No trickle vents

[rogmor]

If you install upvc double glazed replacement windows in the bay of a bedroom, does it need trickle vents? Cant find any threads on this but Building Regs mentions
'adequate background ventilation of a minimum 8,000 mm2 must be provided for all habitable rooms'.

Any info much appreciated.

 

[NickStone]

Trickle vents are designed to provide ventilation. If you don't have that ventilation, where are you going to get your fresh air? Where is the water-vapour produced by breathing to go? Double-glazing doesn't magically get rid of this water-vapour. It's still there and it has to go somewhere. If you want smelly carpets and mould in your wardrobes, dispensing with trickle vents is the best way to achieve it. But it's not just your decoration that will suffer. Stale air and high humidity is also bad for one's health and encourages house mites, so bad for asthma. (Sorry - but this is one of my hot buttons. My mother had double glazing put in without trickle vents and now her flat doesn't smell too good.) You'll find other threads on this forum started by people who have found the same thing happens.

 

[rogmor]

Thanks Nick, I completely agree, but I just needed to know if trickle vents are a Building Regs requirement. I had upvc windows installed without them and the room is now as you'd expect from lack of ventilation.

 

[NickStone]

Rogmor, I think it was in April 2006 that the regs changed. This is what Building Control told me at the time I complained about my mother's windows:
Replacement windows are required to comply with approved document L1B: Conservation of Fuel & Power. In addition replacement windows are also required to comply with Fire Safety and Ventilation requirements in that replacement windows should be no worse than the windows that are being replaced in terms of opening area and ventilation. If the original windows had background ventilation then so should the replacement windows.

I note that you're in Portugal. In this country (Britain) if an installer is a member of FENSA, it's FENSA's job to enforce the conditions. If not, then it's the responsibility of the householder to ensure that the conditions are met and the local Building Control officer to enforce them.

 

[Richard C]

Unless the work is part of a material change of use, you don't have to have trickle vents if there were none there before. Personally I didn’t have them fitted to the new windows that went in 2005; we have night latches which used to be regarded as an alternative but, in the latest regs amendment (2006), it seems no longer the case. The problem with trickle vents is they still have to be left open &, of course, people will close them to prevent draughts!

We have never had any problems with condensation, in this property (with new windows) or our previous property with original install D/G. The secret is not to live in a hermetically sealed environment! Always allow daily ventilation; we have the bedroom window open at night in all but the coldest of weather, always night latch a window & turn on the extractor fans when using the kitchen, utility & bathroom & never dry washing next to the radiators.

 

[Mw Roofline]

Thanks Nick, I completely agree, but I just needed to know if trickle vents are a Building Regs requirement. I had upvc windows installed without them and the room is now as you'd expect from lack of ventilation.

FENSA inspectors like you to have TV's in bathrooms/shower rooms, kitchens and utilities. In other words, anywhere that gets steamy. You don't have to have one on every window in the house unless its a new build.

 

[NickStone]

FENSA inspectors like you to have TV's in bathrooms/shower rooms, kitchens and utilities. In other words, anywhere that gets steamy. You don't have to have one on every window in the house unless its a new build.

According to my information from Building Control, you do if you're replacing a window that had a trickle vent. And you are also expected to ensure adequate ventilation wherever the window is installed. I quote from the regulations introduced in 2006:

"3.3 To comply with Requirement F1, all replacement windows should include trickle ventilators. Alternatively, an equivalent background ventilation opening should be provided in the same room. In all cases, the ventilation opening should not be smaller than was originally provided, and it should be controllable."

The easiest way to achieve this is with a trickle vent. Of course, there are other options of which ventilation bricks is one, whole-heat recovery systems another. The basic fact is though that anyone who thinks double glazing reduces condensation is mistaken. It removes it from windows but water vapour is water vapour and it must condense somewhere. If it's not on the windows, it's somewhere else, such as the fabric of the house of which black mould behind cupboards is one obvious example.

 

[Richard C]

FENSA inspectors like you to have TV's in bathrooms/shower rooms, kitchens and utilities. In other words, anywhere that gets steamy. You don't have to have one on every window in the house unless its a new build.

According to my information from Building Control, you do if you're replacing a window that had a trickle vent. And you are also expected to ensure adequate ventilation wherever the window is installed. I quote from the regulations introduced in 2006:

"3.3 To comply with Requirement F1, all replacement windows should include trickle ventilators. Alternatively, an equivalent background ventilation opening should be provided in the same room. In all cases, the ventilation opening should not be smaller than was originally provided, and it should be controllable."

The easiest way to achieve this is with a trickle vent. Of course, there are other options of which ventilation bricks is one, whole-heat recovery systems another. The basic fact is though that anyone who thinks double glazing reduces condensation is mistaken. It removes it from windows but water vapour is water vapour and it must condense somewhere. If it's not on the windows, it's somewhere else, such as the fabric of the house of which black mould behind cupboards is one obvious example.

You’ve mis-quoted section 3.3; the bit “trickle ventilators must be fitted” is in section 3.4! There is also an amendment to the 2006 edition you quote (see the gov website) which overrides the lot as follows:

Delete paragraph 3.4 and replace with the following:
“3.4. Where the original windows were fitted with trickle ventilators the replacement
windows should include them and they should be sized as set-out in paragraph
3.6. It would be good practice to fit trickle ventilators (or equivalent), with accessible
controls, in all replacement windows to help with control of condensation and improve indoor air quality”.

So as far as I can see, the requirement to fit trickle vents where thre was none fitted before has been superseded by amendment to an advisory note only; so you don’t have to fit them if they were not fitted before.

 

[freddiemercurystwin]

No disrespect to any forumites here but a minute long phone call to building control will answer this question without any shadow of a doubt. As they'll need to approve it it would make sense to let them decide.

 

[NickStone]

[quote="Richard C"

so you don’t have to fit them if they were not fitted before.[/quote]

Uh - yes, I believe that's what I said. But if you're sensible and you want to stay healthy and not have all the condensation that used to collect on single-glazed windows in your carpet, clothes, wardrobes and walls, you can't just seal up your windows and think it's OK. So, as you said yourself, you use extractors and leave your bedroom window open all night. This creates draught and lets out all the heat you've created during the day, which does beg the question of why you have dg in the first place. (I don't mean you personally. I mean people who think it's a good way to save money and the planet.)

 

[NickStone]

No disrespect to any forumites here but a minute long phone call to building control will answer this question without any shadow of a doubt. As they'll need to approve it it would make sense to let them decide.

Freddy, my info came from Cotswold District Council Building Control. Really, though, it's not so much about regulations or what supersedes what, but common sense. I was around in the seventies when double-glazing was big business with everyone rushing to put in these horrible things that sealed up their houses, made them smell, without doing any of the other things that would compensate for the extra moisture or stale air. The healthiest house I ever lived in was built in 1860, had fireplaces in every room, single-glazing and was quite frankly a bit draughty. But there was rarely any condensation on the windows and we hardly ever caught colds. In terms of resources, plain wooden windows will last a very long time if looked after. UPVC lasts between 15 and 25 years and its production methods are hardly green.

 

[freddiemercurystwin]

No disrespect to any forumites here but a minute long phone call to building control will answer this question without any shadow of a doubt. As they'll need to approve it it would make sense to let them decide.

Freddy, my info came from Cotswold District Council Building Control. Really, though, it's not so much about regulations or what supersedes what, but common sense. I was around in the seventies when double-glazing was big business with everyone rushing to put in these horrible things that sealed up their houses, made them smell, without doing any of the other things that would compensate for the extra moisture or stale air. The healthiest house I ever lived in was built in 1860, had fireplaces in every room, single-glazing and was quite frankly a bit draughty. But there was rarely any condensation on the windows and we hardly ever caught colds. In terms of resources, plain wooden windows will last a very long time if looked after. UPVC lasts between 15 and 25 years and its production methods are hardly green.

The OP needs to talk to his building control, as we know they vary all around the country, no disrespect but using the advice of your local building control hardly seems relative. If he contacts his own BC, they will say yes or no depending on his existing conditions, information the OP has not provide on here. Job done. If the OP's having the windows installed by a Fensa fitter and he contradicts BC then I agree its worth a debate. There is no definitive answer for this (and never will be), the need or not for trickle vents depends on a whole host of things, age of property, construction, condition, how the owner lives in their house, all sorts of things.

 

[Coniferman]

Isn't dg supposed to help warm the house up which will reduce the RELATIVE humidity thus reducing the ability of condensation to form??

 

[NickStone]

[quote="freddymercurystwin";p="747884[/quote]

Thanks for your insight, Freddie. I hadn't realised that building regulations varied throughout the country.

 

[NickStone]

Isn't dg supposed to help warm the house up which will reduce the RELATIVE humidity thus reducing the ability of condensation to form??

Useful article on this at: http://www.double-glazing-replacement-windows.co.uk/condensation.htm