Top Ten Tips for Moving Home Efficiently

moving home

Advice for an Efficient Home Move

It is often said that after death and divorce, moving home is life’s biggest cause of stress. Fortunately if you plan ahead and follow these top tips, the potential for things to go wrong can be greatly reduced.

1 De-clutter your life

We all accumulate possessions that we do not really use or need, but it seems a shame to throw them away. 

Time to be harsh!  If you have not been using them, you probably never will and the period leading up to moving home is an excellent time to sell or recycle them.

Aim to de-clutter one room at a time, not forgetting cupboards and drawers. Start with the loft or garage, as these may present the greatest challenge!

2 Use a professional

Give serious consideration to getting the packing and removals done professionally, especially if you work full time.  It may seem an unnecessary cost at a time when you can least afford it, but it is not always as expensive as you might think, particularly for moving home locally.

3 Stockpile boxes and pack early

If you are going to do the move yourself, start to collect boxes and packing materials early. It is often possible to identify items that can be packed many weeks in advance of moving home. The more you can do in advance, the less intense is the work and stress on the day.

4 Label all boxes carefully

Each box should be labelled with its contents and the room into which it needs to be delivered at the new house.  Put corresponding labels on the doors of all rooms in the new house if you are using a removal company or friends to help.

5 Pack a survival kit

Pack a survival kit with the essentials needed for the day of the move. Include maps, instructions, contact details, food and drink and anything else needed for the journey. Cleaning will be easier before you unload, so include the necessary materials and implements, including dry powder carpet cleaners.

6 Offload the kids and pets

Arrange for friends or family to look after the children and pets for the day of the move.

7 Arrange suitable parking

Make sure the removals van will have somewhere to park to load and unload without causing inconvenience. Upsetting new neighbours by blocking in their car is not a good introduction to an area!

8 Find the energy meters and fuse boxes

Ask the vendor about the heating system and thermostats and where the gas and electricity meters and isolators are before you move. Read the meters as you move out and in. Ask for details of the energy suppliers and review any recommendations from the EPC survey for prompt attention.

9 Ask the vendors those other critical questions

Compile a fact file for the people moving in to your old home and ask the vendors to put one together for your new property. Include the location of stopcocks, codes for alarms, details of refuse collection, recommended local tradesmen and other useful services. 

10 Round up the keys

Collect all of the keys to your house and leave them for the new owners with confirmation that there are none outstanding. Check that you have all of the necessary keys for your new home, and consider changing locks as soon as possible in case there are any stray keys still at large.

Lastly, don’t forget to get your EPC done.  You MUST have a valid one in place for the property you are selling when you are moving home.  If you’ve left it to the last minute don’t panic, Find EPC can often turn an energy performance certificate around at very short notice.

If you liked this article, check out some of the other titles from our blog page.

Top Tips for Selling Your Home

Are Conservatories Energy Inefficient?

Ground Source Heat Pump

European Directives on Building Energy Performance

Renewable Energy Keeps Getting More Popular

If you’d like to Book An EPC, fill in an online form or contact us on 0330 222 0019.

Ground Source Heat Pump

ground source heat pump

Ground Source Heat Pumps – Their Cost, Their Installation and Their Efficiency

Heating accounts for a significant portion of a household’s energy demand and a ground source heat pump system can provide a cost-effective and sustainable way to warm a home. The pump uses a small amount of electricity to transfer naturally occurring heat from the adjacent ground into the house.  As the temperature just a couple of metres below the surface remains more or less constant at 11°C to 12°C, it is possible to design a very efficient heat transfer system.

How does it work?

A sealed loop of fluid-filled pipe is buried in the garden or driveway. The length required depends on the size of the home and the amount of heat required. An average system for a family dwelling will typically require pipework up to 100m long.  Vertically drilled boreholes and deeper pipes can be used in more confined spaces. Once installed, the ground is restored to its original condition and the system becomes invisible.

The ground source heat pump circulates water and antifreeze around this loop. The fluid absorbs heat from the ground before it passes through a heat exchanger.  Energy is then transferred to the heating and hot water circuits of the home. The cooled fluid flows back into the ground loop in a continuous process for as long as the heating is required. Some systems can also be designed to meet cooling needs in summer.

While there are some minor residual energy and carbon costs, hooking the pump up to a home renewable technology such as a solar panel can increase its sustainability credentials even further.

What properties are suitable?

Ground source heat pump systems are not suited to every type of property. In general, they work most efficiently in well insulated homes with a relatively even and low heat demand. They produce heat at a lower temperature than more conventional central heating so a larger area is required for heat distribution. Underfloor heating is the ideal partner, though large heat pump system radiators are available. The system also requires sufficient outside space for installation. While minimal on-going maintenance is required, there can be considerable disruption during installation, and the system tends to be more attractive for new-build or as part of a wider home improvement project.

A typical domestic ground source pump is the size of a large upright fridge freezer. To save indoor space they can be installed in an outbuilding or basement.  They just need to be as close as possible to the end of the ground loop pipe. With a typical noise level of a little over 40dB at one metre away, they are as quiet as a fridge.  That’s considerably quieter than a typical gas or oil central heating boiler.

What do they cost and how much will I save?

Costs and savings will be dependant on the size of the pump, the length and depth of loop installation, the energy efficiency of the property, the sort of heating system that is being replaced and whether any additional work is required on the wider home heating system.  A typical domestic installation costs £12,000 to £15,000, with annual running costs of £600 to £700. At current prices, the payback from a ground source heat pumps is unlikely to represent an attractive alternative to an established mains gas central heating system. However, installers claim energy savings of nearly £1,500 annually for a typical four-bedroom house when compared with standard electric heating, or around £600 when compared to oil-fired central heating. That represents a saving of nearly 5,000kg of CO2 emissions each year.  Government Renewable Heat Incentive grants are currently available for installation.

Their installation will also greatly improve your energy efficiency score on your EPC.

If you liked this article, have a look at some of our other recent posts.

Property Size and Type and its Effect on Energy Usage and Your EPC

European Directives on Building Energy Performance

Top Tips for Selling Your Home

Comparing the Energy Efficiency of Modern and Traditional Walls

Waste Water Heat Recovery Systems (WWHRS) and your EPC

Are Conservatories Energy Inefficient?

Renewable Energy Keeps Getting More Popular

If you’d like to book an EPC for your home, simply contact us by phone or email, or fill in our contact form.

 

Top Tips for Selling Your Home

tips for selling your home

Top Ten tips for selling your home

Property websites and popular TV shows are full of wonderful theories about how to sell a home quickly and for the best price.  There have even been studies to observe the eye movements of potential buyers when they come to view a property to determine what they are really interested in. Here are ten of the top tips for selling your home.

1: First impressions

Potential buyers form lasting impressions of a house within seconds of arriving outside. Improve the kerbside appeal and ensure that the front garden, driveway and path are tidy and well maintained. Give gates and fences a lick of paint and make sure that the front door looks welcoming.  Put away or disguise refuse bins and use bedding plants to add colour to the scene. Window boxes, containers and hanging baskets all work well.

2: Clean and de-clutter

Dirt and clutter put people off properties more than anything else. Stained carpets, scuffed walls, grubby grout and any signs of damp or mould are all complete no-nos.  Hard floors should be shining, kitchen appliances spotless, and the bathroom and toilet must look and smell clean and hygienic.

Personal clutter may be meaningful to you, but it makes a house look smaller and less homely to others. Tidy up and make more space, paying special attention to kitchen work surfaces. Put the toaster, knife blocks and tea bag jars away in cupboards for the time being and leave worktops as usable areas.  Pack lounge and bedroom clutter away or put it into storage with any items of furniture that you do not really require to create more space.

3: Turn it neutral

Look for a balance between neutrality and personalisation. Make the paint schemes neutral, so that buyers will not be put off by your personal taste. Put away personal items that would not appeal to others but leave some personality, avoiding a bland property that looks like a chain hotel room.

4: Do those repairs

Even seemingly insignificant problems like a sticking door or a dripping tap remind potential purchasers of home maintenance chores.  Fix them, and don’t leave anything that you feel the need to apologise for when you show people around.

5: Light and mirrors

Put up mirrors to reflect natural light to make rooms and corridors seem more airy, larger and brighter. Put in brighter bulbs and leave them on if necessary during a visit. Place lamps strategically in dark corners.

6: Keep it warm

Always make sure that the property feels warm and inviting. Nothing is more unwelcoming than a cold, damp house. Use home energy efficiency measures to improve the property’s EPC rating and provide purchasers with a copy of the certificate.

7: Banish the smells

Bad smells are a real turn-off for buyers. Make sure the house is aired, empty the bins, bleach and rinse the drains, don’t smoke indoors or cook anything that might create lingering odours, and clean the carpets and curtains.  Put on clean bedding, and use a fabric freshening spray on beds and curtains. Air fresheners are useful, but do not use a strong fragrance or potential purchasers may think you are hiding something.

8: Remember the view

Views out of windows are important to many people, so clean the windows and tidy outside areas too. Cut the grass and hedges so that garden maintenance tasks are less obvious. Pressure wash paths and the patio.

9: Make rooms usable

If you have converted a bedroom into a magazine library or hobby room, convert it back to its original use. Others will not share your passions and need to be able to visualise their own use of the room. 

In a family home, make sure there is a clear, open-plan living space, taking off doors if necessary to demonstrate clear flow and function.

10: Set the stage

If all else fails, follow the popular advice and bake some bread, put fresh coffee on, have fragrant flowers in vases and fresh fruit in a bowl and place freshly laundered towels in the bathroom. The final touch? Borrow an expensive car and park it in the driveway. Some agents swear by it!

Our blog contains other articles relating to EPCs, home energy efficiency and tips for selling your home.  Here are some examples.

Comparing the Energy Efficiency of Modern and Traditional Walls

European Directives on Building Energy Performance

Renewable Energy Keeps Getting More Popular

Are Conservatories Energy Inefficient?

Property Size and Type and its Effect on Energy Usage and Your EPC

If you need to book an EPC or would like to contact us, please use these links.

Renewable Energy Keeps Getting More Popular

renewable energy

Renewables enjoy a rising wave of support

The UK Government monitors public attitude towards renewable energy technologies and climate change through a regular survey. The tracker was launched in March 2012 by the Department of Energy and Climate Change (DECC), now part of the Department for Business, Energy and Industrial Strategy (BEIS).

Known as the ‘Energy and Climate Change Public Attitudes Tracker’ (PAT), the main survey is carried out annually in March, with three supplementary short surveys in June, September and December. The repeat questions track the public’s views on important energy issues.  Each survey is known as a ‘Wave’ and the results of the Wave 25 survey were published recently. Wave 25 comprised 2,102 face-to-face, at-home interviews with a representative sample of UK adults. The background and detailed data are available on the UK Government website (here).

The latest survey results suggest a rising tide of public anxiety over climate change issues, with 74% of respondents saying that they were ‘very concerned’ or ‘fairly concerned’. The rise from 71% in May 2017 is a continuation of a growing trend. Perhaps due to on-going coverage in the media, a greater proportion of the public now accepts that climate change is the result of human activity rather than natural process. Just less than 50% said that they believed climate change problems were caused mainly by human activity, compared to only 10% who believed they were down solely to natural processes.

The latest Wave 25 results show overwhelming backing for renewable energy technologies, especially solar power and offshore wind farms. A comparison with the results from previous years reveals that public support for the use of renewable technologies to supply electricity, fuel, and heat has been climbing steadily.  It has now reached 85%, the highest recorded level since the tracker was set up. Only 3% were opposed.

In terms of the individual clean energy technologies, solar was given the greatest vote of confidence at 87%, with offshore wind reaching a record high of 83%. Close behind came wave and tidal power at 81%, onshore wind turbines at 76% and biomass power stations at 69%. The survey results also seem to indicate a reducing NIMBY effect, with people getting used to seeing and accepting large scale renewable projects in their own areas. 66% now say that they would be happy to have a development locally, compared to 58% in the same month of 2017.

By comparison, support for nuclear energy was largely unchanged over the year at 38%, with 22% opposed. The public’s attitude to shale gas extraction also remained essentially stable at just 18% in favour and 32% opposed.

The Wave 25 survey also included questions about perceptions of home energy efficiency.  Interviewees were asked what two things they thought use the most energy in the home. The answers included central heating (71%), large appliances (45%), and hot water (37%). When asked about home energy efficiency measures, 78% had installed double glazing, 65% loft insulation and 44% cavity wall insulation. Awareness of under floor insulation and solid wall insulation was much lower than for the other energy efficiency measures.

A question was also asked about home Energy Performance Certificates (EPCs).  63% were aware of EPCs, an increase over recent years, but only 9% claimed to know the rating of their own home.

It seems renewable energy is here to stay and will continue to play a greater role in all of our lives.

If you’d like to book an EPC, please feel free to contact us.

Like this blog post?  Please subscribe to our regular posts, here are a selection of other articles.

Property Size and Type and its Effect on Energy Usage and Your EPC

Are Conservatories Energy Inefficient?

European Directives on Building Energy Performance

Comparing the Energy Efficiency of Modern and Traditional Walls

Property Size and Type and its Effect on Energy Usage and Your EPC

EPC

Energy usage by property size and type

It’s a simple fact that large old detached houses have a lower EPC score than modern flats.

Logic suggests that, on average, larger properties will generally use more energy for heating than comparable smaller ones. However, there are many variables involved in such a calculation, not least of which will be the type of property. Flats tend to have fewer external walls and roofs than terraced houses, which in turn have fewer than semi-detached or detached houses. The larger the external surfaces, the greater the expected loss of energy. Other variables such as the age of the property, building materials and the effectiveness of energy efficiency measures that have been installed also confuse the picture.

So although there are a lot of things you can do to influence the score of your EPC, some things you can’t.

A large sample of households would be needed to make an analysis of energy need by dwelling type statistically reliable. The Government’s Home Energy Efficiency Database (HEED) provides such a data set. While not freely available to individuals, the information is available to researchers and organisations planning and monitoring progress in home energy efficiency. It includes information collected between 1995 and 2012 on some 13 million dwellings in the UK, almost half of the country’s housing stock. The data includes property age, type, tenure and energy use, and details such as glazing type, wall type, heating systems and energy efficiency measures.  All of which are fundamental to EPC calculations too.

Researchers at the Energy Institute of University College London were given access to the database to undertake a wide range of analyses, including an evaluation of average energy usage by dwelling type and number of bedrooms.  Their research is reported in the journal Energy Policy (Energy efficiency in the British housing stock: Energy demand and the Homes Energy Efficiency Database. Hamilton I.G. et al, Energy Policy 60 (2013) pp 462-480).

The researchers analysed the data to provide an overview of the statistics for gas and electricity use in 2006 by different types and sizes of dwelling. The following tables summarise their findings, giving the median value in each case (i.e. the mid value when all data are set out in increasing order of size), as they showed this to be a more representative ‘average’ than the mean. The figures for gas and Economy 7 tariff electricity are likely to be most representative of energy demand for heating.

Median energy use for different types of property

Type

Normal tariff  Electricity (kWh/yr) median

Economy 7  tariff  Electricity (kWh/yr) median

Gas (kWh/yr) median

Flat

1,967

4,309

10,242

Bungalow

2,784

4,828

16,129

Terraced house

3,038

4,845

14,983

Semi-detached house

3,310

4,765

16,571

Detached house

4,023

5,135

20,992

Median energy use for different numbers of bedrooms

Number of bedrooms

Normal tariff  Electricity (kWh/yr) median

Economy 7  tariff  Electricity (kWh/yr) median

Gas (kWh/yr) median

1

1,934

4,685

11,137

2

2,554

4,662

13,541

3

3,357

4,637

16,590

4

4,358

5,390

21,560

5+

4,890

6,171

24,246

As expected, the results confirm that detached houses and bungalows have the highest energy usage. The figures show a clear decrease in demand as the level of detachment declines, so that flats, with the highest number of party walls and ceilings, show least energy usage.  Something which EPC scores also make clear too.

The median gas demand increases on average by 22% for every additional bedroom over one in any property type. Overall electricity use also generally increases with additional bedrooms, though not as clearly and steeply as gas.

Waste Water Heat Recovery Systems (WWHRS) and your EPC

WWHRS

Hot water down the drain

The ways you heat, store and control your hot water is an important part of your overall EPC.  This article explores how to make the water we waste work for you and how that can have an impact on your EPC score

Heating water is an energy-intensive business and it is estimated that our daily showers consume more then half of the hot water that the average household produces. After it has done its job, that water will immediately exit the house and enter the sewerage system at around 35°C, depending on how hot you like your shower. That is a considerable amount of energy and money to lose down the plug hole. It is also a significant contribution to the damaging release of greenhouse gases, with domestic hot water heating being responsible for some 6% of the UK’s total CO2 emissions.

In many circumstances it is possible to recover some of this waste heat before it is lost down the drain.  Wastewater heat recovery (WWHRS) is installed in many new-build buildings with a high demand for hot water, such as hospitals, hotels and laundries. Domestic versions that can contribute to a higher EPC rating are available.

The energy can be recovered from the wastewater through simple heat transfer. The system is entirely passive, no energy input is necessary and there are no moving parts to maintain. Few properties lend themselves to the retrofitting of WWHRS to whole-house drainage, as the plumbing tends to be too complex. However, heat recovery systems can be connected to many types of domestic shower units, provided there is sufficient space and all of the relevant pipework is metal. A typical vertical WWHRS unit is approximately 2m high so installation may not always be possible. Horizontally fitting alternatives are available, though they are generally less effective.

Heat recovery from showers has a particular advantage. As the used water runs away, there is a simultaneous on-going requirement for further hot water, so no storage is needed. A shower is supplied from hot and cold water sources and if the cold input can be pre-heated using the waste heat, then less hot water is required in the mix to achieve the desired shower temperature.

Heat exchange is more efficient at lower flow rates, with around 60% of waste heat typically being recovered from a shower operating at a flow rate of 7.5 litres/minute through a typical modern vertical WWHRS unit. Horizontal units operate at around 45%. In practice, a vertical WWHRS unit working on an average shower with wastewater at 37°C should be able to transfer approximately 17°C of heat from the wastewater to pre-heat mains water heading for the shower from 10°C to 27°C.

The system works well with thermostatically controlled showers supplied by a combination boiler, with recovery-heated cold water feeding both the shower and the boiler: however, it is important to check that the combination boiler can accept pre-heated hot water. Some WWHRS are also compatible with unvented cylinder or electric shower units.

Typical cost savings are not great in the context of an installation cost of around £1000, though routine use in new build houses with purpose-designed plumbing systems is much more effective. A family of four each taking a daily five minute shower at a flow rate of 7.5 litres per minute uses a little over 50m3 of hot water a year. 35kWh of energy is needed to heat 1m3 of incoming mains water to 40°C at the shower head, so the family uses nearly 2,000 kWh in total. A conservative estimate of 50% efficiency in real life use means that 1,000 kWh of energy would be saved each year. Depending on the fuel and tariff, this represents a saving in the region of £100 per annum, or a ten year payback period. The payback period for a smaller family using less hot water will be considerable longer.  Your EPC rating however, will show an improvement.

European Directives on Building Energy Performance

energy efficiency

The European perspective on building energy performance

Whilst looking at your EPC and considering the energy efficiency implications for your home, consider the wider perspective.

In April, the European Parliament gave its final consent to a revised Energy Performance of Buildings Directive. This is a key plank in the European Commission’s intention to lead the transition to clean renewable energy and to create ‘a resilient Energy Union and a forward-looking climate change policy’.  Whilst maintaining a fair deal for all energy consumers. It is the first of a series of measures to promote the EU’s ‘Clean Energy for All Europeans Package’, and a major contribution to its commitment to cut carbon dioxide emissions by at least 40% by 2030.

The Directive looks to up the rate of building renovations to make them more energy efficient and to foster more use of smart automation and control systems to improve energy performance in new buildings. It starts a clear path towards the creation of a low emission building stock across the EU by 2050 and underpins national roadmaps to decarbonise buildings.  This directly affects you if you require a commercial EPC.

The concept of a ‘smart readiness indicator’ is introduced. This measures the capacity of a building to use new technologies and electronic systems adapted to the needs of the occupier, optimise their operation and to successfully interact with the grid.

The EU is looking to realise the massive potential for energy efficiency improvements in the building sector, which is responsible for some 40% of final energy use.  It estimates that approximately 75% of buildings are energy inefficient and capable of improvement.  The rate of building renovation varies by Member State, but overall only 0.4% to 1.2% of the stock is renovated each year.

These data also highlight the potential economic opportunities of the programme. The construction sector generates some 9% of European GDP and directly supports 18 million jobs. Building renovation work and energy technology retrofits add almost twice as much value as the construction of new buildings, and these areas are particularly important for small and medium-sized businesses. The proposals will also help to create jobs in the smart technology sector, combat energy poverty and save consumers money through the renovation of older, less efficient buildings, and improve quality of life.

The EU recognises that significant up-front investment is required for the refurbishment of buildings and that public and private financing will need to be mobilised. The Directive is supported by financial enabling tools to help achieve the necessary investments. This include revised Eurostat guidance for energy performance contracts and a ‘Smart Finance for Smart Buildings Initiative’. The European Fund for Strategic Investments has also been expanded. This is focussed on sustainable investments that contribute to the EU’s energy and climate targets and help to deliver the transition to a resource-efficient, circular and low-carbon economy.  At least 40% of the Initiative’s infrastructure and innovation projects are intended to contribute to the European Commission’s commitments to climate action and energy transition in line with the Paris Agreement objectives.

Following the formal agreement of the introduction of the Directive by the Council of Ministers and its subsequent publication in the Official Journal of the Union, Member States will have to transpose the new elements of the Directive into national law within 20 months. This will therefore be one of the first tests of the UK’s reaction to an EU Directive once Brexit has been achieved.

How will the energy efficiency of the UK be affected?  Will it have an affect on your EPC requirements?

Are Conservatories Energy Inefficient?

conservatory

Do conservatories conserve energy?

How does a conservatory affect your EPC?

While undoubtedly being great for providing additional light-filled living space, the question of whether conservatories are good for energy conservation is less straightforward.   Just how much is your conservatory costing you and could it have a detrimental effect on your EPC?

A conservatory is a popular and relatively cheap way of extending a home. If it has a floor area of less than 30sqm, a door that thermally separates it from the house and it is not connected to the house heating system, a conservatory is also generally exempt from Building Regulations Part L controls, and possibly also planning permission, depending on its position and the history of extensions to the property.

However, all too often the conservatory becomes a very costly addition when on-going heating bills are considered.  The cheapest, aluminium-framed conservatories of the 1970s and 1980s and those with polycarbonate rather than glass roof panels are particularly poor in terms of energy efficiency, and there is very little retrofitting that can be done to make significant improvements.

In the right place, conservatories are great for harvesting heat from the sun, but this can mean they become too hot in the summer while being very inefficient in the short and often cloudy days of winter. A south-east facing conservatory is generally considered best, as it will collect heat from the morning sun and be less prone to overheating during the warmest part of the day.

The positive side of the winter story is that a closed and unheated conservatory may provide a slight buffer to the rest of the house against cold weather, reducing the temperature difference between the main room and the outside by a few degrees. For this to be effective, the conservatory must be thermally separated from the main part of the house with solid, draught-proof doors, or glass doors with thick curtains. Thermal mass in the conservatory will store winter heat for longer, so exposed brick walls that catch the sun and a stone floor will absorb then slowly release the energy.

The downside is that many families need the conservatory as a living space year-round, and soon discover just how inefficient they are at conserving heat.  It is simply not feasible to insulate such an extensively glazed space sufficiently, so the only energy and cost efficient way to run a conservatory is not to heat it.

While a conservatory can never be brought up to the thermal standard of even an un-insulated cavity walled room, for a family that has no option other then to use and heat the conservatory there are measures that can help a little. Modern double-glazing with ‘Four Seasons Glass’, blinds and shutters can all help to reduce the amount of wasted energy.

A more radical solution is to replace the glazed roof with solid, insulated panels. The situation in relation to planning permission and Building Regulations should be checked. Installers claim that modern panels can be up to eight times more efficient than a polycarbonate roof, and some fit ‘multifoil’ insulation which is very efficient at heat deflection in the summer while helping to protect against damp and condensation in the winter. This is said to reduce the hottest summer temperatures in the conservatory by 70% and make it 90% warmer in the winter. While such figures sound impressive, the conservatory will nevertheless still suffer a very significant loss of energy through the winter if heated.

Remember, conservatories that are not thermally separated can have a detrimental impact on your EPC score.

A Proactive Approach to a Passive House

EPC - Passive House

A proactive approach to a Passive House

‘Passive House’ is a standard for a cost-effective, low-energy construction concept that produces buildings with remarkable energy efficiency qualities without compromising on comfort.  

With all of the necessary information published freely on-line, it is claimed that any competent architect can design a Passive House. The standard is also relevant to non-residential buildings such as schools and offices. While it is most simply achieved with a new-build, it can also be successfully applied during a major building renovation.

Passive House buildings combine the use of energy efficient materials, a very high level of floor, window, roof and wall insulation and an airtight design. They are designed to be ‘thermal bridge free’, meaning the insulation has no cold corners or weak spots, reducing any problems with condensation. Ventilation is nevertheless essential, and an unobtrusive system supplies constant fresh air to maintain high levels of internal air quality without creating draughts. It incorporates a highly efficient heat recovery unit that captures heat for re-use in the building.

The designers ensure that the building makes such efficient use of the sun, internal heat sources such as domestic appliances and heat recovery that a conventional heating system is unnecessary, even on the coldest days of winter. This is what defines a Passive House. During the summer, passive techniques such as strategic shading help to keep the building comfortably cool.

Tests and calculations on existing Passive House dwellings are producing some impressive data. Measurements carried out on more than a hundred Passive House properties in central Europe as part of the European Union’s CEPHEUS project showed average energy savings of approximately 90% by comparison with traditional building stock, and 75% savings against new-build equivalents.

As a result, Passive Houses are environmentally friendly by definition. While some additional energy may be required initially for their materials and construction, this is insignificant by comparison with the energy savings they enable throughout the life of the building.

Similarly, the necessary financial investment in high quality materials and design required by the Passive House standard will be offset by the greatly reduced cost of installing and running heating and cooling systems. Calculations for German Passive Houses suggest that initial construction costs are now only approximately 5% higher than those of a comparable traditionally built house. Payback periods of course depend on the size and construction cost of the building, but under most circumstances the reduced running costs are likely to offset the construction costs in two to three decades, even allowing for loan repayments.

The Building Research Establishment (BRE) is one of the certifying bodies for Passive Houses, and there are fewer than a hundred of its Passivhaus buildings in the UK. The ‘Sleepy Dorset’ blog (here) tells the story of one family’s self-build Passive House since 2016 and its successful achievement of Passivhaus status. It relates how the house performed in Dorset’s coldest winter weather for many years in March 2018, and how the family awoke each morning to a comfortable 18ºC without any heating, despite outside temperatures of -6ºC and thick snow.

The Biomass Boiler Alternative

Biomass Boiler

An Introduction to Biomass

Households that are not keen on modern renewable energy technologies might prefer a more traditional wood burner or biomass boiler. Man has been burning wood to provide heat since he first harnessed the power of fire in his cave, but a modern biomass boiler offers a more sophisticated solution to home heating.

Simple wood burning stoves provide heat and a focal point for the main room and can include a back boiler to run small-scale central heating and hot water systems. A biomass boiler works like a normal gas or oil boiler but they burn renewable biomass instead. New generation systems are easy to use and deliver greater than 75% energy efficiency using pellets or properly dried wood.

Systems are available for a range of fuels, including logs, wood chips, sawdust, grass-derived biomass pellets or even peat. The choice of fuel will be dictated by the availability and price of a reliable local supply and the type of storage available. The greatest savings are made when buying in bulk so to get the best deal a significant amount of storage space is required.

Pellets are much easier to transport and store than logs, and provide a more controllable heat. Pellet-fuelled biomass boilers are available with automatic fuel feeders and they can be programmed in much the same way as conventional gas boilers. Log-burning stoves and boilers involve considerably more work and are less controllable.

The installed cost of a wood burning stove will be around £2,500 to £7,500, depending on the model and the availability of a flue. The price of a full biomass boiler system is greater than that of a comparable gas boiler at between £10,000 and £20,000, depending on model, size and ease of installation.

After the initial outlay, the system should reduce energy bills over time, with some studies suggesting that a biomass boiler can save the average household up to £800 a year when compared with standard electric heating, or up to £210 a year compared with an old G-rated gas boiler. However, at typical 2018 prices, running a biomass boiler is likely to cost more than a modern condensing gas boiler.

To maintain efficiency, the flue will need to be cleaned annually at a cost of around £50. Another downside is the need to remove and dispose of ash. Some biomass boiler systems have automatic ash removal and compression systems that make the job easier.

Government support is available for the installation of a biomass boiler or biomass stoves with a back boiler through the Renewable Heat Incentive scheme. The income depends on the system and the amount of energy it produces but the payment for a biomass boiler in a four-bedroom, detached house may be nearly £2,000 per annum. To be eligible, the property must have a compliant EPC that is less than two years old.  There is a calculator and information on the BEIS website here.