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    • CommentAuthortony
    • CommentTimeNov 11th 2011
     
    It would seem that the vast majority of trickle vents are kept closed all the time

    They are therefore a waste of time and money and hence the opposite to sustainable - antisustainable!

    Whose idea were they and why are we still using them , many of the homes they are in have more draughts through air leakage paths than the tv's offer even new houses.
  1.  
    We live in a commercially built new house & I am continuously adjusting the trickle vents to ensure good air quality without draughts. However, any change in the wind or outside air temperature leads to some of the rooms feeling colder than others & generally cold draughts across the floor. On cold nights it is very uncomfotable to be anywhere near a window.

    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
    •  
      CommentAuthornigel
    • CommentTimeNov 11th 2011
     
    they are a regulation draught
    •  
      CommentAuthorSteamyTea
    • CommentTimeNov 13th 2011 edited
     
    Does seem interesting that we think of a design feature like a trickle vent as 'automatic', it is only a hole in the wall after all.
    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.
    • CommentAuthorjamesingram
    • CommentTimeNov 13th 2011 edited
     
    'Why do we put up with such rubbish in our homes'
    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.
    •  
      CommentAuthorSteamyTea
    • CommentTimeNov 13th 2011 edited
     
    I tend to agree with you there James.
    So as a group (British Home Owners) we cannot really complain about our utility bills, some of the cheapest in the EU.
    •  
      CommentAuthorJSHarris
    • CommentTimeNov 13th 2011
     
    <blockquote><cite>Posted By: jamesingram</cite>Trademen make a living doing it the way they know, new stuff creates a risk to thier potential income.</blockquote>

    There's a great deal of truth in that statement. I've been hunting around for a builder to build my new house for a while now, and the vast majority very clearly feel uncomfortable about my obsession with insulation levels, absence of cold bridges and air tightness. One even had the audacity to tell me not to worry about all that stuff, as he'd been building houses for years and it just wasn't necessary...........
    • CommentAuthorjamesingram
    • CommentTimeNov 13th 2011 edited
     
    JSH , Never build a whole house myself , just bits of them . If you're anywhere near Slough , I'd be happy to give it go at your expense :bigsmile:
    What i personnally like about building, is thier's alway new stuff to learn and experiment with.
    • CommentAuthorJoiner
    • CommentTimeNov 13th 2011 edited
     
    "One even had the audacity to tell me not to worry about all that stuff, as he'd been building houses for years and it just wasn't necessary"

    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.
    •  
      CommentAuthorSteamyTea
    • CommentTimeNov 13th 2011
     
    Posted By: JSHarrisOne even had the audacity to tell me not to worry about all that stuff, as he'd been building houses for years and it just wasn't necessary...........


    Then make a deal with him that you will pay him based on kWh saved, use his existing builds as the baseline (he will know these figures judging by his statement above), you may end up with a cheap house.
    •  
      CommentAuthorJSHarris
    • CommentTimeNov 13th 2011
     
    The whole subject of ventilation in houses is something that seems to have been approached from a very unscientific way, in terms of the regulations. I can understand how, as people wanted more comfortable and less draughty homes, the powers that be became concerned about ensuring adequate supplies of fresh air, both for any combustible fuel appliances and the occupants.

    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.
    •  
      CommentAuthorjoe90
    • CommentTimeNov 13th 2011
     
    When a friend of mine bought a 1950's bungalow the mortgage company stipulated that he fit vent holes in all the soffit boards to ventilate the loft space, it was only when I build an extension some years later I discovered the walls were built up tight to, even mortored to, the roofing felt so the soffit vents did nothing for the loft ventilation.

    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.
    • CommentAuthorGavin_A
    • CommentTimeNov 13th 2011 edited
     
    first thing I did on my aunties house up in inverness / black isle when looking at her energy saving / condensation issues was to remove the metal trickle vents from the windows, stuff them with sheeps wool insulation and put them back on again.

    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.
    • CommentAuthortony
    • CommentTimeNov 13th 2011
     
    so not just antisustainable but worse than that -- a complete nonsense and costing money to rectify
    • CommentAuthorskyewright
    • CommentTimeNov 13th 2011 edited
     
    Posted By: jamesingramTrademen make a living doing it the way they know, new stuff creates a risk to thier potential income.

    Posted By: Joinereventually 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.

    Posted By: joe90so we fitted them but we didnt cut a hole in the window frame

    We sort of combine all 3 of those. Some D/G replacement windows had trickle vents. Q: Why? A: 'Cos that's what we always do. It's the regs...
    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...
    • CommentAuthordjh
    • CommentTimeNov 14th 2011
     
    Posted By: JSHarrisThe 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.

    AFAIK, the regs aren't stupid in that way. It's perfectly acceptable to drill a hole through the wall to provide the same ventilation area. I have a friend whose flat is built that way. (It's a lot easier to block up a 6" circular hole :bigsmile: )

    So I think trickle vents aren't insistent stupidity by regulators, they're corporate greed and rigidity of opinion of mass market builders.
    • CommentAuthorwookey
    • CommentTimeNov 14th 2011
     
    Why does corporate greed favour trickle vents?

    Do you mean because it's the cheapest way to make a big-enough hole in new-build?
    •  
      CommentAuthorSteamyTea
    • CommentTimeNov 14th 2011
     
    Posted By: wookeyDo you mean because it's the cheapest way to make a big-enough hole in new-build?


    Probably the profitable way rather than the cheapest
    • CommentAuthorJoiner
    • CommentTimeNov 15th 2011
     
    Back in the mid-80s I works-managed a very big replacement window factory producing many hundred of windows a week for large local authority consortium contracts all over the UK, but mainly London and its tower blocks. Aluminium was still the main material back then, upvc rapidly catching up (we opened up a new factory to cope with the increasing demand). I had the impression that trickle vents came in because the upvc industry (in fact the replacement window industry generally) were fitting cheap handles without night-vent provision. But that situation was no different to what was there originally, it was just perceived as a bad thing because someone had the bright idea that the effects of dampness in the housing stock could be mitigated by better ventilation, with the bonus that health could also be improved. Night-vented handles had always been an option, but one that had to be specified and paid for. The obvious simple solution of making night-vent handles mandatory seemed to pass the regulatory authorities by - probably because they didn't know they existed as an option, having visited only properties with cheap handles fitted when they did their "research"!
    •  
      CommentAuthorfostertom
    • CommentTimeNov 15th 2011
     
    This is a live Q right now - imminently hoping Bldg Insp will overlook the (recently tightened) rigidity of the Regs wording and accept night vent latching instead. They look like being v flexible about other things, so here's hoping. We need some case law and precedents to quote!
    • CommentAuthordjh
    • CommentTimeNov 15th 2011
     
    Posted By: wookeyWhy does corporate greed favour trickle vents?

    Do you mean because it's the cheapest way to make a big-enough hole in new-build?

    Well, it's easiest. The holes arrive pre-installed in the window. Drilling holes in walls and then capping them probably involves two trades and the possibility of all kinds of ghastly mistake. And windows can probably be made cheapest at least in a paper analysis if they aren't in reality.

    Posted By: fostertomoverlook the (recently tightened) rigidity of the Regs wording and accept night vent latching instead

    What are the current regs? Is there some perceived issue about the security of night latches?
    • CommentAuthorStuartB
    • CommentTimeNov 15th 2011
     
    How did the Victorians manage their ventilation and condensation issues? They normally had a simple effective solution.
    •  
      CommentAuthorJSHarris
    • CommentTimeNov 15th 2011
     
    <blockquote><cite>Posted By: StuartB</cite>How did the Victorians manage their ventilation and condensation issues? They normally had a simple effective solution.</blockquote>

    The simple answer is that they didn't need to. Their houses leaked like sieves, through the window and door frames and pretty much everywhere else, plus they used open fires in several rooms of a house, giving fairly effective ventilation.

    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.
    • CommentAuthortony
    • CommentTimeNov 15th 2011
     
    Smog I think we called it
    • CommentAuthorEd Davies
    • CommentTimeNov 15th 2011
     
    Not to mention the 1000 miners a year¹ who died digging the coal to heat the houses (and lots of other uses, of course).

    ¹ I think that was the number around 1910 or so.
    • CommentAuthormartin.n
    • CommentTimeNov 24th 2011 edited
     
    Whether you need trickle vents depends on how leaky your home is and how steamy the occupants are. Jane and I are post steamy, and our over-sized 1903 house, even after quite a bit of draughtstripping, is leaky enough to dry clothes in the hall and stairwell, so we don't need trickle vents there. A few replacement windows have trickle vents, at my specification, but nowadays I keep them shut, EXCEPT in the bedroom where condensation can be a problem. We have extract fans in kitchen and bathrooms.
    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.
    • CommentAuthormartin.n
    • CommentTimeNov 24th 2011
     
    uPVC window frames usually have two or more chambers, so they are the plastic equivalent of triple glazing.
    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.
    • CommentAuthormartin.n
    • CommentTimeNov 25th 2011 edited
     
    OR if window manufacturers fitted more than one night vent positions: e.g. one barely open (equivalent to trickle vent) and another as wide as remains thief resistant- with possibly a third intermediate position.
    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.
  2.  
    Steamy Tea, you are correct. Fuel is way too cheap. In my world it would all be different!...
    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?
    • CommentAuthorwookey
    • CommentTimeNov 28th 2011
     
    If the heat-pump user keeps their COP above 2 then they are more efficient being suppied by a 40%-efficient power stattion than your 75%-efficient stove burning coal locally. COP of 2 is not hard to achieve.
   
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