South-facing lean-to conservatories can be optimised as a thermal buffer to the exterior wall and act as a passive solar heat collector, especially in spring and autumn. But using a heater in them is not a good idea! See sunspaces
How you can save energy now!
Funded by Suffolk's Public Sector Organisations, Suffolk Energy Assessment can come and assess your home - click here
| How much energy am I using? | per hour | per 10 mins | per hour | per 10 mins | ||
|---|---|---|---|---|---|---|
| Electric shower (9000 W) | £3.06 | 51p | Vacuum cleaner (900 W) | 31p | 5p | |
| Immersion heater (3000 W) | £1.02 | - | Dehumidifier (500 W) | 17p | - | |
| Kettle (3000 W) | - | 17p | Towel rail (450 W) | 15p | - | |
| Tumble Dryer (2500 W) | 85p | 14p | Plasma TV (350 W) | 12p | 2p | |
| Electric heater (2500 W) | 85p | 14p | Fridge-freezer (300 W) | 10p | - | |
| Oven (2100 W) | 71p | - | Freezer (150 W) | 5p | - | |
| Washing machine (2100 W) | 71p | - | Fridge (150 W) | 5p | - | |
| Oil-filled radiator (2000 W) | 68p | 11p | Heating blanket (150 W) | 5p | 1p | |
| Hairdryer (2000 W) | - | 11p | Desktop computer (140 W) | 5p | 1p | |
| Hob (2000 W) | 61p | 10p | Games console (120 W) | 4p | 1p | |
| Grill (1500 W) | 51p | 9p | LCD TV (120 W) | 4p | 1p | |
| Iron (1500 W) | 51p | 9p | Laptop (50 W) | 2p | - | |
| Toaster (1000 W) | - | 6p | TV box (40 W) | 1p | - | |
| Microwave (1000 W) | 34p | 6p | DVD player (40 W) | 1p | - | |
| Electric mower (1000 W) | 34p | 6p | Extractor fan (20 W) | 1p | - | |
| Vacuum cleaner (900 W) | 31p | 5p | Broadband router (10 W) | 1p | - |
Thinking about ways to save money and the planet
Some things need doing even before installing a heat network. Saving energy is probably the most important. There's
Get in touch by emailing info@heatingbildeston.uk or telephoning 01449740876 to see if our volunteer team can advise you. See news for more.
Basic ideas - DIY energy saving
According to the Energy Saving Trust, "Draught-proofing is one of the cheapest and most effective ways to save energy – and money – in any type of building."
One source is here. They also have a rather good house energy audit you can fill in.
Your energy supplier
According to Which? cheap energy deals have disappeared over the last several months so it's not a good time for most people to switch energy provider.
Replace light bulbs to save £180
LED lights cost around £1.71 a year to run and last 25 years.
Install and use central heating controls and save £75
Put on a jumper rather than turning up the heat.
Cooking with a microwave uses up to 90% less energy than an oven
As long as they're suitable for what's being cooked.
Low Cost - Secondary glazing
Cheaper than double glazing and ideal for historic building conservation areas. You get what you pay for, with better performance coming at a cost, although magnetic strip plastic glazing claims to equal double glazing. There's polystyrene, cheapest but yellows with age, acylic, doesn't yellow but is brittle and Polycarbonate, most expensive and very tough. Links - Ipswich Easyfix The Plastic People the Eco Experts
Thermal blinds, shutters and curtains
Masses to choose from, but they need to be sealed all round to be effective.... links - blinds, shutters, curtains
Buy an energy efficient appliance
Although a clothes dryer is a better idea than a tumble dryer.
Retro-fitting - Buying improvements
We're now getting beyond low cost, and there are a lot of caveats here. Link - reduce heat loss
Find out if you could get energy efficiency grants or free cash
Which insulation?
Glass foam is very expensive but is a structural material, Aerogel is viable if bought from China and Cellulose fibre is the cheapest and greenest but you need quite a lot of it. PIR board isn't the greenest but has the best cost/performance. Insulation types vary massively; some can't be used externally, some absorb water and some need special handling. Information varies but here's some links, Greenspec Wikipedia. Harder to find are comparison prices and environmental qualities.
Some actions are more worth it than others, according to Leeds Sustainability Institute, Demonstration of Energy Efficiency Potential, 2021,
Observed reduction in heating energy & Factors affecting performance
- Loft Insulation 3.9 % - 17 % Difficult to reach eaves, disruption from storage and maintaining services.
- Windows & doors 5.6 % - 15.3 % Failure to adequately resize openings, thermal bridging at frame and wall.
- Cavity wall insulation 7.3 % - 15.5 % Mortar snots and cavity debris, moisture penetration, problems with pre-existing partial fill insulation.
- Solid wall insulation 13.2 % - 68 % Thermal bridging, discontinuities in insulation layer, infiltration bypassing insulation, complex detailing, incomplete coverage.
- Suspended ground floor insulation 8.8 % - 25 % Existing infiltration paths, thermal bridging at ground floor perimeter, ground floor conditions
- Multiple measures 12.1 % - 20 % Different combinations of measures installed, interaction of measures, design team approach.
- Whole-house retrofits 35 % to 56 % Different combinations of measures installed.
Solid wall insulation is surprisingly beneficial but difficult to do well. Retrofitting is better still, complex but well worth it we're told.
Retrofitting
Retrofitting is the whole house approach to energy conservation. It can be costly, but it adds to the property value, is holistic and is the most efficient way of reducing greenhouse gases, providing comfort and saving money. Here's an example, a 1990s terrace house retrofitted by Penoyre & Prasad, architects.
To demonstrate the improvements that a whole-house retrofit can have on the energy efficiency of existing housing stock, Waltham Forest Borough Council appointed the Aston Group to manage the retrofit of 47 Greenleaf Road, a typical 1902 terraced house, into its first-ever eco show home. The Council currently has the third-highest rate of fuel poverty in London. As fuel prices rise, this trend is set to continue, unless action is taken. The Council are actively looking for ways to address this issue including whole-house retrofits. Retrofits create warmer, more energy-efficient and comfortable homes.
Annual Annual CO2 Costs
energy use emissions (£/year)
(kWh/year) (kg/year)
Original building 29,471 6,596 £1,580
Refurbished building 4,654 945 £435
Improvement 84% 86% 72%
Tested performance 5,257 1,258 £568
Adjusted 82% 81% 64%
There's a detailed report of what was done here.
There's a guide from not-for-profit social enterprise Trustmark, available here which mentions the new British Standard for energy efficient retrofitting, PAS 2035. It's mandatory for companies who do retrofitting work and involves qualified advisors, assessors and designers. An overview of the standard is here.
Experts in retrofitting, all 98 of them, have built on the standard and produced a guide for designers - it's 208 pages long. You can download LETI Retrofit Guide here or take a look at the Quick Start or the Typical house types guide. It gives an idea of the thoroughness that is needed to adapt old houses for the climate emergency.
Special cases, for historic timber framed houses, see Historic England.
As loft insulation in isolation is not effective and as walls need breathabilty, wall insulation (replacing the infill panels), is limited to hemp-crete or hemp & lime or wood-fibre & lime plaster. Not for d-i-y. Internal insulation can be wood fibreboards or cellulose, either loose fill or blown onto studs, with a plasterboard finish. The performance is limited by the wall depth and/or the amount of lost interior space, but the improvement in air-tightness is likely to be significant. Hempcrete has been used on Grade 2 listed buildings and has been highlighted by English Heritage and Society for the Protection of Ancient Buildings. See Hempcrete. Lime plaster with Aerogel is available. See Core Conservation.
One particular problem with houses built before about 1919 is that they rely on 'breathability' - their construction allows moisture in and relies on leaky walls and roofs to let large fires, the wind and sun dry them out again. Using modern impervious materials often causes dampness problems, so breathable insulation, usually more natural such as sheeps wool or hempcrete, becomes essential.
A major constraint on upgrading historic buildings has been restrictions on window replacement. Vacuum double glazing with very thin units (around 6-8mm) have been permitted but are expensive (upwards of £250/m2). There are 2 brands, Landvac and Fineo. Secondary glazing, behind the original widows, is more affordable, but less energy efficient. See this blog and this comparison.
Retrofitting or conservation?
Extensively upgrading our houses is really about saving the planet. The UK is legally bound to a target (Climate Act 2008) to reduce carbon emissions by 80% of 1990 levels by 2050. And heating buildings is 30% of the emissions total. That means every single house has to improve by something like 25%. Or, more likely, many are going to have to be very energy efficient.
There's already a standard that goes beyond PAS 2035 called EnerPHit, based on the ultimate low-energy building standard, Passivhaus. It can mean efficency is so good that central heating is not required at all.
But with conservation planning inspectors resisting the use of triple glazing and arguing for more modest approaches, there's a growing tension between conservation and retrofitting that will probably intensify as the climate emergency becomes ever more desperate. While there's no doubt retrofitting has to be not just fabric-first but whole life costed and not an excuse to rebound and have higher indoor temperatures, it's also true that hanging onto the past unreasonably could cost us a planet out of control. See our blog for more debate. There's a good guide to retrofitting your home available here.
Architects Climate Action Network
'Climate Emergency Conservation Area Toolkit' aims to provide a methodology with a worked example to update Conservation Area Guidance which will allow more complete Climate Emergency Retrofitting. It addresses aspects of retrofitting heritage and non-heritage in Conservation Areas which involve planning. These are generally exterior building changes that impact appearance of the Conservation Area.
With 20% of total UK carbon emissions coming from our 29 million existing households there is an urgent need to reduce carbon emissions in all housing stock including Conservation Areas. The 2021 ‘LETI Climate Emergency Retrofit Guide’ estimates that heritage or architectural constraints involve 25% of all UK homes.These heritage or architecturally constrained homes emit more carbon than typical homes, therefore at quarter of all homes they contribute more than 5% of total UK Carbon emissions. This is a percentage that can’t be ignored on the road to Net Zero nationwide. Architects Climate Action Network
2023 was the hottest year on record. In 2015 the UK Government signed the Paris Agreement to limit global warming to 1.5°C compared to pre-industrial levels. Any increase beyond this will set in motion irreversible changes to the climate. On current trends, the world is likely to reach 1.5°C in the next few years and we are heading for 3°C temperature rise by 2050 at best.
‘We will not meet our targets… without near complete decarbonisation of the housing stock'.
The Decarbonise Your House Now! guide hopes to give you all the inspiration you need to undertake
sustainable renovations and upgrade your house for the zero carbon future.
It is researched, written and designed by Editional Studio, an architecture and design practice based in Manchester, UK.
