Air change rate - fresh air flow rates

[daz1984]

Hi all, 

 

Trying to calculate the air change rate, the basic formula I've found on google specifically asks for fresh air flow rate. Is there any assumptions made with this figure? I'm not even sure where to start on calculating an accurate figure. We do have a log burner in the lounge so I assume this would maybe cause some fresh air flow? Bathroom fans? But in terms of quantifying a figure I'm at a loss.

 

For some context I'm trying to calculate what size, roughly, ASHP I would require - i appreciate this has been covered many times. I've found a spreadsheet on here so i'm trying to work through that for predicted heat loss.

 

Apologies if this has been covered elsewhere, maybe I'm searching inaccurately.

 

Cheers

Daz

[SteamyTea]

Have you downloaded the Building Regulations.

They are worth having a read of.

Part F covers ventilation.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/468871/ADF_LOCKED.pdf

Edited October 20, 2019 by SteamyTea

[Jeremy Harris]

Also worth reading the compliance guide, as well as Part F, plus the NHBC guidance and, perhaps, also the PassivHaus guidance, as all are useful:

 

NHBC MVHR Commissioning.pdf

 

Passivhaus MVHR Commissioning Requirements V121.pdf

 

domestic_ventilation_compliance_guide_2010_edition.pdf

[daz1984]

@SteamyTea @JSHarris thank you! i will do some reading