Do you offer free quotes?⌄
Yes, quotes are free with no obligation. Call or WhatsApp and we can discuss the job - for anything straightforward I can usually give a price over the phone, and for larger jobs I'll arrange a site visit.
What is a PIV unit and how does it work?⌄
A Positive Input Ventilation (PIV) unit is installed in the loft and gently draws in fresh air from outside, conditions it slightly so it doesn't cool the house, and pushes it into the property at low pressure. This creates a small positive pressure that pushes moisture-laden air out through natural gaps — gaps that exist in every older property.
The key difference from an extractor fan is that it works on the whole house continuously, rather than pulling air out of one room intermittently. It's the most effective long-term solution for condensation damp in solid-wall or poorly-ventilated properties, and it's been the recommended approach for granite construction houses in West Cornwall for years.
What area do you cover?⌄
I cover Penzance, St Ives, Hayle, Marazion, Newlyn, St Just, Camborne, and the wider Penwith peninsula. If you're unsure whether you're in range, just call and ask - I'm happy to travel for the right job.
Will a PIV unit fix black mould?⌄
In most cases, yes — provided the mould is caused by condensation damp rather than penetrating damp or a structural water ingress problem. A PIV unit won't fix a leak behind a wall or rising damp through a floor.
If the mould is on cold external walls and ceilings — especially in corners, bedrooms, and bathrooms — that's almost always condensation. A PIV unit, once installed, typically produces clear results within a single winter. Existing mould can be treated and should not return once the moisture level in the property drops.
Are you NAPIT registered?⌄
Yes, I'm NAPIT registered - member number 66376. You can verify this on the NAPIT website by searching for Cornovii Electrical. NAPIT registration means I'm assessed annually against industry standards and can self-certify notifiable electrical work, including consumer unit upgrades and new circuits.
How much does PIV installation cost in Penwith?⌄
A supply-and-install price starts from around £450 for a straightforward installation — standard loft access, existing fire alarm circuit to wire the relay from, and a short duct run.
More complex jobs — small hatches, steep roof pitches, or properties where relay wiring is more involved — may cost a little more. I always confirm a fixed price after a site visit rather than quoting blind.
Are you VAT registered?⌄
Not currently, which means there's no VAT to add on top of my prices. This may change in the future, but any change would be communicated clearly before work is quoted or carried out.
Does a PIV unit need an electrician to install it?⌄
Yes. While the unit itself is relatively straightforward to position, the electrical connection and the relay wiring to the fire alarm circuit must be done by a registered electrician. The relay ensures the PIV shuts down on alarm activation — this is a safety requirement, not an optional extra, and it needs to be done correctly.
As a NAPIT-registered electrician I handle the full installation, including testing and certification. You won't need a separate visit from another trade.
