What rooms should ventilation vents be placed in?

B

brokeagain

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We are in the process of buying a house and engineer has pointed out that there are no vents in the house. The owner has asked what rooms we want the vents placed. Where are vents compulsory according to building regulations??
 
Maybe an opportunity to install HRV (Heat Recovery Ventilation) - depending upon how 'airtight' the house actually is...? Otherwise, maybe window trickle vents can be used instead?

I'm open to correction - but I would imagine it's all bedrooms and wetrooms that require ventilation.
 
LiveForTheWE said:
We are in the process of buying a house and engineer has pointed out that there are no vents in the house. The owner has asked what rooms we want the vents placed. Where are vents compulsory according to building regulations??
Click to expand...
look here http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1647,en.pdf

every room!
 
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If its 2nd hand built in the boom house I would wager it not being the most air tight so mechanical Heat recovery ventilation would not be the best.
Correct me if i'm wrong but the buidling regs are moving/have moved towards having no vents in the house to improve energy performance. An older house would natuarlly breath (i.e. leak) so you get natural ventilation.
I wuoldnt agree with this view and think ventilation should be in all habitable rooms. Mechanical vents in wet rooms (bath, ensuite, kitchen). I would go with wall vents in all rooms that you can close if its very windy. Another option, which my builder recommended for our house was to put the vents in the bedrooms upstairs in the ceiling and out out through the soffit. So we get no gusts coming in and the stale air still gets out.
As far as I've read/heard the window vents can have a negative affect on the U-value of your window.
 
LiveForTheWE said:
We are in the process of buying a house and engineer has pointed out that there are no vents in the house. The owner has asked what rooms we want the vents placed. Where are vents compulsory according to building regulations??
Click to expand...

Hi


You appear to already have an engineer appointed - you should ask him first.
If he says he is only competent to interpret and comment on Part A, appoint a competent architect and ask him to comment.
In general each habitable room requires ventilation, but you need a comment from the person you retain who is inspecting the house

Not all houses need permanent ventilation depending on their age and whether or not an MVHR system is used.
If the house is not built to the latest sealing standards and also using MVHR, it should have permavents.

If it has a gas appliance it will need a supply of fresh air and an exhaust or a local vent/extractor.
A litre of gas produces a litre of water vapour which can build up all too easily

Open fireplaces in older properties are deemed to be sufficient to vent the room the fireplace is in.
However it was assumed that supply air for this fire is through infiltration movement within the house.
When the fire is out and the chimney is not built-in or blocked or sealed, it acts as a vent

Depending on the age of the house different regulations will apply.
These regulations have changed several times over the past twenty years.
If the work was commenced before 1st June 1992 Building Bye-Laws may apply.

NOTE: Attempts to seal older houses while not supplying vented air can be a serious risk to occupants.


ONQ

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
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CBGB said:
If its 2nd hand built in the boom house I would wager it not being the most air tight so mechanical Heat recovery ventilation would not be the best.
Click to expand...
yes, not without improvements.
CBGB said:
Correct me if i'm wrong but the buidling regs are moving/have moved towards having no vents in the house to improve energy performance.
Click to expand...
wrong, vents are still required althought for the first tmie air-tightness (uncontrolled air-leakage) has been reduced slightly
CBGB said:
An older house would natuarlly breath (i.e. leak) so you get natural ventilation.
Click to expand...
i would suggest that the 'building breathing' and airleakage are to differnt things but i see where your coming from and this is a major problem where people upgrade there windows (for example) and don't consider including adequate ventilation
CBGB said:
Another option, which my builder recommended for our house was to put the vents in the bedrooms upstairs in the ceiling and out out through the soffit. So we get no gusts coming in and the stale air still gets out.
Click to expand...
this sounds a bit dodgy, ill have to check the Regs on that one..

CBGB said:
As far as I've read/heard the window vents can have a negative affect on the U-value of your window.
Click to expand...
not to my knowledge, the two (heat loss and ventilation) are taking as separate things entirely. theer maybe some arguemetn that the actual vent is not sophisticated enough to incorporate a thermal break etc. but I've yet to see a window unit U-value effected by regulation required permanent ventilation.
 
Thanks for your very informative reply. The house was built in 2005 but has never been lived in so we will be the first occupants. We are getting trickle vents installed in all windows now. I would be too worried about CO2 not to have some form of ventilation.
 
HI

Trickle vents in windows may have been acceptable under TGD F 2002.
As against this they can fail to function well if sealed off behind heavy drapes.

This is http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,22447,en.pdf (Technical Guidance Document F 2002), which would probably be the standard required at the time.
If you would like to review the changes that have occurred in recent years, here is http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1647,en.pdf (Technical Guidance Document F 2009).


ONQ

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
CBGB said:
Another option, which my builder recommended for our house was to put the vents in the bedrooms upstairs in the ceiling and out out through the soffit.
Click to expand...

Hi CBGB,

This isn't generally recommended.
Its hard to say definitively what the effect might be for your particular house, but I note the following.

You're venting warm air out through the insulation designed to keep heat in.
You're venting moist air past the vapour check designed to keep water vapour out of the attic.

With warm moist air hitting cold air and/or cold surfaces you run the risk of having a "wet" attic.

This may cause reduced effectiveness for any quilted insulation if the water condenses on it.
It may cause risk few frost forming on the inside of the roofing felt or on objects on the attic space.

Finally it may increase the moisture content of timbers forming the roof structure, which can cause twisting and cracking in extreme cases.
It may of course result in none of the above, but its as well to be aware of the potential problems and keep an eye out for them by checking your attic occasionally. :)


ONQ

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
How do you stop wind blowing clean through vents. A couple of mm of plastic of a closed vent is going to do nothing for keeping cold out and heat in if theres a huge whole in the wall behind it.
 
I don't write the regs AlbacoreA :)

You don't die from draughts, but you can die from lack of oxygen.
Its the lesser of two evils in relation to the old wall vents.
An illegal workaround were the old hit-and-miss vents.

I say "illegal" because the object was permanent "background" ventilation and a vent that can be sealed off doesn't supply this.
Now we're hearing waffle about on-demand vents, which sound like intermittent infiltration vents to me.
We don't seem to have moved on too far from the Georgian House after all.

We should be investing our time in -
(i) finding a cheap and affordable source of energy (hydrogen/oxygen => water cycle is the obvious one) and
(ii) dressing appropriately for the temperature and not expecting to be able to wander around in tee shirts in our houses.


ONQ

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
Most of the vents I've seen installed let almost as much air (heat & cold) and out when they are closed as when they are open. They are not "sealed" in any sane use of the word.

If the draughts are causing heat lost, thus, heating bills too expensive then someone can't afford to run it, especially older people then draughts could indeed kill someone indirectly.

I was really wondering is there a better low cost way. Some vent with baffles or something.
 
I'm always open to suggestions.

Its possible that the "on-demand" walls vents may satisfy some of the concerns you raised.


ONQ

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
LCO2D posted comments on this in a recent thread IIRC - but you'll have to search for it.

I Googled these results

Similar conversation on boards.ie
http://www.boards.ie/vbulletin/showthread.php?t=2056412454

On-demand vents.
[broken link removed]

No connection.
This is not a representation.
I am not endorsing their use.


ONQ

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
I'll have to inquire about them. Most houses seem to have a simple hole in the wall, then a simple plastic grill.
 
onq said:
Hi CBGB,

This isn't generally recommended.
Its hard to say definitively what the effect might be for your particular house, but I note the following.

You're venting warm air out through the insulation designed to keep heat in.
You're venting moist air past the vapour check designed to keep water vapour out of the attic.

With warm moist air hitting cold air and/or cold surfaces you run the risk of having a "wet" attic.

This may cause reduced effectiveness for any quilted insulation if the water condenses on it.
It may cause risk few frost forming on the inside of the roofing felt or on objects on the attic space.

Finally it may increase the moisture content of timbers forming the roof structure, which can cause twisting and cracking in extreme cases.
It may of course result in none of the above, but its as well to be aware of the potential problems and keep an eye out for them by checking your attic occasionally. :)"

Thanks ONQ. The attic has insulation between rafters. THe vents from the room below is then connected to a pipe which passes through the insulation board to the soffit. Then they sealed around the hole where the pipe passes through with expandable foam. I'm not a builder and this is what I was told they did and what I can see when I go up the attic. I though this would be fine, again with my very limited knowledge on the subjest as I thought a) the pipe carries the high moisture out directly out of the attic so it wont get cooled down inside the attic and b) they sealed all around the pipe to there is no breach in the insulation.
I have to admit I am sceptical at this stage. Does this sound anyway correct or do I put it in my growing list of "dont believe them when that say..."
"
Click to expand...
 
Sounds far too ad hoc to me. I would ask a mechanical and electrical consulting engineer to comment.
Unless the pipe itself is insulated it may allow the water vapour to condense within the pipe.
Water + air can result in bacterial infection - including [broken link removed].
Link relates to hotels with aircon systems, which may refer.


ONQ

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
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