David Lam

Thanks Russ. BPC have said commissioning may be tricky. However reading on this forum leads me to think most people aren't that fussed about being that precise in the commissioning process.

Hi all Can I request your valued opinions please? I think most of my duct runs are simple, except for the kitchen extract which has to run from the loft down into the kitchen on the ground floor. The only way I can think of making it work without making holes in brick walls is to sneak under the kitchen doorway (with no door) and use a linear diffuser like this: https://www.ventilationland.co.uk/product/35018/slot-diffuser-with-2-adjustable-slots-of-700-mm.html This would have to sit inside a bespoke-made plenum that I can make out of plywood with 2No. ducts entering from above. I've sketched up a simple plenum which I've attached. I've also attached photos of where the plenum would sit for context. The blue lines are supposed to be ducts! Is this going to work? Any issues you can think of? Thank you D

Thanks both. I'll see if BPC can sell me something like that.

Aha! Well it sometimes takes a genius to recognise genius. Did you buy something off the shelf or did you have to have it bespoke made? Thanks!

Wall. I've attached a photo of what it looks like. The alternative is to go through the soffit, but it's pretty narrow. Probably big enough for 100mm duct. The intake/exhaust ducts on the unit I'm thinking of (VentAxia) is 125mm. BPC has said I could reduce from 125mm to 100mm, but that sounds problematic to me. Much appreciations! D

So BCP has suggested their cowl for going out of the wall. https://www.bpcventilation.com/exterior-grille-s-steel-louvered-cowl However I'm worried about the waterproofing of the tiles. Is this something that is standard? I suppose I could remove the tiles, cut a circular hole in them and put the cowl through but this seems a bit bodgy. Does anyone have any ideas? Cheers! David.

Ah, okay. Thanks for trying! They do look pretty similar from this angle.

Excellent! Thanks @mike2016, super useful. Would you be able to post a picture of what they look like on your roof please? I'm intrigued how you dealt with the intake and exhaust separation. Cheers David

Hi Conor Genuine question as I'm trying to do a similar thing - is the 80kPa static pressure in the ducts? If so do you not mean 80Pa? Or is it something else? Fingers crossed for the Smartys. Only they have the answer! P.S. @Ryan BazeleyIf your contact at Solarcrest is Nathan, he's a good guy. He's done the Passivhaus designer's course.

Good to know thank you. Will that also work for the intake?

Thanks both. I haven't checked the tiles yet, but they're for the wall of the dormer, not the roof. I was hoping to find an image online that showed me what I was looking for, but havent' been successful. I was expecting to be able to see a ductwork cowl poking out with some neat flashing around or something. Does the Ubbink tile vent allow the bit I've circled to come off? Sorry, I just can't see how it works if you're trying to throw the exhaust air away from the building.

Hi all First post from me! I'm retrofitting an MVHR system into my new loft and am thinking about where to place the ducts to atmosphere. They could come out of the front of the house through brick. However there's limited space for the MVHR unit due to the pitch of the roof and I want to put the unit close to the facade. Alternatively they could come out of the rear of the house through the tiles in the dormer. However I can't find a product on the internet that will allow a neat solution to dress around the ducts as they exit. Does anyone know how to do this? I'm not in the country at the moment so can't show photos, but this is the kind of tile in the screenshot attached. Thank you! David