Would be interested to know if anyone has used the Lunos ventilation system and, if so, their views on it. We are building an extension to passivhaus standards onto our old stone cottage (extension will be about a third of the total size). We've replaced all existing windows with Internorm triple glazed windows and will have those in the extension too.

We'll need ventilation! Have discounted a full MVHR system as overkill (old cottage walls will still be a bit leaky no doubt) and too destructive to the old cottage. Had thought about an Envirovent PIV system with heatsavas in 3 or 4 rooms (7 rooms in total in finished cottage) but have come across the Lunos e2 and ego systems. Any thoughts will be extremely welcome, and thanks in advance

Go full MHRV, go for cheap ones with heat recovery, you will love it, even two small plastic or polystyrene whole house ones would do available from the web for several hundred quid. add DIY ducts designed in and it will be ok.

If you search the forum we have discussed this a little before. We had a thread a few months ago. Also the Home Style Green podcast had a NZ reseller talking about the system.

In principle it seems good for retrofit but it depends on the costs.

Think long and hard!
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=10274

If you can hang on for a year I should be able to comment. We are fitting 7 units as part of our Listed Building Consent to "protect the fabric of the building" in our old stone farmhouse.

Posted By: gravelldDifferent type of system, Tom

The OP mentioned multiple Heatsavas

Posted By: gravelldReally looking forward to hearing about that!

How was BC consent? Is there an overall air permeability target for the building? Is adding these units the only work?

Who did the design for the layout and did they help you with BC?

Took us 4.5 years to get LBC with big thanks to Joiner on here for the design of the 3G windows direct into the stone mullions with expanded foam seal and burnt sand mastic window pointing. Replacement of external doors with oak sealed outward opening swedish doors. So trying to be pretty air tight but using lime mortars and plasters to allow the building to breathe. Also have 3 en-suites to install plus a Jack and Jill bathroom as well as 2 kitchens and UFH. Design I did myself but LBC application was a specialist as I had a previous run in with the council over a simple agri building which took 7 yrs to get permission and we won on appeal.

Posted By: gravelldWhat about ventilation requirements though, did you need specialist for that, and was it a Lunos/Partek person?

Do the windows have trickle vents?

Windows totally sealed hence using the Lunos. The house is basically a T shape so we basically have 4 large rooms with 2 lunos units in each room at diagonal opposites which just happen to be en-suite/kitchen on 2 floors and ensuite/jack & jill on the other. The final room is living room/snug with 2 chimneys plus 2 woodstoves with external air supplies. All internal doors have gaps top and bottom to allow air to circulate. Seventh unit is for stand alone kitchen and is not a linked unit.

Calcs were all done using data supplied by the Germans as usual very efficient. Just hope it all works in practice as what used to be a very draughty old farmhouse is certainly far more sealed then it used to be and we still have to fit the swedish doors.

Posted By: gravelldThat's good news, I was wondering whether BC would be happy with the ventilation provided by a non-ducted system.

I have no grounds for thinking that, other than BC's knowledge of the area not being adequate and so them pushing back.

The seventh kitchen unit - is this heat recovery and do you have a separate recirculating hood?

The units used in pairs are E2 the stand alone in the main kitchen is an Ego which includes heat recovery and we dont have a separate recirculating hood as we use an Esse wood burning range.

Also note being listed we where not allowed any penetration of the fabric of the building. The compromise we had to come to was the white plastic cover was replaced with a matching sandstone tile drilled with ventilation holes and hidden behind the wooden spoutings and cast iron square down spoutings.

Posted By: gravelldHow does the Esse negate the requirement for cooking ventilation? I realise they are vented inside the ovens, but what about the hot plates?

The kitchen is quite small and detached from the rest of the house so cooking smells do not travel into the main house and the Ego is powerful enough to extract as well as get rid of any condensation.

Yep, please report back!

So turn it off then on again?

Holy thread revival.

John, Over one year on, what is now your opinion of the Lunos units, as I am considering then them for an extension that we are doing.

RenewableJohn, Thanks for this. Can I ask where you got them from? I can only find an Irish supplier.