# New in May 2026

### Updates

<div id="bkmrk-heatpunk-uk-has-been">- Heatpunk UK has been updated to enact various MCS changes to operating temperature and air change rates. 
    - [Operating temps for post-2006 buildings have been increased in almost all rooms](https://heatloadcalculator.mcscertified.com/docs/reference-sources/design-conditions#design-room-temperatures).
    - [Air change rates now default to 0.5 for all rooms except internal](https://heatloadcalculator.mcscertified.com/docs/reference-sources/ventilation-rates#minimum-room-air-change-rates).
    - [Using the standard ventilation method now uses a fixed default air permeability of 12 m³/h.m² @ 50 Pa rather than using an occupancy-based estimator as before.](https://heatloadcalculator.mcscertified.com/docs/reference-sources/ventilation-rates#standard-airtightness-method)
- Skip button added to consumption task menu.

</div>### Fixes

- Correction to post-2006 room temperatures when using specified air permeability.
- Fix to errors caused by deleting region corner with a height.
- Floor plan task can now handle materials that have u-value of 0.
- Sidebar displays correctly when opening material library from home page.
- Fix to floor plan PDF upload when there is more than one page.
- Emails no longer all show as sent based on one email.