PHPP — the Passive House Planning Package — explained for normal people: what it is, how it differs from SAP, how to read one, where to learn it, and when to bring in help.
Skip to: get a PHPP modelThe Passive House Planning Package is an energy model in spreadsheet form, developed and maintained by the Passive House Institute in Darmstadt. The current version, PHPP 10, runs in Excel. That sounds unglamorous — it is — and it's also the most trusted residential energy-modelling tool in Europe, because its predictions have been checked against measured buildings for three decades and they hold.
You feed it your building: wall build-ups and their U-values, window sizes and orientations, thermal bridges, airtightness, ventilation strategy, climate data for your location. It gives you back the numbers that matter: annual heating demand in kWh/m², peak heating load, summer overheating frequency, primary energy use.
The point is timing. PHPP answers "will this design work?" before construction — when changing the answer costs a revised drawing, not a rebuilt wall.
SAP — the Standard Assessment Procedure — is the UK's compliance methodology. It produces EPC ratings and demonstrates Building Regulations compliance using standardised occupancy and climate assumptions. It has to be standardised, because its job is comparing dwellings fairly, not predicting your bills.
PHPP's job is the opposite: predict this one building, accurately. Real local climate data, real build-ups, thermal bridges accounted individually, summer behaviour modelled rather than assumed. The practical consequence: a home can achieve a decent SAP score and still be uncomfortable and expensive to run, because SAP was never designed to catch that. PHPP is.
The two aren't competitors on a project — SAP (and from 2027, the Home Energy Model) handles the paperwork; PHPP drives the decisions. Architects' deeper dive: PHPP modelling for UK architects.
You need an EPC, Building Regs sign-off, or MEES compliance evidence. It's the legal language of UK housing.
You're deciding what to build: retrofit measures, extension fabric, glazing, ventilation. Anywhere the answer costs real money if it's wrong.
You're doing a deep retrofit or new build with certification or funding attached — PAS 2035 and EnerPHit routes typically want both worlds covered.
APMBuild doesn't run PHPP courses, doesn't issue certificates and won't pretend otherwise. If you want to learn the tool properly, the path is well marked: buy the licence (a one-off purchase from the Passive House Institute or, in the UK, the AECB — the extensive handbook is included), then take a course from a PHI-accredited training provider if you want structured teaching. The certified routes run up to Passive House Designer and Consultant level.
If you're a builder or self-builder who needs the site skills that make a PHPP model come true — airtightness sequencing, thermal-bridge detailing, window installation — that's a different kind of learning, and it's the one we do offer: on-site mentoring, builder-to-builder on your project. Knowledge transfer, not classroom training.
For a gentler start than the handbook, our free PHPP Explained guide (PDF) walks through a real report page by page — and the EnerPHit retrofit guide shows where the model fits in a whole project.
Most homeowners don't need to learn PHPP — they need one good model of their own house.
A PHPP pre-assessment tells you where your home loses heat and what to fix first — before you spend on the wrong measures.
Book a Pre-AssessmentThe questions people actually search for — software, cost, SAP, and when to get help.
PHPP — the Passive House Planning Package — is an energy-modelling tool developed by the Passive House Institute. It is a very large, very carefully validated spreadsheet: you enter your building's geometry, insulation, windows, airtightness and ventilation, and it calculates how much heating the building will need, whether it will overheat in summer, and whether it meets Passive House or EnerPHit targets. Its predictions track measured performance closely, which is why it's used for design rather than just compliance.
SAP is the UK government's compliance methodology — it exists to produce EPC ratings and check Building Regulations, using standardised assumptions. PHPP is a design tool — it exists to predict how a specific building will really perform, and it is accurate enough to design to. A house can score well in SAP and still be cold and expensive to run; a house designed in PHPP behaves the way the model said it would. Many projects sensibly use both: SAP for the paperwork, PHPP for the decisions.
The software itself is a one-off licence from the Passive House Institute or its national partners (in the UK, the AECB) — currently sold as a single-user licence with the handbook included. Having a model built for you is a separate cost: APMBuild's PHPP pre-assessment starts at £750 + VAT, with full certified models from around £1,800 + VAT via our PHI-accredited partner.
Yes, if you're comfortable with spreadsheets and building physics basics — the licence includes a thorough handbook, and PHI-accredited course providers run certified training up to Passive House Designer and Consultant level. APMBuild does not run PHPP courses or issue qualifications; for hands-on site skills we offer builder-to-builder on-site mentoring, which is knowledge transfer on your project, not classroom training.
For a formal Passive House or EnerPHit certification, yes — the certifier requires a properly built PHPP model, and APMBuild delivers those through a PHI-accredited partner. For an extension, renovation or retrofit where you want confidence rather than a certificate, a PHPP pre-assessment is usually the right level: it models your actual building and tells you where the heat goes before you spend money on the wrong measures.