News

It's been a while since the last general update in September. A lot of work has gone into the new floor u-value calculator, which is now live, and we've fixed a laundry list of bugs and made various updates and tweaks to functionality too.

Behind the scenes we're still working on some bigger changes that aren't yet ready for public consumption as we're testing them internally: an new address search page and a rewrite of part of the fabric page. We'll write more on these when we release them generally.

Miscellaneous fixes and tweaks

• Fix bug where new heating systems would always have the category of 'Warm air systems'
• Format output numbers better - in new code, we now use commas as a thousands separator (visible on e.g. the current energy page)
• Improve performance of library item selection - previously the frontend was fetching all libraries every time an library item needed to be selected, which was slow. Now we fetch once on page load
• Fix image rotation on report output
• Fix 'add floor' button on dwelling data page which sometimes malfunctioned
• Fix 'delete appliance' button on appliance page which sometimes malfunctioned
• Try to make sure the bulk measure application dialogue box pop-up fits on the screen, and make it scrollable
• Fix various typos and remove mentions of MHEP
• Update fuel costs
• When loading an assessment, show the first page on the sidebar (household questionaire)
• Show an error on the export screen if you click the button to import an assessment file but you haven't selected a file
• Add 'for review' status for assessments - this is intended to make it easier to see what assessments are in progress and which are waiting for QA
• Assessments shared with multiple users no longer cause a server error
• Remove faulty handling of space cooling demand, which sometimes caused the fuel requirements pages of assessments to break. It was only triggered in about 1 in every 300 assessments, and the implementation was incompete and not compliant with SAP
• Fix bug where current energy page was showing carbon emissions per area figure for total carbon emissions
• Current energy page now shows total energy use and has end-use energy intensity on the comparison charts
• Be smarter about saving data to the server - avoid trying to send multiple updates to the server at once because this caused a race condition which meant data could sometimes be lost

Report changes

• Fix the bills data bar of the fuel costs graph, which was calculated wrongly if there was generation
• Display heating system on/off duration as hours and minutes - so e.g. write "6 hours 20 minutes" rather than "6.3333333 hours"
• Fix the output of user-provided text in the report, which output "it's" as "it'" due to HTML encoding issues

Refactoring work

And we have continued rewriting parts of HRP to make it more robust. In particular, the generation & current energy sections of the model have been rewritten and so has page navigation & management, which is more robust than before.

We've implemented a new floor U-value calculator on the fabric page over the last few months and we've finally turned it on for all our users.

As you may know, calculating the thermal transmittance of a floor is complex, as it depends on the floor's construction and exposed perimeter. The previous calculator left a lot to be desired in terms of managing this complexity, and asked for information such as soil type which is rarely available. As a result, we've rewritten it from scratch and simplified it.

The old calculator was a separate tool and was not integrated into the fabric elements page. The new calculator is a first-class section of the fabric model. You enter data for it in the same way as you do for other elements:

This means that all the data you enter is saved as part of the floor. This is another difference with the old calculator, which didn't save calculator inputs.

The input of floor layer materials is also more intuitive and robust. And unlike the previous verison, errors or warnings are shown to the user; this could be due to missing data or if there are problems using the data entered.

As ever, we welcome feedback on this new feature, so please let us know if you have queries or suggestions for improvement.

This month we have some changes to the image gallery and current energy pages, plus several bug fixes.

New image gallery

We've implemented a new and less annoying image upload feature:

• You can now drag and drop files to upload onto the page
• There's a list of images to upload, which have individual uploading statuses, so you can see how far along the upload process is - and you know which files failed to upload if there's a problem
• We'll only upload two images concurrently - previously if you had, say, 25 images, the app would try to upload them all at once and this could cause upload failures.

New current energy page

Again, this looks pretty similar to the old page - but under the hood it's totally different code. We've provided side-by-side comparisons on the bar charts between baseline and current use, and improved the alignment and visual appearance of the table, with the numbers lining up nicely in columns.

We do have plans to align the reporting in the app with the reporting in the report – but this is something we'll be looking at closer in 2023.

"Carbon Co-op"-style appliances bug fix

We discovered a set of related bugs in the Carbon Co-op appliances calculations that together led to space heating demand (SHD) being higher than it should be. In the majority of affected assessments, the overestimate was between 1% and 5%, though in some it was more significant. (In many assessments this behaviour was not triggered at all.)

In keeping with our backwards compatibility policy for building model changes, projects started before this bug was fixed will retain their old calculations, but new projects will use the fixed version.

Smaller bug fixes

• Per person energy use and CO₂ emissions were swapped on the 'compare scenarios' page
• The household questionnaire page's layout had been messed up - it's now readable again.
• Applying bulk measures to window elements that don't have the 'subtract from' field set is now possible.

Coming soon

We'll have the new floor u value calculator ready hopefully in October - we'll post about that when it goes live.

We've added a couple of bigger features over the last months, alongside a larger set of smaller fixes and improvements.

New report

HRP has now has a new report. This is a big update and addresses various issues with the old report: * the report template has been reworked to put the most important sections first, as well as reduced in size * the graphs in the report are of a higher quality and show more useful information * PDF generation is built in instead of relying on the web browser to produce a report, which often produced bad results

A sample report is available, showing the new report format.

Solar hot water estimator

Solar hot water data entry in the tool previously required information that is not typically available. We've added an estimator feature, following SAP, that does not require a test certificate.

Other changes

Performance

• We improved the load time of the list of assessments page. For some users it taking a noticeable amount of time to show the assessment list - now it's near-instant on a good connection.
• Only load libraries once when the assessment is loaded, rather than refetching them every time a library item is required, removing a delay when using the library selector

Usability

• New library selector for wall elements. This is the first stage of a usability refresh of the fabric page, and other library selectors (for floors, windows, etc.) will start to follow the same design as the new wall selector.
• New heating page layout. It's now less ugly and helps avoid the need to scroll far to the right.
• Assessment list entries are sorted by date last modified within the status categories (in progress, complete etc)
• If an assessment is marked as 'complete' no further changes can be made - but the only indication of this in the interface were confusing error messages. Now there is an alert when opening an assessment if it can't be saved to clarify the situation.
• The side menu no longer disappears if you reduce the size of the browser window

Bugs fixed

• Intermittent failure of "Add floor" button on 'dwelling data'
• Images in the image gallery are not rotated correctly

We've got quite a lot to write about since our last update in January.

New fuel costs

We've updated the fuel costs in HRP to the ones published by BRE for rdSAP in January 2022. These are used for new assessments only. We don't retrospectively update the fuel costs in work-in-progress or completed assessments for data integrity reasons - you want to know the basis upon which calculations were made in the past.

We expect another update from BRE soon and we'll implement that when it comes out.

Cost rounding

In the measures list in the report or CSV 'scope of works' outputs, we are now rounding the costs on elements. Previously these were providing a misleading level of accuracy. If an individual measure's cost is under £500, we round up to the next £5; if it's under £5000, we round up to the next £50; and otherwise (when the cost is above £5000) we round up to the next £500 increment.

Reworked solar hot water view

Our newest software engineer Joe has been working on a new solar hot water calculation page. We've been using this page to experiment with the kind of improvements we want to make to the rest of the app over time. In particular, we now disable inputs if the scenario is locked, validate that the numbers entered in this page are in fact numbers, and the 'enable/disable SHW' checkbox has moved onto the page itself rather than sitting on the sidebar.

In the near future we'll be adding a feature to this page to allow users to use the options listed in SAP rather than needing the values from a test certificate, or guessing them.

Smaller changes

• We removed the 'detailed list' from the lighting, appliances and cooking page. This was unused and we didn't recommend people used it – it gave a spurious level of certainty to the calculations.
• We made the code that saves assessments to the server more resilient to errors.
• Fix report output re aesthetics booleans
• Generation now has a fuel cost (again, in new assessments only). This means that in the 'fuel costs' section the overall cost gets calculated correctly – previously generation has no way of impacting on running costs. This saving will also be shown on the new report (see below).

Reliability

We introduced a bug in early February which caused some building fabric elements to have their areas calculated wrong. We fixed this and informed everyone whose assessments it affected. Every time we find a bug like this we try to work out how we can catch it before it affects anyone through automated methods, and this case is no exception. We have since added an approach to automated testing that would help prevent this bug making it to the live service in future.

Another bug meant that briefly a user could not start a new assessment. We've fixed this one but we've not yet written the tests that would prevent it. So far with HRP, we've been focusing on testing the HRP server software and the model calculations, but it's clear we do need some automated testing for the user interface too. That's one of the top things on our list for the next month.

New report template

We've also been working hard on a new report template for our users over the last couple of months and it's almost ready to launch. We'll be in touch with tech leads at our partner organisations before this goes live to finalise the text for each organisation's report.

Future plans

Our plan with HRP in 2022 is to work on foundational improvements: improving reliability and reworking the application internally so that we can make changes faster in future. We have quite a lot of behind-the-scenes plans for Q2 2022 but in terms of user-visible stuff, we hope to bring online:

• the solar hot water estimator (mentioned above)
• a rework of the 'household questionnaire' aspect of the tool, designed to be more thorough, so we can e.g. make better recommendations about heat pumps
• a new floor U-value calculator, as we're aware this is something that users can struggle with a bit at the moment.

Bugs fixed

• Fix number of storeys override not persisting on page reload (#742)
• Commentary page fails to save if household questionnaire page wasn't viewed at least once (#756)
• Water storage measures were never output to measures tables or SoW (#735)
• Display users' names in assessment list rather than email address or just lowercase first name
• Link to better altitude finder on the context page
• Improve Scope of Works CSV output
• Clarify text on lighting page for lighting outlets & low energy lighting outlets
• Add reference to SAP to define 'sides sheltered' on ventilation page

Reliability

We've introduced automated testing into our workflow to make sure that when we make changes things don't break. We did have a downtime incident in November where the app was inaccessible for \~50 minutes due to faulty configuration, and we've set up a test to make sure that we can't deploy a totally nonfunctional app in the future.

We also now have tests to make sure that old assessment calculations don't change when we make changes to the model in future.

Future plans

We're working implementing a new report template which will come along with better quality PDF generation. We expect this to go live in February or March.

We also anticipate some usability improvements to the solar hot water page to come online in the next weeks.

This August we made only a couple of user-visible changes:

• The 'commentary' page now correctly shows the heat loss information for each scenario rather than just the baseline scenario repeated over and over again.
• We upped the maximum file upload in the image gallery from 10MB per file to 25MB, after a complaint that a particularly large photo wouldn't upload.

Helpdesk system

We've started using a helpdesk system for support. The new system will let us help you quicker – and should mean you don't have to CC multiple people in to answer a simple question! It'll also help us to improve the app, as everyone on the team will be able to see what issues are coming up regularly.

So, from now on, please email us at support@retrofitplanner.app.

Next version

We continue to work on the next version, HRP v3, and we'll post about that more in due course. We're planning to get it out before the end of the year.