Opinions please- MVHR historic listed house

[JoelR]

Hi All,

 

Looking for input here.

I have a very old thatched, limestone wall house (1.5m thick in some places) that I am undergoing a total restoration and upgrade, including a small extension. I will be insulating the roof from inside under the thatch, and most of the walls with breathable insulation on the inside. We have planning for double glazed windows, and new front and back doors. 

I am doing the build myself and am paying a lot of attention to fixing all the small air leaks. Most of the inside will then be plastered in lime, creating a good air seal.

 

I intend to install a MVHR (looking at Sentinel Kinetic Advance) myself, looking to spend about £2k. I have space in the loft for it, and can run ducting through stud walls to most rooms, although to limited areas downstairs due to thick walls and no ceiling void.
I would likely not be able to get ducting to the extension two rooms, it's downstairs room with have a humidistat extract fan as it will be a sports store room and be closed off mostly.

 

I don't believe I have any building regs to meet with this as the building is listed. The regs officer is very relaxed about the work I've done so far, saying he is happy with any upgrade to the house.

So the point being- I can get ducting to all bedrooms, but not all of the house. I want the system to keep the house air fresh, filter pollen and allergens, keep the house dry and save some of the heat that would go out of the window otherwise. It isn't much upheaval as lots of work is being done anyway.

 

So I'd like advice please on how I could design the system, and whether its worthwhile installing it? Also whether it would likely work inefficiently or not at all, being that the house won't be 100% sealed as a new build could, and that the system could only move air in most but not all rooms?

 

I have spoken to people in a very similar house who have installed MVHR and sing its praises, but would like other input before spending a lot of money and time.

Thanks!

[joe90]

Generally the less the house is air tight/draught free the less efficient it will be, however if you know of people that have done it in similar houses and like it then it sounds ok.

[SteamyTea]

I suspect you are really after temperature and humidity control.  Standard MVHR is not going to help much there.

 

[Seeoda]

On 08/05/2023 at 17:47, SteamyTea said:

I suspect you are really after temperature and humidity control.  Standard MVHR is not going to help much there.

 

 

The MVHR wont help with temperature but it helps a load with humidity. But we'd be able to advise more if they explained if they had a blower test. I think that is the way to go. 

[JohnMo]

I would look up and have a read on cascade MVHR.  But also read up on condition based dMEV, where the inlet and inlet is humidity controlled only ventilating when required.