Question 1

What is an energy performance certificate rating?

Accepted Answer

An Energy Performance Certificate (EPC) rating measures how energy efficient your property is, rated from A (most efficient) to G (least efficient). It shows current energy performance and recommendations for improvement.

Question 2

How do I check my EPC rating?

Accepted Answer

You can check your EPC rating on the UK government's EPC register at epcregister.com by entering your postcode. Alternatively, use our EPC checker tool which provides instant results.

Question 3

What is a good EPC rating?

Accepted Answer

An EPC rating of C or above is considered good. Properties with ratings D-G are eligible for ECO4 funding as they have room for energy efficiency improvements.

Question 4

How is an EPC rating calculated?

Accepted Answer

EPC ratings are calculated based on: property size, construction type, insulation levels, heating system efficiency, glazing type, and renewable energy systems. An accredited assessor evaluates these factors.

Question 5

How much does an energy performance certificate cost?

Accepted Answer

An EPC typically costs £60-£120 for residential properties. However, if you qualify for ECO4, we can arrange a free EPC assessment as part of your grant application.

Question 6

How to improve my EPC rating?

Accepted Answer

Improve your EPC rating by: installing a new efficient boiler, adding loft/cavity wall insulation, upgrading to double glazing, fitting smart heating controls, and installing renewable energy systems like solar panels.

Question 7

When is an EPC needed?

Accepted Answer

You need an EPC when selling or renting a property. For ECO4 grants, you need an EPC rating of D-G to qualify for funding.

Question 8

What does EPC rating E mean?

Accepted Answer

An EPC rating of E indicates below-average energy efficiency. Properties with E ratings often have older boilers, poor insulation, or single glazing. These properties qualify for ECO4 funding.

Question 9

What is EPC rating in UK?

Accepted Answer

In the UK, EPC ratings run from A (92+ points, most efficient) to G (1-20 points, least efficient). The average UK home has a D rating (55-68 points).

Question 10

What is energy efficiency rating?

Accepted Answer

Energy efficiency rating shows how efficiently your home uses energy for heating, hot water, and lighting. Higher ratings mean lower energy bills and reduced carbon emissions.

Question 11

What is a condensing boiler?

Accepted Answer

A condensing boiler is a high-efficiency boiler (90%+ efficient) that recovers heat from waste gases. It's the standard for all new boiler installations and significantly more efficient than older non-condensing models.

Question 12

What is the difference between combi and condensing boiler?

Accepted Answer

A condensing boiler refers to the technology (recovering waste heat), while a combi boiler describes the system type (providing heating and hot water without a tank). You can have a condensing combi boiler.

Question 13

What is a non-condensing boiler?

Accepted Answer

A non-condensing boiler is an older, less efficient type (60-80% efficient) that releases waste heat through the flue. These are no longer installed in the UK and should be replaced with condensing models.

Question 14

What is a back boiler?

Accepted Answer

A back boiler is an outdated heating system installed behind a fireplace. They're inefficient, expensive to run, and no longer manufactured. ECO4 offers grants to replace back boilers with modern efficient systems.

Question 15

Is a combi boiler a condensing boiler?

Accepted Answer

Most modern combi boilers are condensing boilers, but not all condensing boilers are combis. 'Condensing' refers to efficiency technology, while 'combi' refers to the system providing both heating and hot water.

Question 16

What is a system boiler?

Accepted Answer

A system boiler heats central heating and stores hot water in a cylinder. It's ideal for homes with high hot water demand or multiple bathrooms, unlike combis which heat water on demand.

Question 17

What is a megaflow system?

Accepted Answer

A Megaflo system is a brand of unvented hot water cylinder that provides mains pressure hot water. It's often paired with system boilers for properties requiring high water pressure.

Question 18

What is an unvented cylinder?

Accepted Answer

An unvented cylinder is a sealed hot water storage system connected directly to the mains water supply, providing high-pressure hot water to multiple outlets simultaneously.

Question 19

What is biomass heating?

Accepted Answer

Biomass heating uses wood pellets, chips, or logs to generate heat. It's a renewable heating option eligible for government grants through the Renewable Heat Incentive (RHI).

Question 20

What is a heat pump?

Accepted Answer

A heat pump is a renewable heating system that extracts heat from air or ground to warm your home. Air source heat pumps are eligible for £7,500 government grants through the Boiler Upgrade Scheme.

Question 21

What is cavity wall insulation?

Accepted Answer

Cavity wall insulation fills the gap between inner and outer walls with insulating material (foam, beads, or wool). It can reduce heat loss by 35% and save £160+ annually on energy bills.

Question 22

How much does cavity wall insulation cost?

Accepted Answer

Cavity wall insulation typically costs £500-£1,500 for an average 3-bed house. However, through ECO4, eligible households can get it completely free alongside boiler grants.

Question 23

What types of cavity wall insulation are there?

Accepted Answer

Main types include: mineral wool (rock wool), polystyrene beads, polyurethane foam, and expanded polystyrene (EPS). The best type depends on your wall cavity width and property condition.

Question 24

Does cavity wall insulation cause damp?

Accepted Answer

Properly installed cavity wall insulation doesn't cause damp. However, poor installation or unsuitable properties (exposed areas, existing damp issues) can have problems. Professional assessment is essential.

Question 25

What is loft insulation?

Accepted Answer

Loft insulation is material laid between and over floor joists in your attic to prevent heat loss through the roof. It can reduce heat loss by 25% and typically pays for itself within 2-3 years.

Question 26

How much loft insulation do I need?

Accepted Answer

UK building regulations recommend 270mm depth of loft insulation. Older homes often have just 100mm or less. ECO4 can provide free top-up insulation to bring it to recommended levels.

Question 27

What types of loft insulation are there?

Accepted Answer

Common types include: mineral wool blankets (glass or rock wool), loose-fill (cellulose or mineral wool), rigid boards (PIR or EPS), and spray foam. Blanket insulation is most common for DIY.

Question 28

What is external wall insulation?

Accepted Answer

External wall insulation (EWI) involves fixing insulation boards to outside walls and covering with render or cladding. It's ideal for solid wall properties and can save £455+ annually.

Question 29

What is the U-value of insulation?

Accepted Answer

U-value measures heat loss through building elements (walls, roof, windows). Lower U-values mean better insulation. Current building regulations require U-values of 0.18 W/m²K for walls and 0.16 for roofs.

Question 30

How long does loft insulation last?

Accepted Answer

Quality loft insulation lasts 40+ years with minimal degradation. Mineral wool and rigid boards are most durable, while loose-fill may settle over time and need topping up.

Question 31

How much is a new boiler?

Accepted Answer

A new combi boiler costs £2,000-£4,000 including installation, system boilers £2,500-£4,500, and regular boilers £2,000-£3,500. However, ECO4 provides free boilers for eligible households.

Question 32

How much is a combi boiler?

Accepted Answer

Combi boiler prices range from £1,500-£3,000 for the unit, plus £500-£1,000 installation. Popular brands: Worcester Bosch (£1,800-£2,500), Vaillant (£1,600-£2,400), Baxi (£1,200-£1,800).

Question 33

How much does a boiler service cost?

Accepted Answer

A standard boiler service costs £60-£120. Annual servicing is recommended to maintain efficiency, ensure safety, and keep warranties valid. Some providers offer service plans from £10-£15/month.

Question 34

How much does central heating installation cost?

Accepted Answer

Complete central heating installation costs £3,500-£6,000 for a 3-bed house, including boiler, radiators, pipework, and controls. ECO4's First Time Central Heating Grant covers this free for eligible homes.

Question 35

How much is an air source heat pump?

Accepted Answer

Air source heat pumps cost £7,000-£13,000 installed. However, the government's Boiler Upgrade Scheme provides £7,500 grants, reducing costs to under £5,000 for most installations.

Question 36

How much do heat pumps cost to run?

Accepted Answer

Heat pumps cost 15-25p per kWh to run (electricity rate). While higher than gas (7-10p/kWh), heat pumps are 300%+ efficient, so running costs are often similar or lower than gas boilers.

Question 37

Are oil-filled radiators cheap to run?

Accepted Answer

Oil-filled radiators cost 30-50p per hour to run at 1.5kW. They're more efficient than fan heaters but expensive for whole-home heating compared to central heating systems.

Question 38

How much does it cost to move a boiler?

Accepted Answer

Relocating a boiler costs £500-£1,500 depending on distance and complexity. Costs include disconnection, new pipework, gas connections, flue installation, and recommissioning.

Question 39

How much to replace a boiler with combi?

Accepted Answer

Converting to a combi boiler costs £2,500-£4,000, including removing old system, installing new boiler, capping pipework, and removing tanks. ECO4 covers this free for eligible households.

Question 40

How much does cavity wall insulation cost per m²?

Accepted Answer

Cavity wall insulation costs £15-£25 per m². For a typical 3-bed semi (85m² wall area), total cost is £1,275-£2,125. ECO4 provides this free for qualifying homes.

Question 41

Which are the best boiler brands in UK?

Accepted Answer

Top UK boiler brands include: Worcester Bosch (excellent reliability, 10-year warranties), Vaillant (German engineering, innovative features), Baxi (value for money), Ideal (good mid-range option), and Viessmann (premium German brand).

Question 42

What are Worcester Bosch boilers like?

Accepted Answer

Worcester Bosch boilers are the UK's most popular brand, known for reliability and efficiency. They offer 10-year warranties, A-rated efficiency, and excellent after-sales support. Prices range from £1,800-£2,500.

Question 43

Are Vaillant boilers good?

Accepted Answer

Vaillant boilers are premium German-engineered units with excellent build quality and efficiency. They're known for quiet operation, innovative controls, and 7-10 year warranties. Slightly more expensive but highly reliable.

Question 44

Are Baxi boilers reliable?

Accepted Answer

Baxi boilers offer good value for money with decent reliability. They're more affordable than Worcester or Vaillant but may have slightly lower build quality. Good choice for budget-conscious homeowners. 7-year warranties available.

Question 45

What are Ideal boilers like?

Accepted Answer

Ideal boilers are solid mid-range options with good efficiency and reliability. They offer competitive pricing (£1,400-£2,000) and up to 12-year warranties. Popular models include Logic+ and Vogue ranges.

Question 46

Are Viessmann boilers good?

Accepted Answer

Viessmann boilers are premium German units with exceptional build quality and efficiency. They're slightly more expensive but offer advanced features, very quiet operation, and excellent longevity. 10-year warranties standard.

Question 47

What are Alpha boilers like?

Accepted Answer

Alpha boilers are budget-friendly units manufactured in the UK. They offer decent reliability for the price but may not last as long as premium brands. Good for landlords or temporary solutions. 5-7 year warranties.

Question 48

Are Biasi boilers any good?

Accepted Answer

Biasi boilers are economy options made in Italy. They're significantly cheaper than major brands but have mixed reliability reviews. Best suited for budget installations with shorter expected lifespan.

Question 49

What is the best combi boiler?

Accepted Answer

Best combi boilers include: Worcester Bosch Greenstar 4000 (best overall), Vaillant ecoTEC Plus (best features), Ideal Logic Max (best value), and Viessmann Vitodens 200-W (best premium option).

Question 50

What is the best boiler for a 3-bedroom house?

Accepted Answer

For a 3-bed house with 1 bathroom, a 30-35kW combi boiler is ideal. Recommended models: Worcester Bosch Greenstar 30CDi, Vaillant ecoTEC Plus 832, or Ideal Logic Max 30kW.

Question 51

What are the different types of heating systems?

Accepted Answer

Main types include: combi boilers (instant hot water), system boilers (with cylinder), regular boilers (with tanks), heat pumps (renewable), electric heaters, and warm air systems (older properties).

Question 52

How does a central heating system work?

Accepted Answer

Gas boiler heats water, pump circulates hot water through pipes to radiators, heat transfers to rooms, cooled water returns to boiler, thermostat controls temperature, and timer manages operating schedules.

Question 53

What is a thermostatic radiator valve (TRV)?

Accepted Answer

A TRV is a self-regulating valve that controls individual radiator temperature. It automatically adjusts water flow based on room temperature, allowing different temperatures in different rooms and saving energy.

Question 54

How do thermostatic radiator valves work?

Accepted Answer

TRVs contain temperature-sensitive wax or liquid. As room temperature rises, the element expands and closes the valve, reducing water flow. As it cools, the valve opens again to maintain set temperature.

Question 55

What temperature should radiators be set at?

Accepted Answer

Living areas: 18-21°C (TRV setting 3-4), bedrooms: 16-18°C (TRV setting 2-3), bathrooms: 22-24°C (TRV setting 4-5). Central heating flow temperature should be 60-70°C for efficiency.

Question 56

How to balance radiators?

Accepted Answer

1) Turn all radiators fully on, 2) Identify flow and return pipes, 3) Turn off all lockshield valves, 4) Open lockshields on radiator furthest from boiler, 5) Gradually open lockshields on other radiators, 6) Aim for 12°C temperature difference between flow and return.

Question 57

Why is my radiator cold at the bottom?

Accepted Answer

Radiator cold at bottom usually indicates sludge buildup. Solution: power flush the system, add central heating inhibitor, and consider magnetic filter installation. This is common in older systems.

Question 58

What are smart heating controls?

Accepted Answer

Smart heating controls (like Nest, Hive, or Tado) allow remote control via smartphone, learn your routine, provide room-by-room control, show energy usage, and can save 10-20% on heating bills.

Question 59

How does wireless thermostat work?

Accepted Answer

Wireless thermostats communicate with boiler via radio signals. No wiring needed between thermostat and boiler. Battery-powered thermostat can be placed anywhere for optimal temperature sensing.

Question 60

What is a central heating timer?

Accepted Answer

A central heating timer controls when your heating switches on and off automatically. Modern programmers allow multiple on/off periods per day and different schedules for weekdays and weekends.

Question 61

What is the ECO4 scheme?

Accepted Answer

ECO4 (Energy Company Obligation 4) is a government scheme running until 2026 that provides free or subsidized home energy improvements including boilers, insulation, and heating controls for eligible low-income households.

Question 62

Who qualifies for ECO4 scheme?

Accepted Answer

You qualify if you receive qualifying benefits (Universal Credit, Pension Credit, etc.), have household income under £31,000, own your home or are a tenant with permission, and have an EPC rating of D-G.

Question 63

What grants are available through ECO4?

Accepted Answer

ECO4 provides: free boiler replacements, first-time central heating, cavity/loft/external wall insulation, smart heating controls, air source heat pumps, and solar panels. All fully funded for eligible households.

Question 64

Can I get a free boiler if I'm on Universal Credit?

Accepted Answer

Yes, Universal Credit recipients automatically qualify for ECO4 free boiler grants if they own their home or have landlord permission and their property has an EPC rating of D-G.

Complete Boiler & Energy Efficiency FAQ

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ECO4 Scheme Guide

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Complete Boiler & Energy Efficiency FAQ

What is an energy performance certificate rating?EPC Ratings & Energy Efficiency

How do I check my EPC rating?EPC Ratings & Energy Efficiency

What is a good EPC rating?EPC Ratings & Energy Efficiency

How is an EPC rating calculated?EPC Ratings & Energy Efficiency

How much does an energy performance certificate cost?EPC Ratings & Energy Efficiency

How to improve my EPC rating?EPC Ratings & Energy Efficiency

When is an EPC needed?EPC Ratings & Energy Efficiency

What does EPC rating E mean?EPC Ratings & Energy Efficiency

What is EPC rating in UK?EPC Ratings & Energy Efficiency

What is energy efficiency rating?EPC Ratings & Energy Efficiency

What is a condensing boiler?Boiler Types & Technology

What is the difference between combi and condensing boiler?Boiler Types & Technology

What is a non-condensing boiler?Boiler Types & Technology

What is a back boiler?Boiler Types & Technology

Is a combi boiler a condensing boiler?Boiler Types & Technology

What is a system boiler?Boiler Types & Technology

What is a megaflow system?Boiler Types & Technology

What is an unvented cylinder?Boiler Types & Technology

What is biomass heating?Boiler Types & Technology

What is a heat pump?Boiler Types & Technology

What is cavity wall insulation?Insulation & Home Improvements

How much does cavity wall insulation cost?Insulation & Home Improvements

What types of cavity wall insulation are there?Insulation & Home Improvements

Does cavity wall insulation cause damp?Insulation & Home Improvements

What is loft insulation?Insulation & Home Improvements

How much loft insulation do I need?Insulation & Home Improvements

What types of loft insulation are there?Insulation & Home Improvements

What is external wall insulation?Insulation & Home Improvements

What is the U-value of insulation?Insulation & Home Improvements

How long does loft insulation last?Insulation & Home Improvements

How much is a new boiler?Costs & Savings

How much is a combi boiler?Costs & Savings

How much does a boiler service cost?Costs & Savings

How much does central heating installation cost?Costs & Savings

How much is an air source heat pump?Costs & Savings

How much do heat pumps cost to run?Costs & Savings

Are oil-filled radiators cheap to run?Costs & Savings

How much does it cost to move a boiler?Costs & Savings

How much to replace a boiler with combi?Costs & Savings

How much does cavity wall insulation cost per m²?Costs & Savings

Which are the best boiler brands in UK?Boiler Brands & Models

What are Worcester Bosch boilers like?Boiler Brands & Models

Are Vaillant boilers good?Boiler Brands & Models

Are Baxi boilers reliable?Boiler Brands & Models

What are Ideal boilers like?Boiler Brands & Models

Are Viessmann boilers good?Boiler Brands & Models

What are Alpha boilers like?Boiler Brands & Models

Are Biasi boilers any good?Boiler Brands & Models

What is the best combi boiler?Boiler Brands & Models

What is the best boiler for a 3-bedroom house?Boiler Brands & Models

What are the different types of heating systems?Heating Systems & Controls

How does a central heating system work?Heating Systems & Controls

What is a thermostatic radiator valve (TRV)?Heating Systems & Controls

How do thermostatic radiator valves work?Heating Systems & Controls

What temperature should radiators be set at?Heating Systems & Controls

How to balance radiators?Heating Systems & Controls

Why is my radiator cold at the bottom?Heating Systems & Controls

What are smart heating controls?Heating Systems & Controls

How does wireless thermostat work?Heating Systems & Controls

What is a central heating timer?Heating Systems & Controls

What is the ECO4 scheme?ECO4 Scheme & Grants

Who qualifies for ECO4 scheme?ECO4 Scheme & Grants

What grants are available through ECO4?ECO4 Scheme & Grants

Can I get a free boiler if I'm on Universal Credit?ECO4 Scheme & Grants

Can I get a free boiler if I'm on Pension Credit?ECO4 Scheme & Grants

What is LA Flex scheme?ECO4 Scheme & Grants

Can tenants get free boilers through ECO4?ECO4 Scheme & Grants

Are there grants for landlords?ECO4 Scheme & Grants

What is the boiler scrappage scheme?ECO4 Scheme & Grants

Can I get help with boiler replacement?ECO4 Scheme & Grants

Are heat pumps worth it?Heat Pumps & Renewable Heating

How do air source heat pumps work?Heat Pumps & Renewable Heating

What is the difference between air to air and air to water heat pumps?Heat Pumps & Renewable Heating

Do heat pumps work with radiators?Heat Pumps & Renewable Heating

How much electricity does a heat pump use?Heat Pumps & Renewable Heating

What size heat pump do I need?Heat Pumps & Renewable Heating

How much does heat pump installation cost?Heat Pumps & Renewable Heating

Are heat pumps noisy?Heat Pumps & Renewable Heating

Can I get a grant for heat pump?Heat Pumps & Renewable Heating