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Comments
The net result is that most of our neighbours keep them closed & my wife continually complains that I leave them open. Perhaps I'm more sensitive to air quality than most people, but it doesn't seem right to close the only source of deliberate ventilation.
David
Most of us (maybe a few woodburning 'good-lifers may disagree) would like a home that is fully automatic and senses our every needs, tall order you may think, but if we took a leaf out of the automotive industry we could easily achieve it.
My 10 year old Renault Scenic has electric windows (could easily be changed to open and close on their own), air conditioning that works well, as does the heater, combining the two and cabin temperature and air quality is very good. The air is also filtered, de-humidified and distributed well, adjustable too, but I tend to keep it on feet and screen and 'No 2' on the fan.
Under the bonnet, there is an engine management system that senses the air temperature, density and pressure and automatically adjusts the the fuel injection for the vehicle speed, engine load and fuel quality (it can 'hear' pre-detonation and if it was the gasoline version would adjust even more settings). There are also labour saving devices such as power steering and power braking (with anti-locking), door open sense, seat belt sensors, air-bags, easy to understand display, a radio that knows where I am and keeps me tuned into Radio 4, and a CD player for those 'Dylan Moments'.
All these feature can be had on a car costing less than £10,000. People on here talk about buying windows and wood burners/thermal stores at that sort of money.
I can remember when a PC costs about £2500, but more can be had now for under £100. In the mid 80's I did a computer course and we used a Z80 to learn how to write code in assembly language, even that simple, cheap, low power processor could handle 254 inputs/outputs, and we think that TVR's and separate room thermostats coupled to a modulating gas boiler is 'pretty neat'.
New post for you Tony, 'Why do we put up with such rubbish in our homes'
After 20 minutes thinking about the I may have worked out why we put up with it, domestic gas, electric, oil, coal and timber are way too cheap.
Because we british are conservative with regard to buildings , not generally keen on any sort of change.
Most client like to see thing they're used to . it makes them feel secure.
Trademen make a living doing it the way they know, new stuff creates a risk to thier potential income.
With a bit of discussion building inspectors will accept an opening lockable vent on the window as sufficient background ventilation to comply with regs. thus doing away with trickle vents.
So as a group (British Home Owners) we cannot really complain about our utility bills, some of the cheapest in the EU.
What i personnally like about building, is thier's alway new stuff to learn and experiment with.
Thing is, Jeremy, it never used to be!
The question (that has spontaneously appeared in a thread that was quite specific in its subject) needs turning on its head: "Why should we need to save energy that we shouldn't be using so much of in the first place?"
As for trickle vents, they weren't intended just for ventilation to keep condensation down, they were intended to get a supply of fresh air to whatever means of combustible material you were burning to keep warm. In one instance I had a BCO who insisted that I fit permanently-open trickle vents because there was a coal fire in the room, and that was a concession in place of an air brick, new draught-proofed doors having been fitted.
In that situation the only alternative is MHVR on whatever scale.
In terms of condensation, the crazy thing was that vents were only mandated in 'habitable' rooms, ignoring the rooms where condensation was most likely to occur! :confused:
Oh, and things were eventually relaxed on replacement windows, when if trickle vents hadn't been fitted originally they didn't have to be fitted on the new windows if night-vent catches were fitted. So someone eventually woke up to the stupidity of making a higher performance window and then putting bloody great holes in it.
It seems that windows were chosen as a means to do this, not because that was the logical thing to do (who in their right mind buys a nicely sealed, well-insulated, new window and insists in drilling holes through it?) but because it was a practical way of addressing the potential problem that retrofitting new windows to an existing house might cause. The gross stupidity was to apply the same logic (the insistence on having trickle vents) to new build houses, where far more effective and efficient ventilation methods could be designed in.
Over the years that I've been improving my current house (in terms of reducing energy usage) I've created some significant problems that a properly designed whole house ventilation scheme could have avoided. For example, when I increased the insulation in the loft, I created vast amounts of condensation on the sarking, which then drips down and forms pools, eventually soaking through the ceiling (which is how I found out about it). The roof space is ventilated at the gables, but not enough to deal with the problem, so new soffit vents had to be fitted. When I replaced all the windows and doors with new, far more thermally efficient, ones (the old ones were 1980's standard DG that used to attract condensation) I created a condensation problem on the north wall internally, which manifested itself as black mould growing behind furniture. The fix for that was to move the furniture away from that wall and fit cavity wall insulation, to get the internal wall temperature above the dew point. The consequence of fitting cavity wall insulation has been that the windows are now the best condensing surfaces once again................
Having been through this learning process, I'm now quite clear about what I need to do in the new build. I also know full well just how much of a nuisance, and how ineffective, trickle vents are.
When we built the extension we asked the BCO to accept lockable night vents (window opening a little and being able to be locked) as trickle vents and pointed out that other local councils would accept this method of trickle vents) but he insisted that trickle vents be fitted to the new double glazed windows, so we fitted them but we didnt cut a hole in the window frame and he went away happy.
essentially all they were doing was creating a highly conductive cold bridge to the outside air, which with minus 15 type winter air temperatures, was just wicking heat out of the house, and causing huge condensation problems on the windows as the water would condense on the trickle vents and then run down the windows.
they never had them open anyway and had no need of them as it's a huge bungalow with MHRV in the bathroom and drying room, and the ceiling and walls are vapour permiable with lots of ventilation to the loft. Air tightness wasn't likely to be particularly high either.
The metal temperature on the inside rose from about -10 to about 8 degrees immediately after doing this, and the next morning the window sills weren't dripping wet as they had been every other morning.
I agree - trickle vents, particularly metal ones are total madness.
eta - and their oil boiler is in the garage and always has been, so there's no excuse there.
The front of the house straight into SW gales and the draught though the vents was far from a trickle even when firmly closed. We'd also discovered by then that they didn't really need to have been there in the first place.
Our solution was to remove the fittings (a shaded grill on the outside, & a flap on the inside), then working from each side use just enough silicone to replace the "skin" in each face of the frame where the slot had been routed out, then replace the fittings. It now looks as though we have trickle vents, but there's no point in trying to open them - and no draught through them. If we want extra ventilation we have opening windows, with night latches...
So I think trickle vents aren't insistent stupidity by regulators, they're corporate greed and rigidity of opinion of mass market builders.
Do you mean because it's the cheapest way to make a big-enough hole in new-build?
The downside was the large amount of fuel needed to heat homes like this, which ultimately ended up with big cities, like London, becoming renowned for thick fog that killed thousands every winter.
¹ I think that was the number around 1910 or so.
I also own flats built in 1965, with uPVC windows fitted in 2005. I had trickle vents fitted and just as well, as some of the flats can get quite fetid and damp from condensation. I made sure that the inside cover directs the air upwards to avoid draughts, and so that the open vent is not visible; the windows arrived with the vents all facing down, so I reversed them. Mostly tenants leave them open; I doubt if they would if the vents faced down. I was interested to note from another thread that cavity wall insulation (which the block has) can substantially reduce air movement through walls. Two owner occupied flats in the block do not have trickle vents in their DG windows and one regularly has condensation on her DG windows. There are no open flued appliances in our house nor in the flats (I removed gas fires as I bought each flat- each has a room-sealed CH boiler).
The windows all have "secure ventilation" latch positions, but to my mind they allow much too much ventilation for normal winter use, hence the appeal of trickle vents.
The ideal would be vents (in ceiling) which open and close on a (horse hair) humidity sensor.
Obviously if you have MHRV you should not have vents.
An easy alternative to trickle vents is to simply cut out some of the rubber gasket which modern windows have. I cut it out at the bottom of opening top lights, so the incoming ventilation is high and rising. Obviously these "vents" cannot be closed, except by reinserting the piece of gasket, so start with a small piece, and enlarge if necessary. Remember to cut outer as well as inner gasket.
One thing which bugs me about trickle vents is that they destroy the separation of the chambers, which must greatly increase the heat loss through the frame. So on some of the windows I took off the inside cover of the trickle vents and squirted expanding foam into the chambers either side of the trickle vent area to reinstate the separation of the chambers. This could very easily be done at the factory, or they could go the whole hog and fill the whole frame with foam.
OR in some rooms I have made separate vents in the wall, which can be adjusted between closed and open; they are too narrow for a thief to get through, but about a square foot in area so good fully open for overnight ventilation in summer, as well as for trickle ventilation.
Not until a brave government taxes the hell out of domestic fuel will people see the need to reduce their consumption. The tax raised would pay for the 90% of UK housing stock that doesn’t even meet Building Regs U-values to get some proper insulation, double glazing and draught proofing.
Controversially, I use coal (as well as wood) to heat my house. I burn it at 75% efficiency in my stove. The coal power stations struggle to achieve 40% efficiency creating electricity then everybody with a heatpump tells us how green their installation is cos they make no NOX,SOX and CO. It’s all wrong. When will the world wake up to reality?