Lofty whole home ventilation system - any good?

[BA]

Hi
Need urgent reply.
Two bedroom end terraced house.
I had a survey done by enviro vent rep recently. He has quoted me £2400 for having a lofty unit and further there self run extractor fan one in the kitchen and the other two in the bathroom and shower room( supply and fitted) I felt it is over priced.. Or let's say he quoted me too much. Can anyone tell me how much should it cost? Is this quote a reasonable one?
I was told the running cost is just under £15.00 year for those all four units?

 

[ClockPie]

Hi

Hope this post is not considered spam, if so I'm sure the mods will delete it.

Anyway, I used this thread as part of my research, and ultimately I opted for a Nuaire Drimaster Heat. Surprisingly lol, it worked and continues to work well. Of course, every house is different, but for us at least - problem solved (with other things too).

I blogged about it on my travel blog, and the interest on the article was huge and wasn't really the right home for it, so whilst bored watching xmas movie repeats, I set up a quick website dedicated to PIV with as much information as I can muster up. The site is fully open and honest, so if you are researching, perhaps there are some valid tips there too

 

[theprinceofdarkness]

Just trying to make some comments on these systems. The open the windows brigade are sort of right, but are also sort of wrong. If your bedroom is hot, opening the window will only let the hot damp air out, if the hot air can be replaced by air from somewhere else. Even if its windy out side, unless there is a way in for air there will be no continuous flow of air out. What you will get is a bubble of cold air at the window as the room gets pressurised, with a mixture of hot and wet and cold and dry around the edge of the bubble. When the wind subsides, the pressurised bubble now "breaths out" and the bubble disappears. So what you are left with is a small convection current of the room's hot air drifting out of the top half of the window with outside air drifting in through the bottom half. How you are meant to get the cold air to vent the other side of the room is a mystery!
The same arguments equally apply for trickle ventilators.
The 1930/40/50s high level bedroom air bricks don't work either for the same reason.
What would work is a high level vent on one wall and a low level air intake on an opposite wall. Now you will get a continuous flow between them.
Using a fan to pressurise the whole house will cause a flow from its outlets to any air vents, cracks, badly fitting door windows etc. And its controllable to some degree. The air outlets (because the air will be cold/cool) will cause some degree of local convection currents in the rooms associated with the vents. Opening a window now will de-pressurise the house so only the outlet nearest the open window will be expelling air. In winter when the system is most needed I doubt if this would happen often.
So whats the score then?
2/10 for open windows
8/10 for pressurised air system.
9/10 for a "proper" heat recovery system *
* Its just that the ones I have researched for domestic use, do not quote for real and latent heat performances and also how they work with a 25 MPH wind (if at all)
Frank

 

[Carl1955]

Hi All

We have a 1 bed ground floor flat we rent out, the tenants have been in for around 4 years so seem to like the place but have recently (last few months)
complained to our letting agent about damp/condensation. there are some vents in the kitchen/bedroom and in the windows in the bathroom but doubt weather they have them open in winter or the doors in the flat so not much air gets circulated.
Our letting agent has contacted envirovent who've have done a survey and suggested

E-WALL Mr Venty ECO2 Wall mounted unit with heater for properties without a loft includes one external core hole
Fitted including VAT = £886.80
Also
CYC-SELV - Cyclone 12v Centrifugal, low
energy, re-cyclable extract fan with central
cartridge
Fitted including VAT = £366.00
Plus a white fixed louvre grill £4.80 inc VAT

Total price for job including fitting & VAT = £1,257.60

What do you guys think?, would these items cure the problem and is the quote a reasonable price

Thanks in advance

Carl.

[/b]

 

[JohnD]

if your tenants don't like ventilation, how will you prevent them turning it off?

 

[SimonH2]

E-WALL Mr Venty ECO2 Wall mounted unit with heater for properties without a loft includes one external core hole
Fitted including VAT = £886.80

It's a fan and a heater. At that price, a rather expensive one. If it were a heat-exchanger system like the K-Air ones my brother has fitted, then the price could be justified (it's around £450-£500 with VAT). Plus there'd be no excuse for the tenant to turn them off - the running costs are so low.

But as JohnD points out, if a tenant is penny pinching you can expect them to switch off something that costs money to run.

CYC-SELV - Cyclone 12v Centrifugal, low
energy, re-cyclable extract fan with central
cartridge
Fitted including VAT = £366.00

Again, I can't see what the high cost buys you over a sub-£50 fan.

 

[AronSearle]

there are some vents in the kitchen/bedroom and in the windows in the bathroom

Vents in the windows?

Or windows in the bathroom?

Either way get a proper extraction, I wouldn't be opening windows in winter. And vents in a window makes me think of those rubbish single glazing windows you only ever see in run down pub toilets.

Also consider upgrading the insulation as well where the condensation is worst.

 

[dryhomes]

I have recommended 100's of clients to install Drimasters when I worked for Dampco Ltd in South Devon.
The best results seemed to be using the Drimaster Heat but the standard model also works well.
Dryhomes are currently the cheapest supplier. (Feb 2015)
You can buy them for £300 including VAT and it will take an electrician a morning to fit one
Every home should have one - especially if they have draught proofing/insulation and double glazing.
Best wishes
Steve Linley-Shaw - a damp surveyor for 30 years

PS Envirovent do a similar PIV but want to fit them as well for about £800. Good if you are not handy or cannot find an electrician.
Permaguard sell them cheaper but add VAT