Condensation issues, I have been recommend to fit a PIV ( Positive Input Ventilation) Unit

justwondering25

FreeBear said:

deannatrois said: The lack of vents in the windows/drying of clothes on radiators may be the cause, but to be honest, most houses should cope with this unless the tenant was running a professional laundry business (or has masses of clothes to wash and dry).  I'd check for other problems as well.

Similar age property here. No extractor in the (small) bathroom, and we regularly dry clothes over radiators & banisters. The windows are generally kept firmly shut during the winter, and condensation hasn't been a problem. I try to maintain the temperature above 18/19°C, and it has been ~24°C in a couple of rooms this past winter.

If I were to fit a PIV system, it would have to be combined with a heat recovery unit - No point in keeping the place warm if half the heat is being pumped outside.

Your very lucky with your condensation situation, but I would recommend reading up on the wonders of the PIV units, you might be surprised how well it would fit your needs. 

justwondering25

deannatrois said:

Is it worth putting trickle vents in some windows?  If you look on Youtube, it can be done.  I don't know if that will be cheaper than a PIV system.  I had one of those in the ground floor hallway of a three storey maisonette.  It made the ground floor really really cold but didn't have enough power to push air into any of the upper stories.  It didn't stop the mould problem at all (putting insulating wallpaper on the walls did as cold external walls was the cause of the problem.., you touched the affected mouldy walls and could feel they were colder than other walls).  It was a very easy fix.  BTW I never dried clothes on radiators.

The lack of vents in the windows/drying of clothes on radiators may be the cause, but to be honest, most houses should cope with this unless the tenant was running a professional laundry business (or has masses of clothes to wash and dry).  I'd check for other problems as well.

Unfortunately a person's lifestyle is often blamed for condensation (like, "stop breathing in your house, did you realise you are breathing out four cups of moisture each and every day, you monster?").  I agree with POP that a house should be able to cope with humans living in them without having open windows dripping icicles onto its inhabitants.

We currently rent a flat in a 15th century Hall, lovely place, but no vent in the bathroom, the mould definitely builds up due to the condensation due to the shower, we have two choices run a dehumidifier or open a window, both do the trick, if not the ceiling quickly starts to show the black mould spores, air flow is the answer, I could blame it on the building, but I know the answer, or a extractor fan, but that once again is airflow. 
With regards to fitting the PIV on the lower level of the building, from the fitting guides I have watched on YouTube, that seems to go against how the system works as it needs a loft type area for the air to begin with... 

Phil4432

justwondering25 said:

Has anyone had any past experience with a PIV unit to help combat condensation?
My tenant of the past 4 years is about to leave, one thing he has done and it can be seen on the estate agents inspection reports, is that they have been drying clothes on radiators etc.
Which has caused condensation which has led to black mould.
The double glazing does not have any inlet vents, so unless the tenant opens the window, or turns on the fan in bathroom, then there is little airflow in the building, other than a couple of building brick vents two of the bedrooms.
I was reading up about condensation fixes and I watched a couple of Youtube videos and a lot of people seemed very positive about using a PIV unit, the unit is fitted in the loft and actively circulate the air in the house, low powered and quite too.
The reviews for the various units available online via the various big main online shopping venues, seem very positive and so did the comments on the youtube videos of people that have used them.
The house is a centrally heated doubled glazed 1930's semi.

I've solved a condensation problem in my mums 30's semi.
The problem with her house, was that like many semis of the era they were built with chimneys and single glazing in mind.  Then double glazing came along, which was great, but along with blocking the chimneys restricted circulation in the house.

Once the mold had been removed, the solution has been rather simple.  An ebac dehumidifier, and opening the windows for hour per day every day.  No drying clothes on radiators, and open the kitchen windows while cooking, bathroom windows while showering and for an hour or so after a bath/shower.  Keep the bathroom door closed.  Keep the windows on 'latch,' as much as possible.  Check the spots susceptible to mold every month or so.  Keep the house temp above 14C at least.   I was going to get some vents installed also, but there has been no need up to now. 
  I'd try the above first, will cost you the price of the dehumidifier which is around £200 or less.

justwondering25

Phil4432 said:

justwondering25 said:

Has anyone had any past experience with a PIV unit to help combat condensation?
My tenant of the past 4 years is about to leave, one thing he has done and it can be seen on the estate agents inspection reports, is that they have been drying clothes on radiators etc.
Which has caused condensation which has led to black mould.
The double glazing does not have any inlet vents, so unless the tenant opens the window, or turns on the fan in bathroom, then there is little airflow in the building, other than a couple of building brick vents two of the bedrooms.
I was reading up about condensation fixes and I watched a couple of Youtube videos and a lot of people seemed very positive about using a PIV unit, the unit is fitted in the loft and actively circulate the air in the house, low powered and quite too.
The reviews for the various units available online via the various big main online shopping venues, seem very positive and so did the comments on the youtube videos of people that have used them.
The house is a centrally heated doubled glazed 1930's semi.

I've solved a condensation problem in my mums 30's semi.
The problem with her house, was that like many semis of the era they were built with chimneys and single glazing in mind.  Then double glazing came along, which was great, but along with blocking the chimneys restricted circulation in the house.

Once the mold had been removed, the solution has been rather simple.  An ebac dehumidifier, and opening the windows for hour per day every day.  No drying clothes on radiators, and open the kitchen windows while cooking, bathroom windows while showering and for an hour or so after a bath/shower.  Keep the bathroom door closed.  Keep the windows on 'latch,' as much as possible.  Check the spots susceptible to mold every month or so.  Keep the house temp above 14C at least.   I was going to get some vents installed also, but there has been no need up to now. 
  I'd try the above first, will cost you the price of the dehumidifier which is around £200 or less.

Hi, Sadly that is great for a owner occupier, but sadly when it comes to a tenant , asking them to do all those things is well in the hands of the gods, with your mums house been her house, she has a big incentive to do those things.
The PIV unit adds an element of automation to the airflow in the house.
I agree with all your points though, they are all worthy and well worth pointing out...

pippersJpippinton

ProDave said:

You already know the cause of the condensation and mould, drying clothes indoors.  I am willing to be he under heated the property, never opened a window, turned the bathroom fan off etc.

We had one tenant like that who managed to cause condensation and mould where no tenant before or after did,

Top tip. NEVER have a fan isolator switch in a rental property so the tenant cannot disable the bathroom fan.

Do not follow this advice. The wiring regs are very clear that a fan MUST have an isolator for maintenance which switches all poles. I'm a landlord with 20+ years experience and a domestic commercial and industrial electrician.

Wyndham

We have a PIV which was installed a couple of years ago. We have a bungalow with a big footprint, and it has really helped with the airflow through the house, and reduced the amount of mould. I'd recommend it!

silvercar

Wyndham said:

We have a PIV which was installed a couple of years ago. We have a bungalow with a big footprint, and it has really helped with the airflow through the house, and reduced the amount of mould. I'd recommend it!

Does it cause a drop in temperature? It’s replacing indoor air with outdoor air, so if it is cold outside it may mean losing heat.

ProDave

pippersJpippinton said:

ProDave said:

You already know the cause of the condensation and mould, drying clothes indoors.  I am willing to be he under heated the property, never opened a window, turned the bathroom fan off etc.

We had one tenant like that who managed to cause condensation and mould where no tenant before or after did,

Top tip. NEVER have a fan isolator switch in a rental property so the tenant cannot disable the bathroom fan.

Do not follow this advice. The wiring regs are very clear that a fan MUST have an isolator for maintenance which switches all poles. I'm a landlord with 20+ years experience and a domestic commercial and industrial electrician.

4 year old thread resurection alert.

Please quote me the regulation that says a fan must have an isolator?  I have never found it and repeated attempts in multiple places for someone to quote me the reg have failed to get a response.

If you have to have one, fit it in the loft out of tenants reach, or you would think someone would make a fish key operated isolator.

Wyndham

silvercar said:

Wyndham said:

We have a PIV which was installed a couple of years ago. We have a bungalow with a big footprint, and it has really helped with the airflow through the house, and reduced the amount of mould. I'd recommend it!

Does it cause a drop in temperature? It’s replacing indoor air with outdoor air, so if it is cold outside it may mean losing heat.

No - or at least, not that we've noticed. We honestly don't really realise it's there. There is a 'draft', but you have to be right up by it to feel it - my tall husband can get close enough, I have to be on a step ladder!

And it has made a difference to the mould.

BobT36

Wyndham said:

silvercar said:

Wyndham said:

We have a PIV which was installed a couple of years ago. We have a bungalow with a big footprint, and it has really helped with the airflow through the house, and reduced the amount of mould. I'd recommend it!

Does it cause a drop in temperature? It’s replacing indoor air with outdoor air, so if it is cold outside it may mean losing heat.

No - or at least, not that we've noticed. We honestly don't really realise it's there. There is a 'draft', but you have to be right up by it to feel it - my tall husband can get close enough, I have to be on a step ladder!

And it has made a difference to the mould.

Do you have the heated version or no? 
And is it just pulling it from your loft or the outside? 

I've heard good things about these. Any specific brand you have?