EPC rating destroyed by Positive Input Ventilation (PIV)?

Reply to the comment left by East Midlands Energy Efficiency at 30/08/2023 - 15:16
What is the effect of installing heat-recovery ventilation fans in wet rooms?

Reply to the comment left by Luna at 30/08/2023 - 15:35
That’s interesting! Mine wouldn’t change unless we paid for new epc . After moving in we found we had cavity wall insulation, we also have air ventilation system .

Reply to the comment left by Teessider at 30/08/2023 - 10:10
Wow

Many of the conditions we face in older property is addressed in the government's specifications for retro fitting existing dwellings. They fall under Building Control (apparently)!
Whilst positive pressure works to change the air and hence quality of the air it doesn't recover the heat exhausted as it does so, for that you need Heat Recovery Ventilation.
In theory this satisfies the EPC requirements - but I have an observation, one which I have discussion with my local Fire Officer, it goes as follows:
If each room is vented and ducted to a central point in the loft a,system which is approved by the government, then it stands to reason that the ductwork breaches the horizontal fire breaks in the ceilings, therefore the fire integrity of each room, into the floor void of the bedroom above.

The fire officer agreed that this is not desirable and would be very expensive to secure, adding he had not even heard of these new requirements ! Surprise, suprise.

Reply to the comment left by Mick Roberts at 30/08/2023 - 10:53
May I asked what is the cost to install this Please.

thanks
wanda

Reply to the comment left by Teessider at 30/08/2023 - 10:10
"Damp and mould are caused by faults within the fabric of the house. PIVs only deal with the symptoms, not the cause."

Nonsense. That can be the cause, but not exclusively. Poor ventilation is much more likely than structural issues.

The units are about £300 on Amazon. The Brands are Kair Kalahari, Nuaire DriMaster and Vent Axia PureAir Home PIV. It is just a hole in the ceiling at the top of the stairs and wires into the lighting circuit - maybe £175 for the electrician. They work for damp and mound problems. Very well. I am running them in five 1900s properties.

There great. Ideal for problem tenants

Reply to the comment left by wanda wang at 30/08/2023 - 21:51
Envirovent charges something like £1000 fitted & they insist you have their expensive very good bathroom & kitchen fans too for the sort of guarantee.
I went for the https://nuaire.co.uk/
Was about £350 & Electrician about £80 to fit it from memory.

A few notes here over the past, there will be more experts on here than me & these notes. Lot of detail, but it may help some of u:

Once every 5 years, Clean filters on fan in loft, I have instruction book. Nuaire.co.uk Tel 0292 085 8400
Replace filters every 5 years Sep 2024
June 2019 & Dec 2021 had a new whole unit under warranty.

Dec 2021 Lena said no condensation and Unit blowing warm air. Any less water on walls? Lift Nuaire cover off, turn up blue dial screwdriver round & button to 2 which is humidistat Dale says, which is comes on at lower temperature.
Dale £50 fitted Nuaire unit replaced by Nuaire 10? Dec 2021. Guarantee 2024 bought from ebay in messages & emails in Rowe. Dale said 3 amp fuse so shun't use a lot of heat.

I would also make sure the loft unit is on quite a high setting as there are 5 people in the house and it maybe that with these measures the boarding out of the bay windows may not need doing but is something to keep an eye on in the Autumn as night time temperatures drop.
Another thing to consider would be to check that the loft is properly ventilated as for a PIV unit to work effectively it does need a supply of fresh air, did the property still have condensation problems last winter even though the PIV had been installed?
Code: DRI-ECO-HEAT-HC
DRIMASTER-ECO-HEAT-HC (In Home Controls RF enabled WITH HEATER)
It's Drimaster ECO Heat HC 7 year warranty bought 13 March 2017 ebay
Item number 122340180247
Please contact Nuaire Technical in the first instance to see if they can diagnose over the phone (02 920 858 4 00, option 1).
http://www.nuaire.info/IandM/671755.pdf

Turn up fan unit in loft. Digits should see.
Blue temp button mid point is 10 degrees.
Dec 2021 all settings
https://youtu.be/0IpURInmo_I

https://youtu.be/SeguWaAYyeM

https://www.youtube.com/watch?v=BzBpBELbR8Y
Check bathroom fan isn't just blowing damp humid air into the loft to be blown back into the house by the PIV ie make sure it's vented outside.
Possible roof tile vent if can't see any daylight fresh air coming in.
Dale said he fitted bathroom extractor & Dec21 checked, it is still ventilated to outside properly.
Mouldstop https://www.ebay.co.uk/str/mouldstop
Email: info@mould-stop.co.uk

Envirovent Cyclone 7 230v Filterless Bathroom & Kitchen Extractor Fan
Thanks for the call and as we discussed the installation of Cyclone 7 extractor fans through the wall in the kitchen and bathroom at XXX would greatly improve the ventilation. The cost for this would be £399 + VAT each and includes the core hole and electrics and the fans have a 7 year parts and labour warranty. The unique selling point of the Cyclone fan is not only it’s long 7 year warranty but also the fact that as they have been specifically designed for the rental market they require no user intervention but rise and fan in speed in direct correlation to rises and falls in humidity.

I would also make sure the loft unit is on quite a high setting as there are 5 people in the house and it maybe that with these measures the boarding out of the bay windows may not need doing but is something to keep an eye on in the Autumn as night time temperatures drop.

Another thing to consider would be to check that the loft is properly ventilated as for a PIV unit to work effectively it does need a supply of fresh air, did the property still have condensation problems last winter even though the PIV had been installed?

Reply to the comment left by Mick Roberts at 31/08/2023 - 07:34
Thanks Mick for all the information, it seems not just electrician but does it also need a roofer to get the hole in the roof?

Thanks

wanda