innercitadel

That should work if you bring it to the soffit instead of a different room. However youre paying extra for the temperature sensor. Don't get the air from the attic, it's not healthy air, I don't care how good the filters are, it is something unheard of elsewhere in the developed world. I would rather have nothing than air come in from the attic. Please rid yourself of the idea of venting from the attic.

I have these links saved in my bookmarks when I first researched this 10 years ago and retrofitted a ducted HVAC system in my previous house.

https://www.energyvanguard.com/blog/Case-Closed-Get-Those-Air-Conditioning-Ducts-out-of-the-Attic

https://www.nrel.gov/docs/fy10osti/48163.pdf

In many countries in Europe houses actually have to have their ventilation/insulation performance tested and pass the test (e.g. blower door for air tightness). We have gotten better at insulating but our builders still don't generally understand the importance of mechanical ventilation. Cue Mouldy homes chapter 2.

Balanced heat recovery mechanical ventilation > positive pressure ventilation > negative pressure ventilation > nothing > air from the attic.

Just my opinion. I don't work in the industry. Just a geek.

Oh wow mechanical heat recovery systems have jumped in price. They were 2-3k a few years ago. The way mechanical heat recovery works is kind of like penguin legs. The inflow and exhaust airflows pass by each other. So the warm exhaust air passively heats the cooler inflow air. So they are quite basic things that are very cheap to run. I guess another kiwi tax. Done some googling for pricing and it does appear 5-6k is the going rate now. E.g. another option: https://www.smooth-air.co.nz/home/hex390

What about something like this: https://www.smartvent.co.nz/why-smartvent/ that should also improve the humidity. Doesn't say price though. They seem to have a variety of options including positive pressure which should be much cheaper than a heat recovery system. https://www.smartvent.co.nz/smartvent-positive-advance/

Here's some more information about heat recovery systems and why DVS/HRV from the attic are shit. https://www.smarterhomes.org.nz/smart-guides/heating-cooling-and-insulation/ventilation-and-heat-recovery-systems/

You mean a split system? A heat pump usually refers to a split system which doesn't have the V in HVAC as it just recirculates air. HRV is the ventilation from the attic thing, please don't get that.

HVAC generally refers to ducted aircon with mechanical ventilation. The "heat pump" sits in the attic. Fresh air is taken in from the outside through the soffit. Ducts run from the "heat pump" into each room.

If a ducted system is too expensive then you should install plain mechanical positive pressure ventilation from the outside (not HRV/DVS) Depending on your house it is possible to DIY this using stuff from Bunnings. You could even link the fan to your Home Assistant and get it to activate when the humidity reaches a certain threshold. This should fix your problem. If it causes the house to get cold by doing this then you could install a mechanical heat recovery device.

Thanks for further details. I would definitely invest in getting HVAC installed in that instance or if cost is an issue then at minimum install simple positive pressure mechanical ventilation from the outside into the bedrooms. This should fix your problem. It sounds like windows aren't enough because the house is well sealed, so you need a mechanical solution. Please don't get DVS from the attic.

I live in a new house with HVAC and leave the mechanical ventilation on when not heating or cooling and it keeps moisture levels low. I also got HVAC retrofitted into my previous house which made a massive difference in moisture. I'll never live in a house without HVAC in the future if I can help it.

What do you mean exactly you ventilating. Mechanical ventilation?

Modern houses NEED mechanical ventilation. It's a travesty that new houses in NZ don't come with mechanical ventilation as standard, as is done in the rest of the developed world.

It's pretty obvious if you think about it. Seal the house well, well insulated, double glazed. How will the moisture leave without ventilation. This is why modern houses NEED mechanical ventilation. Older houses don't need mechanical ventilation because the house is already leaky.

And not the silly DVS thing. I don't want rat infested air from my attic thank you. I don't care how good the filters are. Ventilation from the outside please.

What this looks like is intake vents in the soffit, a duct, and fan that pumps fresh air in for positive ventilation. Our you can do negative pressure where it pumps out, or balanced where you have air coming both in and out. You can install a mechanical heat recovery system if the house gets cold.

Full HVAC includes ducted heating/cooling.

TLDR: your house is humid because it's well sealed and the builders couldn't be bothered putting in mechanical ventilation because we are 20 years behind the rest of the world.

If you already have mechanical ventilation then it is likely not installed properly. Just putting it in doesn't necessarily mean it's sized correctly for example.

There is some British stuff on Usenet (e.g. nzbGeek) but yeah in general I have concluded that British TV doesn't have broad appeal and so it is hard to find even if willing to purchase.

You could also try using a VPN with the BBC iPlayer app. I've done this before.

There is also the acorn TV app which is a paid streaming service, $8 a month, and probably the best option if you're really into regularly watching British TV as there isn't really a great alternative option.