passivhaus design - initial ideas
February 12, 2013
So, we are currently working on our initial designs for the house....
There are lots of aspects we are trying to combine at the moment, given our restricted budget and the passivhaus criteria, some of which conflict with each other.
I read an interesting article yesterday in the 'Products in Practice' supplement that came with this month's RIBA Journal entitled 'Moisture in Buildings'. It seems the issues of not detailing correctly / monitoring construction closely enough in low-energy buildings can have pretty serious consequences! Not sure if the article is available online but I will hunt around and see....
One of the main issues seemed to be related to both incorrect specification of the MVHR systems and the lack of adequate transfer openings between rooms that allows the air to pass from the supply vents, through the building and to the spaces with the extract points. Serious problems were discovered when the warmed moist air couldn't leave the building and was effectively trapped causing serious moisture build-up and damp issues. Especially important in our climate when the amount of time in the year when washing can be dried outside is often minimal.
So, needless to say, today's main issue that I have been considering is how to make the transfer openings large enough but in an aesthetically pleasing way, and without compromising the acoustic separation too much between rooms....
We are hoping that by off-setting doors, i.e. never having 2 doors to main rooms directly opposite each other, that will help to eliminate any acoustic issues, but I think a bit more investigation is required!
We are thinking of using sliding doors internally and want to have a minimal appearance to the openings, so I found this product on Hafele's website:
It is a patented system where the sliding mechanism is all concealed by the door: voila: an air space is created between the door and the wall and the need for a traditional architrave is eliminated! :-) So now all I have to figure out is whether this will give the right quantity of transfer opening and in the right place around the opening!