- Building Control has asked for a water calculation — what now?
Plain-English help when Building Control asks for a water efficiency calculation.
- 125 litres per person per day, explained
How the 125 l/p/d water calculation works and how to pass it.
- The 110 litres per person per day planning condition
The tighter optional water standard many councils require, and how to meet it.
- What is Thermal Bridging?
Why junctions leak heat, what Ψ-values are, and how calculated values improve your SAP result.
- Building Regulations Part L Explained
What Part L requires for new dwellings, extensions and conversions — and when SAP is needed.
- What is PHPP (and when do you actually need it)?
What PHPP is, which planning policies require it for an energy statement, and how it differs from Passivhaus certification.
- SAP 10: What's New in Part L 2021?
The SAP 10 changes that matter: tighter notional dwelling, PV assumption, new carbon factors, thermal bridging.
- What is the Future Homes Standard?
The 2027 standard for new homes in full: mandatory solar PV, tighter U-values, heat pumps, SAP 10.3 vs HEM, costs and transitional dates.
- What is DER/TER?
The dwelling vs target CO₂ emission rates at the heart of every SAP pass or fail.
- What is Fabric Energy Efficiency (DFEE/TFEE)?
The kWh/m²/yr fabric target that ensures the building itself — not just its renewables — performs.
- What is a U-value?
The W/m²K measure of element heat loss, how it's calculated, and the Part L limits that apply.
- What are Accredited Construction Details (ACDs)?
The retired junction-detail scheme, and what to use instead under SAP 10.
- What is the Energy Hierarchy?
The reduce-first principle behind Part L and most planning energy policies.
- Why is Fuel Choice Important in SAP?
How gas, electric, heat pump, LPG and oil choices change a SAP result.
- What is a Predicted Energy Assessment (PEA)?
The off-plan predecessor to the EPC, produced from design-stage SAP.
- Renewable Technologies: An Overview
The main low-carbon technologies compared, with their SAP impact.
- Solar PV (Photovoltaic Panels)
Electricity-generating panels: the workhorse of SAP passes and planning conditions.
- Heat Pumps: An Introduction
How heat pumps work and why they're the new-build heating default.
- Air Source Heat Pumps (ASHP)
The go-to low-carbon heating for new builds — how ASHPs work and score in SAP.
- Ground Source Heat Pumps (GSHP)
The high-efficiency, high-cost heat pump: loops, boreholes and SAP performance.
- Solar Hot Water (Solar Thermal)
Solar thermal for hot water — and when PV + diverter beats it.
- MVHR (Mechanical Ventilation with Heat Recovery)
Whole-house ventilation that recovers heat — ideal for airtight new builds.
- WWHR (Waste Water Heat Recovery)
Shower drain heat recovery: small cost, easy SAP points, assumed in SAP 10's target.
- FGHR (Flue Gas Heat Recovery)
Recovering flue heat from gas boilers for extra hot-water efficiency.
- What is Weather Compensation?
Outdoor-sensing heating control that lowers flow temperatures and earns SAP credit.
Guides (jargon, decoded)
Plain-English explanations of energy assessment jargon, Building Regs and low-carbon tech — written by working assessors who use this stuff daily, not marketers reaching for a thesaurus.
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