Demand control Ventilation? Positive input ventilation? Reviews.

bcoll05

Hi.
I need reviews from people who have installed Demand Control Ventilation or Positive input ventilation.

*I don't want heat recovery so no need to bring the subject up on this thread. To expensive.*

I am renovating a 20 year old house. Pumping walls & dry lining walls. Trying to get the house relatively airtight.
I need Ventilation so I am looking for feedback on systems people have installed in their homes & what there view is of those systems.
Money well spent?
Notice the difference in air quality?
Happy with their system or regrets?
Any flaws in the system?
Would they change their system?
Any information is greatly appreciated.

Calahonda52

The LCCA for MVRH, when higher interest rates and energy prices are costed in makes it cheaper than DCV/PIV

https://www.wbdg.org/resources/life-cycle-cost-analysis-lcca

MicktheMan

bcoll05 wrote: »

Hi.
I need reviews from people who have installed Demand Control Ventilation or Positive input ventilation.

*I don't want heat recovery so no need to bring the subject up on this thread. To expensive.*

I am renovating a 20 year old house. Pumping walls & dry lining walls. Trying to get the house relatively airtight.
I need Ventilation so I am looking for feedback on systems people have installed in their homes & what there view is of those systems.
Money well spent?
Notice the difference in air quality?
Happy with their system or regrets?
Any flaws in the system?
Would they change their system?
Any information is greatly appreciated.

My advice is not to use PIV, but MEV instead (pumping moisture laden air out through a cool structure is never a good idea). The MEV infrastructure can then be reused if an upgrade to DCV is ever requited. Level of airtightness achieved will also impact on decision between MEV and DCV.

Wartburg

I think PIV is not the best idea in regards to the pollution in your attic space, because you´re pumping air from your attic space into your habitable space. The most attics are covered with mineral wool insulation or spray foam. I have serious doubts that the integrated filters in the PIV units are suitable to filter the tiny fibres of the insulation material.
DCV is getting more poular as a low-cost ventilation strategy, especially for council houses. Their idea is, to have no mechanical parts and maintenance involved. The backside of the coin is, that DCV is not continiously supplying fresh air and the most buildings require a functional ventilation strategy for 24/7.
As MicktheMan stated, the MEV could be an option for your home. In this case it´s definitely worth to consider the use of suitable background vents, which can be upgraded to decentralised hrv units at your own convenience. You might will have a requirement for hrv in the future, that´s why be prepared.

MicktheMan

Wartburg wrote: »

The backside of the coin is, that DCV is not continiously supplying fresh air

Can you elaborate on this please.

Wartburg

MicktheMan wrote: »

Can you elaborate on this please.

I´m might a bit outdated about DCV, but I have all the time a particular French company in mind when it comes to DCV. They sell vents for walls and windows with a built-in humidity sensor. Their vents open mechanically as soon as you reach a certain level of humidity inside of your room. Am I wrong or right?

MicktheMan

Wartburg wrote: »

I´m might a bit outdated about DCV, but I have all the time a particular French company in mind when it comes to DCV. They sell vents for walls and windows with a built-in humidity sensor. Their vents open mechanically as soon as you reach a certain level of humidity inside of your room. Am I wrong or right?

In combination to what you describe there is also a (constant pressure) exhaust fan (long life, low power) connected to the wetrooms, therefore 24/7 functional ventilation.

So you're right and wrong:)

Wartburg

MicktheMan wrote: »

Can you elaborate on this please.

MicktheMan wrote: »

In combination to what you describe there is also a (constant pressure) exhaust fan (long life, low power) connected to the wetrooms, therefore 24/7 functional ventilation.

So you're right and wrong:)

Great! At least they learned their lesson and integrated an extractor fan to create a certain air movement. This priciple was already used (in a more basic way) 40 years ago in the apartment towers in Central Europe. But the heating costs in those days have been just a friction in comparison to nowadays.
Who´s defining the "demand" to control such a ventilation? Beside the humidity and C02 level, there are other important criterias like VOC and radon as well. What happens if it ends in the result that you have a huge demand for controlled ventilation? The break-even-point could be closer than some people consider. Saving money when buying a ventilation system is great but just makes sense in case you do not loose even more money by operating the system afterwards.

bcoll05

I appreciate everyone's input & opinion.
I like the Demand Control as it's not constantly running. Alot of the systems are 24/7 no matter who or if anybody is at home to benefit from it.
Demand control. The extracts are ran from wet rooms (kitchen,bathrooms) through ducting & for me up to the attic & out through the roof.
The only run when a sensor detects somebody or humidity in the rooms. The inlets as said before in a previous post open when humidity is detected in the room.
So when nobody's home it's keeping your heat in & extracts it when needed.
That's my appeal to the system.

It would still be great to hear from someone that has it installed.

Wartburg

bcoll05 wrote: »

... It would still be great to hear from someone that has it installed.

Would love to hear some real & true experiences about DCV too.

BryanF

bcoll05 wrote: »

I appreciate everyone's input & opinion.
I like the Demand Control as it's not constantly running. Alot of the systems are 24/7 no matter who or if anybody is at home to benefit from it.
Demand control. The extracts are ran from wet rooms (kitchen,bathrooms) through ducting & for me up to the attic & out through the roof.
The only run when a sensor detects somebody or humidity in the rooms. The inlets as said before in a previous post open when humidity is detected in the room.
So when nobody's home it's keeping your heat in & extracts it when needed.
That's my appeal to the system.

It would still be great to hear from someone that has it installed.

Not true aeroco DCV extra t unit runs constantly. It’s just the intakes that open/close based on RH

bcoll05

BryanF your right. I should have explained that a bit better. Have you seen the system in use?

BryanF

bcoll05 wrote: »

BryanF your right. I should have explained that a bit better. Have you seen the system in use?

Yes I’ve specified the system

And considering it for my own house currently

Lumen

I got a quote for Aereco DCV but TBH most of the value to me is in quiet extract from two bathrooms which are directly under my attic, so I'm more likely to just fit a couple of 150mm inline fans in the attic vented through the gable end and use the existing kitchen hood extract and passive vents for demisting the kitchen. This is a fraction of the cost and most of the value in my (currently) leaky house.

verona21

Lumen wrote: »

I got a quote for Aereco DCV but TBH most of the value to me is in quiet extract from two bathrooms which are directly under my attic, so I'm more likely to just fit a couple of 150mm inline fans in the attic vented through the gable end and use the existing kitchen hood extract and passive vents for demisting the kitchen. This is a fraction of the cost and most of the value in my (currently) leaky house.

Hi,
How is your system working for you now? I'm leaning towards using the same setup in my house.

Muahahaha

Thinking of upgrading the ventilation in my own house and had looked into DCV. I'm no expert on it but my understanding is that in a retrofit it involves opening up walls/ceilings to run ducting back to a central fan and filter unit in the attic. Because of this it can work out quite expensive, the actual units themselves aren't all that dear but the cost of installing the ducting is.

I've wondered if it is possible to retrofit ventilation without using a ducting system. I know there are smart extractor fans on the market which turn on/off based on the temperature and relative humidity. I've yet to hear reviews of them but it would definitely work out cheaper to install stand alone units than running ducting all over the house.