Written evidence submitted by Mr. Jason West, director of Weyforward CIC on behalf of


Is the Answer an Extra Bedroom?


Executive Summary


        The Chair of the Climate Change Committee directly contributed to this submission

        Old housing stock is our biggest environmental problem

        Around 20% of UK housing was built before 1920

        Lack of good housing and energy inefficiency are directly connected

        Adding usable space to old houses and making it a generator of renewable energy can make an old house net zero carbon and facilitate the transition from gas to electric water and space heating




Weyforward CIC is a local non-profit organisation with the mission to educate and regenerate Weymouth & Portland in Dorset. Jason West is a founder and director of the company who wanted to make a real difference when retrofitting his 1890s mid-terraced family home in 2017/18. The renovation avoided using costly passive/enerPHit building methods but still achieved a net zero carbon outcome.


1.              “This is precisely the kind of change that we are going to need to do if we

want to win the battle against climate change.”


Statement from Rt Hon John Gummer, Lord Deben to the Weymouth & Portland Borough Council Planning Committee of 11th January 2017 in support of a planning application to retrofit a mid-terraced 1890s house. The application was eventually successful and the Solar PV House is now an example of what can be achieved with old housing stock, some determination and a little imagination.


2.              29% of UK housing stock is old,  it is our biggest problem and looks like this.



Figure 1.



3.               English Housing Survey Housing Stock statistics:


37% rented, 29% terraced, 22% in city/urban area, 20% built before 1919

Usable floor area 25% smaller in private and social rented

Rented homes have fewer rooms.


4.               How to add usable space to old terraced houses.

See Figure 2.




Figure 2. (© Patrick Cray)


4m social housing dwellings could do with more space (29% terraced) and 4m private rental dwellings could do with more space (29% terraced).


If half of all rented properties had a new bedroom dormer clad on three sides with 20 of PV + battery storage = 80 of solar...they would power 10% of the UK based upon the Greenpeace estimate of a total solar power area of 827 to power the whole of the UK. That’s an area of roofing equivalent to 21% of the area of the Isle of Wight.


Our planning system can provide an all encompassing solution to our biggest problem by allowing old buildings to generate more renewable energy using PV clad dormer extensions.

Copy of Rear_elevation_solar_membrane_area_in_red_square.pngmain_and_side_dormer.jpg

Figure 3.


5.              A pre-1920 now electric only house can currently be powered at a lower per kWh unit price than gas using PV + storage + dynamic pricing/smart device management. The current average gas price is 3.8p per kWh. This electricity bill (Fig.4 below) is from the 1890’s terraced house that Lord Deben said was “the kind of change we are going to need to do”. It is situated in Weymouth, Dorset.















Figure 4.


6.              House Statistics:


Energy Comparison

Victorian terraces                                          421.5 kWh/m2/year approx.

Passive retrofit in Kensal Rise London              15 kWh/m2/year

Superhomes (Energy Saving Trust)               104 kWh/m2/year

UK average according to Superhomes              177 kWh/m2/year

SolarPVHouse                                           (predicted)              53 kWh/m2/year

(recorded over period) 73-86 kWh/m2/year (likely adjusted actual) 65 kWh/m2/year

Carbon Comparison

Superhomes                                                                      60% reduction to qualify

SolarPVHse Co2 Emissions Reduction              Over 75%

(maybe just under 100% as all electric renewable/stove burns 50% coffee logs which reduce methane emissions from landfill)

SolarPVHouse Co2 Emissions Rate              7.51 Kg/Co2/m2/year

(stove wood/some elec but doesn’t include coffee logs which reduce landfill methane from coffee grounds by 80%)

SolarPVHouse Changes

Energy Efficiency                                                         ‘F’ EPC to ‘B’ (predicted) high ‘C’/low ‘B’ (actual)

(mitigating factors old front door/no green roof/digital teenagers, ‘comfort taking’ with stove)

Environmental Impact                                                        F’ to ‘A’



7.              If the UK’s old housing stock were improved in this way it would involve the creation of an area of solar PV 21% the size of the Isle of Wight but would increase housing density, protect the green belt, power 10% of the UK based upon the Greenpeace estimate of a total solar power area of 827 to power the whole of the UK  (which would have hit 2020 renewables targets), inject around £100bn into the economy creating jobs whilst generating around £20bn in VAT whilst 38% of private landlords will spend in excess of £10k when they acquire a property and 18% will spend in excess of £20k. Main reason? To increase capital value and rent (Source: Univ of Cambridge 2014) See Figure 5. Below. Plus 2 million extra bedrooms would create the accommodation equivalent of 500,000 new four bedroom houses.



Figure 5.


Can an extra bedroom have any wider impact than the house it is on?

BuildTeam-loft-conversion-2-velux.jpgYes it can.


May 2021