Positive Input Ventilation Advice

Ben1989

Hi all,

Some condensation issues in the house. Really been grabbed by installed a PIV unit to help improve it. 

One reason for condensation is the front box room getting cold. I've heard of the PIV's making the upstairs chilly with the heater elements doing next to nothing to improve it. Is this the case? I have a 1930s semi where there tends to be no radiators on the landing. 

Also, Vent Axia seem to be cheaper than others yet others have tended to go with Nuaire. Is there a particular reason for this?

TIA

Doozergirl

What condensation issues? Where? 

Ben1989

Downstairs hallway, in the upstairs toilet (separate room to bathroom), front box room.

Also, my daughter has eczema and minor allergy issues I'd like the benefit of.

FreeBear

Ben1989 said: One reason for condensation is the front box room getting cold....  I have a 1930s semi where there tends to be no radiators on the landing.

Solid brick walls on the upper half of the property ?

Similar aged property here, and there wouldn't be anywhere to hang a radiator on the landing that wouldn't encroach on a doorway. Also suffered from condensation in the box room, in part, due to a lack of heating in there. My solution was to strip the walls & ceiling, and insulate as much as I could. With just a small 600x500mm type 21 radiator in there, the room is nice and cosy. Still get a little bit of condensation on the window if the door is kept closed all day/night with an occupant..

Ben1989

Yes solid walls. Cavity walls which are non-insulated. We have a corner window in the box room. Literally a window which has two sides which are 90°. That lets cold air in as they're probably 20 years old. Also there is a vent in there which I'm torn whether to take out or not.

Yes I will be stripping the plaster off to brick and using insulating plasterboard (is this what you used?). I will be opting for a vertical T21 to save space as the plasterboard will encroach on the already small space.

FreeBear

Ben1989 said: Yes I will be stripping the plaster off to brick and using insulating plasterboard (is this what you used?). I will be opting for a vertical T21 to save space as the plasterboard will encroach on the already small space.

I used multiple layers of 25mm Celotex & warm battens. Also insulated around the window reveals for good measure.

The vent is going to be a major source of cold - Get that bricked up as soon as you can.

Ben1989

Did you also have a PIV unit?

FreeBear

Ben1989 said: Did you also have a PIV unit?

Haven't felt the need for a PIV or any other ventilation system. Have an extractor in the kitchen, but not the bathroom (yet). Also refuse to have trickle vents on any windows.

Ben1989

Anybody else have experience with a PIV?

Gers

Yes, I had one installed recently, it's very good.  A Nuaire model without the heating element or hall control.  There is a slight feeling of cool air coming out of the unit in the ceiling and an even more slight noise from it when close to it, however neither are intrusive or worrying.

Since it's been installed my very old stone cottage is much less cold and the condensation is gone.  I don't have heating upstairs and only use the wood burner downstairs, the whole place feels much more comfortable.  An electrician came to put in a new feed to the loft and a handy neighbour cut the hole and fixed the bracket in the loft - I don't know much more than that as I stayed away on the grounds of being useless!

Based on my own experience I'd recommend one.

Ben1989

Thank you. May I ask how it feels less cold when it's pulling air from outside (indirectly)?