New Draft London Guidance On Affordable Housing/Viability

The GLA has released consultation drafts of its new London Plan Guidance (LPG) on Affordable Housing and on Development Viability (4 May 2023).  The consultation closes on 24th July 2023.

There is a huge amount of detail to take in.

I am very grateful indeed to my Town Legal colleague Susie Herbert for what follows:


The updated LPG documents will replace the GLA’s 2017 SPG on Affordable Housing and Viability.  The new LPG comprises two documents with one covering Affordable Housing and the other covering Development Viability.  The Affordable Housing document covers the threshold approach, tenure, grant funding and build to rent while the Development Viability document covers the viability assessment process, principles for undertaking viability assessments, viability assessment information, inputs and sense checking, the review mechanisms and the formulas.

While much of the draft is similar the 2017 SPG with updates to reflect the 2021 London Plan and and to incorporate other guidance that has been released in the interim (such as the 2018 Practice Note on Public Land), some of the proposed changes are of more substance.

These include much more detailed guidance on the process for and the inputs to viability reviews covering a wider range of inputs which suggests a more prescriptive and standardised approach, including more emphasis on optimising the viability of the development including exploring different testing alternative uses; a suggestion that financing costs should be treated differently for different types of developer, and an exclusion of risk items of development costs such as Rights of Light costs or asbestos removal.  It is also made clear throughout the guidance that any public subsidy should be included in the development value but that the target return should not be applied to any public subsidy. 

There is also more prescriptive guidance on section 106 agreements and to monitoring requirements for both applicants and LPAs with information to be reported to the Planning London Datahub.

There is a more prescriptive approach to mid-term reviews which are now expected for schemes over 500 dwellings as well as those expected to have a build programme of more than 5 years or for estate regeneration schemes.  Any surplus return identified in a mid-stage review is expected to be used to deliver affordable housing.

In respect of early stage reviews, the draft guidance effectively rules out force majeure clauses so that the early stage review will apply whatever the reason for delay. 

Turning to eligibility criteria, there is a greater emphasis on provision for key workers and the consultation also states that the GLA is considering raising the £60,000 threshold to £67,000 and comments are invited on this. 

While the threshold approach remains in place, there is a change in respect of scheme changes which will allow schemes which were originally subject to viability review to follow the fast track route in respect of additional dwellings if there additional dwellings include enough affordable provision to meet the relevant threshold.  

While co-living will generally be subject to viability review, there is the potential for it to be assessed under the fast track route if it provides affordable housing meeting the internal space standards and the requirements of policies H5 and H6.

The consultation questions generally ask for comments on and suggestions for improvement for the various sections although there are some specific questions in particular in respect of income caps for intermediate housing. 

Affordable Housing Document

Threshold approach

The “threshold approach” first set out in the 2017 SPG remains.  This means that the Fast Track Route (FTR) is available for schemes with the minimum of 35% or 50% for public-sector land and industrial sites where there would be a net loss of industrial capacity although the 35% no longer states that it has to be achieved without public subsidy.

There is a change compared to the 2017 SPG in respect of scheme changes for developments that did not qualify for the FTR.  Previously any changes would also be subject to viability review but the draft LPG now suggests that if the proposed change is to increase the number of dwellings and that increase would include enough affordable housing meet the relevant threshold, then the FTR is available for the application to make the change to the scheme (paragraph 2.8.3).

The list of applications for which the FTR is specifically expressed not to be available and which must be subject to the Viability Tested Route (VTR) has also been expanded compared to the 2017 version to include co-living (large-scale, purpose-built, shared-living accommodation (LSPBSL) (in accordance with Policy H16) and also applications “where other relevant policy requirements are not met to the satisfaction of the LPA or the Mayor” which reflects Policy H5 C 3).  There is further guidance on this at Appendix 2 of the draft LPG which does allow for the possibility of the FTR for co-living if it provides sufficient affordable housing.


The draft LPG states that the Mayor’s preferred affordable housing tenure for low-cost rented homes is Social Rent and not London Affordable Rent as only Social Rent homes are eligible for grant funding under the London Affordable Homes Programme (AHP) 2921-26.  This is slightly different from the London Plan 2021 which lists both Social Rent and London Affordable Rent as preferred affordable housing tenures (para 4.6.3).

Eligibility for intermediate housing

In terms of eligibility for intermediate housing which is currently subject to a maximum income cap of £60,000, the consultation survey states that the GLA is considering raising the income cap to £67,000 in line with changes to median incomes in London since 2017.  Consultees are asked whether they agree with this and to provide comments.

The London Plan requires that intermediate housing is provided for a range of household incomes below the maximum caps for the first three months of marketing. The survey states that the GLA is considering setting out income levels below the maximum level which would apply where the relevant local planning authority has not published local income levels and the survey asks for views on whether this would be a helpful addition to the guidance.


The section on London Living Rent (LLR) states that rents should not be increased above the rate of the CPI including housing costs within tenancies and that on re-let the rent should revert to the LLR (or lower).  It also states that if no tenant has purchased their current home within 10 years, the RP may sell the home to another eligible purchaser on a shared ownership basis.

Key workers

The draft LPG also “strongly encourages” local authorities and housing providers to prioritise key workers when setting eligibility and prioritisation criteria.


The guidance covers the new model for shared ownership (SO) homes introduced by the Government in 2021 (which allows for the initial share to be a minimum of 10% rather than 25%) and confirms that only the new SO model homes will be funded by the AHP 2021-26 so the Mayor will expect SO homes to be provided on that basis.

Service Charges

The draft LPG contains a section on service charges which states that Applicants, LPAs and affordable housing providers should ensure that service charges are affordable for residents, and that they do not exceed the cost of the services provided. It also states that applicants should consult with affordable housing providers at an early stage to minimise service charges as part of design and management strategies.

The LPG also states that residents of affordable housing should be given the same rights of access to amenities and facilities within the scheme as occupiers of market housing at no additional charge other than service charges. If an LPA agrees that access to a facility would make service charges unaffordable for residents of affordable housing, this should be excluded from standard service charges and they should be given full optional rights of access at a fair and reasonable charge.

Key features document

A key features document should be provided to potential tenants and purchasers at the start of the marketing period. This should include detailed information on the tenure of a property and the length of any lease, as well as the full range of potential costs, including any expected service charges, permission fees and any other charges (including those relating to resales).


The draft LPG describes how the Mayor’s grant funding powers work alongside the threshold approach and describes the AHP 2016-23 and 2021-26.  In terms of maximising delivery, the FTR is available where an applicant commits unconditionally to provide at least 40 per cent affordable housing with grant (or 50% on public or industrial land).  However, if the s106 will allow for a lower level of affordable housing than the relevant threshold if grant is not available, the scheme must follow the VTR.

If grant is not available at the application stage but grant funding subsequently becomes available, the S106 should require that the level of affordable housing proposed in the grant application is provided.

Build to Rent

The BtR section has been updated and reflects the London Plan 2021 Policy H11.

Securing delivery

There is a new section on securing delivery which sets out what a section 106 agreement should include such as restrictions on occupation and ensuring that affordable housing is not concentrated in final phases.  It states that the affordable housing should be sold to an RP on a freehold or long (990 years) leasehold basis.  The section 106 agreement should secure obligation in line with the LPG and the Mayor’s standard section 106 clauses such as eligibility, affordability and review mechanisms.  The section 106 should also provide for the recycling of subsidy in the event that a home is no longer provided as affordable housing.

Monitoring and implementation

There is also a section setting out the applicant’s and the LPA’s responsibilities in respect of monitoring and implementation. The applicant should submit information on the affordable housing to be provided and the outcome of any viability review in a standardised format specified by the GLA.

The section also expands on the requirement under London Plan Policy H7 for boroughs to have clear monitoring processes with annual publication of monitoring information.  It is strongly recommended that this monitoring is undertaken by specialist officers or teams wherever possible and the costs of this should be met by applicants.

Development viability

Principles for undertaking viability assessments

The guidance in Section 3 on the principles for undertaking viability assessments is significantly more detailed than the equivalent sections in the 2017 SPG.

There are also additional sections on:

(a) how viability assessments should be objective and realistic with requirements for assessors;

(b) modelling sensitivity testing of assumptions and inputs and value growth and cost inflation;

(c) optimising the viability of development with detail of how applicants should demonstrate that the proposed scheme optimises site capacity through a design-led approach which may include testing different residential typologies such as BtR and build for sale; and

(d) sense-checking.

The consultation survey asks whether the approaches set out in these sections are practical and will help to ensure that viability assessments are robust.

Viability assessment information, inputs and sense-checking

Again there is further additional detail on the inputs for the viability review compared with the 2017 SPG including on affordable housing values.  This section also includes new detailed guidance on sales values, investment values, commercial property, grant and public subsidy, development programme, finance costs and other development costs. There is also a further section on sense checking.

Review mechanisms

Early Stage Reviews

In respect of Early Stage Reviews, there is a new paragraph on substantial implementation which makes it clear that provisions that seek to delay the trigger date for an Early Stage Review should not be included in the section 106 agreement.  The reasoning is that the review is intended to secure additional affordable housing where viability allows, regardless of the reason development may have been delayed.  This means that force majeure clauses which had sometimes been agreed to in light of the disruption caused by the pandemic will no longer be accepted. 

There may be more flexibility on the definition of substantial implementation as the paragraph now makes clear that the description of works is an example of substantial implementation rather than a definition of it.  

Where a payment in lieu of on-site affordable housing is made following an ESR, the guidance states that this can be included as a cost in subsequent reviews.

Mid-Term Reviews

The 2017 SPG stated that LPAs should consider mid-term reviews for larger developments that will be built out over a number of phases.  This is expanded in the draft LPG.  The draft guidance states that Mid-Term Reviews should be provided for larger phased schemes including those that propose 500 or more residential units (or for mixed-use schemes, the equivalent amount of development in floorspace) and that there may be other circumstances where Mid-Term Reviews are required for example where the construction programme is five years or longer or for estate regeneration schemes. 

The timing for Mid-Term Reviews is to be agreed with the LPA or the Mayor as applicable. For outline or hybrid schemes it may be appropriate for reviews to take place as part of reserved matters applications to enable affordable housing to be included within the design of the relevant phase or future phases.

Mid-Term Reviews should assess the scheme as a whole, taking into account actual values and costs for earlier phases, and estimated figures for subsequent phases.  They will not be conditional on reaching a specific level of progress by a trigger date.

Terms of viability review mechanisms

This section sets out more detail on the terms of VRMs to be included in s106 agreements.  This includes that any public subsidy is included in the development value figures but that the target return should not be applied to any public subsidy.

For Mid-Term Reviews, the guidance states that it is most appropriate that they follow Early Stage Reviews in that any surplus return should be applied to the delivery of affordable housing.  For Late Stage Reviews it may be acceptable for an element of surplus return to be retained by the applicant but not exceeding 40%.

There is also an additional requirement to ensure reporting of information to the Planning London Datahub on the number and tenure of affordable housing by unit and habitable room secured in the application and the outcome of reviews including additional affordable housing, changes in tenure and any financial contributions.

The Formulas

Formula 1a – this is unchanged except for a note which states that the review GDV and build-costs figures should include the commercial component where relevant.

Formula 1b – the note now clarifies that the application and review stage GDV figures should include any public subsidy that is available at the time of the assessment but this should be excluded when calculating developer return.

Formula 3 on late stage reviews contains additional guidance on how the assessment should be adjusted for BtR if they were originally assessed as build for sale.

There is a new Formula 5 for Mid-Term Reviews based on Formula 2 but using actual values and costs for completed parts of the development at the time of the review and estimated figures for the rest of the scheme.

There is also a new Formula 6 for converting affordable housing to a more affordable tenure.

The specific BtR formulas from the 2017 SPG (Formulas 5 and 6) are not included.

In terms of viability deficits, the draft guidance states that deficits should not normally be accounted for in review mechanisms and should only be allowed exceptionally where agreed by the LPA (and the GLA). Deficits should not be included in reviews for schemes that have followed the FTR.  The extent of any deficit should be determined by the LPA and the Mayor. A breakeven appraisal can be undertaken at application stage to assess the level of GDV and build costs at which the RLV equates to the BLV. The breakeven GDV and Build Costs should replace the application-stage GDV and build cost figures in the formulas.

Thank goodness we have a long weekend to take all this in! I’ll be testing you on Tuesday.

Simon Ricketts (with thanks again to honorary guest blogger Susie Herbert), 6 May 2023

Personal views, et cetera

Author: simonicity

Partner at boutique planning law firm, Town Legal LLP, but this blog represents my personal views only.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: