Door gaps

[Rossek9]

Our timber frame manufacturer has emailed today to ask about our door gaps for our airflow requirements.

 

Is there a standard size for this for mvhr?

 

Thanks in advance.

[lizzie]

No one has asked me that, not to say it has not been covered by builders but no one has mentioned it to me and my doors will be going on soon so following with interest...timely post for me!

[Construction Channel]

6-8mm according to this. 

http://www.ebuild.co.uk/topic/15502-gap-under-doors/

[jack]

Check your building inspector doesn't want more. There's some official-ish document around that suggests 10mm if I remember correctly. It's based on the width of a small imperial door and anticipated flow rates - something like that.

 

Edited to add: Knew I should have searched before posting. Here it is: http://www.titon.co.uk/pages/knowledge-support/building-regulations/part-f-ventilation-england-wales.php

[Mr Punter]

I do 8mm under doors but please bear in mind floor finishes.  If I have 20mm engineered wood I lay this first, then door lining / frame on top, so calculate structural opening height from this.  Flooring such as carpet can take a fair amount of height so the lining / frame height may need to be a bit taller or you will need to cut the bottom of the door to get the required space under.

[Rossek9]

Thanks for the replies folks.

 

The timber frame guys are saying they normally allow 20mm which should be fine tbh as we are having vinyl throughout most of the house which is around 5mm. That will leave 15mm for airflow.

[le-cerveau]

It should be 10mm for a standard door, 7600mm², as described in the Domestic Ventilation Compliance Guide, which is the Approved methodology for the building Regulations.

Extract of the MVHR testing and commissioning guide.