new windows. Trickle vents or not?

29 Aug 2006
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United Kingdom

I've got some new Double glazed windows being fitted in a couple of weeks time into my lounge and bedrooms.

I've initially opted for no trickle vents, the rationale being:

* lounge -> not used much, and has a chimney which provides ventilation
* bedrooms -> if we want ventilation, we can just lock the window in vented mode
* I live near a main road, and you can hear road noise through the trickle vents I have in another room. I would rather be able to shut that out when required.

I keep having doubts that I've done the wrong thing. My logic makes sense to me, but I wondered if anyone more experienced on here spots a big error in my thinking?
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Optional really.

The approved documents are worded so as to say you ‘should’ have them, but not necessarily ‘must’ have them.

Living near a road I would also go without them due to noise, and choose when to open my windows on the latch.
Lawfully you only need them in new windows if the windows they replace have them, despite what any fitters or window suppliers may tell you.
thanks for the confirmation. I was happy with my decision, and then the doubt started to creep in...
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They can always be retro fitted if required.

Personally I dislike them and wouldn't have them:
Always dirty and hard to clean
Let bugs in
And finally you pay lots of money for thermally efficient windows then go and drill a massive hole through them.
Windows would no longer pass their A, B and C ratings with trickle vents fitted. Technically they should make the window against regulation to fit but its another set of regs that forces us to fit them lol
Lawfully you only need them in new windows if the windows they replace have them, despite what any fitters or window suppliers may tell you.

Hate to say ..the rules actually state that if you an open fire/gas appliance/oil burner and NO air bricks, then you must fit trickle vents for background ventilaton. Both Fensa and Certass ( and building control should too ) will fail any installation that has an open fireplace , with no airbrick ( or floor vent ) and no trickle vents in the window. It is to stop the potential build up of Carbon Monoxide gas within the room.

I am not saying for one minute I think Trickle vents are nice but they are there for a reason.
I think if your windows have opening vents you might be alright but not if you have a fireplace.

Had similar problem myself. I replaced a window without trickle vents with a sliding patio door without trickle vents. I had radiators in the room and a plastered up chimney breast with a low level vent. Building Control Officer came to inspect and said I needed to put in an air brick/vent at head height on the exterior wall as I had no means of ventilation. I read through all the regulations and realised he was right so duly punched a hole through the wall, fitted a vent and contacted them again - a different BCO said he thought the other BCO, although technically correct, had been a big strict and he would have okayed it without the vent. Still none the wiser...
i dont see the point in them to be honest. as long as you have all the appropriate air bricks etc as mentioned above do without. flimsy things anyway :LOL:
I'm in a similar situation - just about to order some new double glazing, but not sure if I should include slot trickle vents in each window. My thoughts are:
- They are not a mandatory requirement of building regs, which suggests they aren't really needed
- They break up the frame of the window and look untidy
- Our existing softwood windows do have trickle vents, some are open, but most are closed, so there doesn't seem to be a reason to have them (our house is 17 years old)
- Having them open defeats the point of having good quality sealed windows, from an energy usage point of view as I assume they allow cold air in

Despite all the negatives, I'm concerned if I don't have them, I don't have the flexibility to ventilate individual rooms should that become necessary (without having to open windows).

Like the original poster, my thought was to do without (and save some money), but now I'm having second thoughts!
I think you said you currently have trickle vents? In which case you may have no option.
If you have them they "must be" replaced.

Personally if it was my house and I was fitting them myself I wouldn't but you may struggle to find a company thats willing to supply and/or fit them without the vents.
you may struggle to find a company thats willing to supply and/or fit them without the vents.

The company supplying the new aluminium double glazing has quoted without the trickle vents and has listed them as an option (at a cost of £23.70 incl VAT per window), so they aren't forcing us to have them.

Where does it say in the building regs that if windows with trickle vents are being replaced, the replacements must also have trickle vents? I would be interested to understand the justification of the building regs enforcing the continued use of trickle vents, but not enforcing the blanket use of them. It seems to me that some of the building regs just don't make sense, and this is up there with the "minimum U values for new external doors". How on earth do they ever enforce some of these rules?
Is that company supplying only?
Who will be fitting and who will be signing them off? Its the person signing them off that you may need to worry about.
If someone is FENSAing them its unlikely they would be caught out but if they did it could end up costing them about £1000 in extra inspection fees.

Its all in document F somewhere.
Basically its because new homes are too well insulated and sealed. Without ventilation it would lead to old unhealthy air in the house.
If only someone could invent a way to open a window?
The same company is supplying and fitting the windows and they are FENSA registered!

I've just had a quick look at the 2010 building regulations for Part F (Ventilation) and I'm struggling to find anything that states that like for like ventilated windows must be fitted. Also, there has been no mention of getting the new windows signed off, so I have assumed planning isn't required!
Its in there somewhere in legal jargon.

If they are FENSA registered they will be self certifying the job with building control.
Planning should only be required if you are in a conservation area or listed building (possibly flats too).

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