What is passivhaus
Passivhaus is a rigorous standard for energy-efficient buildings focused on comfort, airtightness, and minimal heating needs.
5 minGlossary
Plain-English definitions of the terms in quotes, surveys and grant forms - BREEAM to U-values.
21 guides
Insulation R value defined: units, meaning, and typical UK material levelsR value measures how well insulation resists heat flow. Higher numbers mean better performance, and the metric unit is m²·K/W.9 min read
Solar thermal: how sunlight heats water and powers home heating systemsSolar thermal uses sunlight to heat a fluid directly for a home’s hot water and heating needs; performance depends on collector type, system design and location.9 min read
Solar PV: what it stands for, how panels and systems work togetherSolar PV converts sunlight into electricity via panels and a home system, helping UK homes reduce energy bills and improve EPC ratings.7 min read
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LEED certification for buildings: what it means and how levels differ
Look at what LEED certification is, the impact of LEED Gold, and how it differs from other green building standards like BREEAM and WELL.
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Embodied carbon in building materials: what counts and typical UK levels
Embodied carbon measures greenhouse gas emissions from producing building materials, covering extraction through installation stages with examples for UK construction.
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What is BREEAM and what do Excellent and Very Good ratings mean
Understand what BREEAM is and how its sustainability ratings like 'Excellent' and 'Very Good' impact UK construction projects and building performance.
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Biomass heating: what it is, how it works, and common system types
Find out how biomass heating systems work, their common types, and how they compare to other green heating methods in UK homes.
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Anaerobic digestion process: how it breaks down waste without oxygen
Anaerobic digestion breaks down organic waste without oxygen, producing biogas and digestate useful for energy and fertiliser.
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Energy Performance Certificate: what it shows, how to check UK validity
Learn what an Energy Performance Certificate is and how to verify its validity online in the UK, including key differences in Scotland.
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Air source heat pump: how it works and what it heats in UK homes
An air source heat pump moves heat from outside air to heat your home or water, cutting energy use even in cold UK weather.
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What is a U-value in construction and how it compares to R- and K-values
A U-value measures heat loss through building elements in W/m²K, crucial for assessing insulation performance and improving EPC ratings.
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What is sap rating
SAP rating is a numerical measure of a home's energy efficiency used in the UK, different from but related to EPC ratings.
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Ground source heat pump: what it is and how it uses the earth’s heat
A ground source heat pump uses stable earth temperatures to efficiently heat your home, offering a renewable alternative to traditional heating systems.
6 min
What is a green home
Find out what makes a green home in the UK, including key features, energy performance, and eligibility for government grants and schemes.
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Modular vs prefabricated housing: clear definitions and key differences
Clear definitions and differences between modular and prefabricated housing plus whether modular homes are always prefabricated.
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Home wind turbines uk worth it
Weigh UK home wind turbines' costs and savings to judge if they pay off compared with solar alternatives.
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Micro hydro power for homes how to choose the right system
Learn how to select the right micro hydro power system for your home based on your water source’s flow and head measurements.
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Green energy tariff: what it must supply and how to verify it
Learn the official criteria defining a green energy tariff and how to check if your energy supplier meets them.
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Fuel cell boiler: how it produces heat and saves energy at home
A fuel cell boiler uses hydrogen in an electrochemical process to produce heat and (often) electricity; it can be very efficient when paired with low-carbon hydrogen, though UK hydrogen
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Code for Sustainable Homes: levels, technical guide, and withdrawal status
The Code for Sustainable Homes was a UK standard ranking homes 1 to 6 for sustainability but was withdrawn in 2015 and replaced by updated building regs.
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