficult to do.  Assume you have to do everything perfectly and you have a chance.  But beware late reinstatement notices from your landlord changing the goal posts after a date when you can’t do anything about it.

If the condition is to comply absolutely then you probably have no chance, but if it is worth trying then try. 

Balance of power

The Court of Appeal decision has changed the balance of power more towards tenants if there is a VP condition to comply with.  But, the power still really lies with the landlords because courts have been very strict in making sure tenants comply with their obligations correctly. 

As this week’s judgement points out, that does not mean to say that the break clause should be interpreted unfairly in favour of landlords; rather, once the clause has been interpreted judges will expect strict compliance by tenants.

The cases referred to:

• Capitol Park Leeds plc (1), Capitol Park Barnsley Limited (2) v Global Radio Services Limited [2021] EWCA Civ 995
• Capitol Park Leeds plc (1) v Global Radio Services Limited [2020] EWHC 2750 (Ch)
• Riverside Park Limited v NHS Property Services Limited [2016] EWHC 1313 (Ch)

Virtual building surveys: 6 things you need to know

High quality visualisations produced by virtual building surveys are a powerful tool for investors, occupiers and other project stakeholders. We use them to save time when reviewing multiple buildings’ worth of information, or to communicate complex issues to non-technical specialists.

Here, we highlight the potential and limitations of the technology.

Read more

Dilapidations and demised premises: Where’s the rest of it?

Ben Sercombe makes the case for all parties to better document the contents of Demised Premises in their leases, to help reduce the expense, time and frustration which can result from dilapidations negotiations.

Read more