top of page

The Carbon In New Housing

Deriving Housing Need

The Ministry of Housing, Communities and Local Government has recently clarified that the methodology for determining housing need should continue to use ONS 2014 population data as one its inputs, despite the fact that ONS projections using 2018 population data are now available.

TTL had hoped that if the latest, lower, population forecasts could be used to assess housing need, NHDC would have been able to reduce the amount of green belt that will be lost as a result of implementation of the proposed North Herts Local Plan. However, if planning must continue based on 2014 projections it would seem the fate of North Herts green belt depends on whether the local plan inspector is persuaded that exceptional circumstances exist for removing large areas of green belt. A number of representations made at the hearings identified opportunities for development off the green belt which had not been properly explored.

TTL are concerned at the lack of robustness of the published methodology for calculating housing need. In particular the published method:

  1. is based on increasingly out of date population and household projections, projections which have methodological issues that have been addressed in more recent population projections.

  2. relies on an affordability adjustment which, although influenced by the level of suppressed household demand, is also highly influenced by the extent of wealth inequality in our country.

Buying homes to rent has become an attractive investment opportunity for those with spare capital compared to other investment options. Until recently young people could get a mortgage and gradually use their income to acquire the asset of a house. Now, they must increasingly compete with ‘investors’ to try and buy a property (competition which will have pushed prices up). Once an investor obtains a home, the rental market stock increases and the owner occupied housing stock reduces. More and more people are having to use their income to pay rent, rather than use it to pay off a mortgage and acquire an asset. Until a way is found to tackle excessive houses being purchased to rent it seems highly inappropriate to use house prices as a proxy for suppressed demand in housing need assessments.

New census data should give information on the extent of suppressed households, and we would suggest that it is population data, with details of who is residing in properties, that should be  used in place of the affordability factor in the methodology to determine housing need.

Future Homes Consultation

The government has recently published the results of the first stage of its Future Homes Standard Consultation. TTL took part in the initial consultation and we are pleased to see that:

  1. fabric energy efficiency performance measures are to remain

  2. local authorities have been given the ability to set higher standards in the period prior to the Future Homes Standard being introduced.

Looking at the analysis of responses there seems to be a clear message that the majority of respondents wanted to see the government make more progress to zero carbon homes in the Part L 2021 amendments than the government is planning. The government chosen option seems to fall short of mainstream opinion. Walls and floors are some of the hardest elements to retrofit, so it’s particularly disappointing that the 2021 update has been set with unchanged expectations around the U values for these building elements. For approximately 2cm more insulation in walls and floors, homes would be insulated to zero carbon levels for these building elements.

The Goldsmith Street development in Norwich demonstrates that affordable, zero carbon homes are deliverable now, so why is the government waiting until 2023 to start the Future Homes Consultation that will finally deliver building regulations for zero carbon homes in 2025? If we are to build back better, then surely, this consultation should start now.

Councils and Government showing Zero Carbon Home Leadership

Norwich council have shown in their Goldsmith Street development that it is possible to deliver affordable, passive houses  We have asked some questions about the cost, build process and ease of use by residents for this development.

Question: Were these houses were particularly expensive to build compared to your bulk standard housing developments?

Answer: “We have yet to get to final account but believe that the properties were of exceptional value for money. The construction cost was approx. £1875/m2 and all in cost approx. £2,200/m2. We believe that this is approx. 5-10% above a standard house but it is difficult to ascertain on this scheme what the additional Passivhaus cost was v the cost of great design.”

Question: Did it need specialists who were capable of delivering passive house build quality (its often found that build quality is poor in new houses with gaps in insulation and poor fitments leaving draughts) or were the houses built in a ‘factory’ and delivered to the site – a method that is known to improve build quality?

Answer: “The scheme has planning permission for 105 homes and to date 93 have been delivered – a second phase is planned once some rights of way issues are resolved. The council had procured a framework of contractors who all had experience of Passivhaus or higher levels of the Code for Sustainable Homes.  RG Carter were the main contractor for the project and they also delivered a close by Passivhaus scheme called Carrow Breck. Build quality is one of the benefits of Passivhaus as it is rigorously tested throughout construction and we linked payment to the passing of 3 air tests during the build. There is no performance gap with Passivhaus that there is in standard build or other standards. Goldsmith Street was build utilising a timber frame system by Cygnum that was part built offsite in a factory and this is something we are exploring further with a potential modular scheme.”

Question: It would also be interesting to know if the council have any feedback on how residents of these houses have found them. Have they been able to reap the benefits of a passive house in terms of reduced energy costs? For example, if there is mechanical ventilation is this being used or are windows and doors being left open with the heating on?

Answer: “We have not yet sought formal feedback from residents on this but have picked up some anecdotal comments from when we have visited the site. One resident who moved in November 2018 advised in April 2019 that she hadn’t had the heating on at all. I know that our lettings team do take some time explaining about Passivhaus when they sign tenants up to the property.”

Norwich Council have shown that councils and National Government have an opportunity to lead by example, when development is to take place on land they own, through commissioning homes that can operate as zero carbon, without modification, as the electricity grid de-carbonises.

From FOI questions we have identified the North Herts Local Plan sites where either NHDC or HCC have ownership. A total 3839 homes are planned to be delivered on these sites, 25% of the homes planned to meet North Hertfordshire needs. 3632 of these homes are on land owned by HCC and 181 on land owned by NHDC and 26 on a site which both NHDC and HCC have ownership.

The Crown Estate represented East of Luton sites at NHDC local plan hearings. Could the Crown Estate put in place a policy to only commission zero carbon homes?

To move the building industry on as the government wishes we need some early adopters to lead the way and surely the government and councils should be some of those early adopters. Can we persuade our local MPs and councils to only commission homes capable of operating at zero carbon on land they have put forward for new homes?

Related Posts

See All


bottom of page