PIV (Positive input ventilation) systems are not allowed in many European countries
This is because they overcome the insulation added to the home such as double glazing and insulation, thus making the home less energy efficient overall.
Outside Cold Air Enters From the Loft
Air in the loft space enters from ventilation gaps in the roof to the outside.
This air is heated by the Home Heating
As cold air from the outside is forced into the home, it mixes with the warm air inside the home that is already humid.
This Heated Air Is Forced Outside
Warm, humid inside air is forced to the outside through gaps around the home: no home is air tight.
What is the CHEAP ENVIROVENT Alternative?
Excess moisture is trapped in the home causing dampness, mould and condensation; it’s a modern problem. The more we seal a home to keep in the heat, the more dampness is retained inside. Instead, the PIV system pressurizes the home, forcing air out through natural openings. No door or window is fully sealed and air can be forced through even the ceiling to the roof space.
DH1200 better alternative or just a cheap envirovent alternative?
The DH1200 can draw air from bedrooms or bathrooms, dry the air then put it back to any point. Excess moisture can be vented away to the outside.SEE THE DH1200
LD800 Allows fresh air in & keeps heat in. Includes HEPA filter.
For larger properties, take a look at the LD800: it takes fresh air from either the outside or air from the loft space, keeping the house both healthy and heat retained.See the LD800
So, here is the sales pitch for the PIV System:
PIV systems work as a whole house ventilation system and create a unique and healthy living environment by supplying fresh, filtered air into a property at a continuous rate throughout.
PIV is required when you:
✔ Don’t want to do a full renovation.
✔ Require a whole house ventilation solution.
✔ Don’t want to remove any walls or go back to brickwork.
But here’s the truth of what it is saying – PIV
PIV works as a whole house ventilation system, bypassing the expensive insulation that you would otherwise put in place.
This creates colder, gustier air in the home, which indeed feels fresher. Healthy environments do need fresh air but your home is actually designed for that anyway. The real issue is to take away the condensation but leave the heat in at a continuous regulated rate throughout depending on the humidity level.
PIV is required when you:
✔ Don’t care about heat or heating bills.
✔ Require a door to be left open when it’s operation but don’t want the security risk.
✔ Think that you need to remove all plaster back to the brickwork in the home to solve a condensation problem.