Window openings & MHRV

[Gill]

Stupid question o'clock... 

 

I'm trying to finalising a window schedule on our renovation. The plan is no trickle vents and short term the lack of insulation and various ancient extraction will provide plenty unwanted ventilation. We plan to add ventilation via MHRV as we improve insulation and air tightness. 

 

I'm wondering if I've reverted to form with the window schedule by adding openings (6 out of 9 windows) when I might not need. 

 

We're close to a busy road so aside from heavy kitchen cooking we rarely opened windows over the summer.  

 

Any experiences to draw from would be much appreciated. Is it better to have the option or is it something you thought was necessary but never actually use ? 

 

Thanks 

 

 

[Conor]

You need openable windows for escape in some scenarios but also for rapid ventilation. It'll be noted on your approved building control drawings (if applicable). 

[Gill]

Thanks Connor - that makes sense. Building control not an issue for us but you never know know when you'll need an emergency exit. I think I can tone the window openings down a little and keep them in rooms that don't already have alternative exits. 

[JohnMo]

Remember MVHR is ventilation only, it does not provide enough flow to cool the house in summer.  You have windows that open to allow cross flow ventilation to provide cooling as much as anything else.

[Gill]

Will look at optimising airflow and save the fixed field for rooms with at least one other window.  I probably wasnt far off with my first plan but then the doubt crept in.