Introduction Video (2 mins)
Build PHPP video

1 Select Climate – using a standard map or one with county boundaries
2 Site – enter orientation and ventilation exposure
3 U-values – 30 standard U-value construction build-ups you can use and edit, including 6 scenarios for each, wall tie calculations and option to write variants. Also includes timber fractions from BRE BR443. Also has variants option.
4 k-values – choose build ups of k-values from a library, will open BBAs in Chrome or Internet Explorer to allow you to download. Includes values from PHPP manual, BRE BR443, EN 12524:2000, some SPAB in situ U-value tests for granite and limestone walls. You can add or modify values and create your own list groups.
5 Window Tool – enters most of the info for a window on both the window and the shading tabs including, ‘1’s and ‘0’s, name, d reveal, o reveal, d over and o over.
6 Daylight Factor – writes a daylight factor spreadsheet by Mark Siddall of (LEAP)
7 Energy of Variants – adds a “Graphs” tab and graphs variants broken down by walls, roof, etc
8 Embodied CO2 – calculates the Embodied CO2 for any building based through a series of dialogues
9 Simple – adds retrofit costs of just the current PHPP
10 Variants – find retrofit costs for a series of variants all at once
11 Step By Step – retrofit in incremental stages, using variants
12 U-values – view/edit the U-values library
13 k-values – view/edit k-value library
14 Costs – view/edit retrofit costs library
15 TBs – view the Thermal Bridges library
16 Embodied CO2 – view/edit embodied CO2 library


The basic new build version (£45) has tools 1 to 5, 7 and the associated libraries 12 and 13.
You can download and watch training videos from our download page. Extra modules are easily added:

  • Indicative costs for retrofits: Simple, Variants and Step by Step (£30)
  • International version (no extra charge, user to provide local costs)
  • NEW! Daylight factor (£75)
  • NEW! Embodied CO2 (£20)
  • NEW! Google Docs shared libraries (opens in new tab), free



Window Tool (Button 5)

The window tool helps you add windows by entering much of the data for you. On the windows tab it enters the dimensions, ‘1’s and ‘0’s and name. On the Shading tab it enters the d reveal, o reveal, d over and o over. It uses frame dimensions from the components tab to enter the d reveal as a formula so it will update if you change the window or frame dimensions.

Climate (Button 1)

Helps you enter climate. Choose your climate from either the standard map or one with county boundaries.

U-Values (Button 3)

Choose U-value build-ups from a library of up to 30. Copies to and from the library, can also set up 6 variants.

k vaules (Button 4)

Choose build ups of k-values from a library, with links to BBAs to download. The categories on the left are used to filter the list you see, the top 3 categories are fixed, the next 3 have useful common situations which you can customise yourself and the last 3 are entirely blank allowing you to create your own lists.

Daylight Factor (Button 6)

This is a spreadsheet by Mark Siddall of LEAP. It helps you plan window sizes which give enough daylight without over-provision, even good windows have 5x the heat loss of a good wall. It writes a separate spreadsheet for calculating daylight factor and fills out the information that is known from the PHPP (the windows and frames). There then remains a small amount of further info to enter to obtain daylight factors for each room.

Embodied CO2 and Retrofit Costing

Button 8 gives Embodied CO2, the CO2 used to manufacture the materials used, suitable for new build and retrofit and also works for variants as well.
Buttons 9-11 give AECB REALcosting software in 3 buttons that work directly in your PHPP: (9) without variants, (10) using Variants and (11) where each variants is a step of a retrofit. For each a costs tab is added to your PHPP and is custom written in front of you.

Button 15

Part of the Thermal Bridge Library is shown below, showing the construction build up for each calculation. Psi values are given for several different thicknesses of each configuration.