New House - Vents

[ClubMan]

Imagine you are travelling on a road and come to a signpost that says "Dublin,10km". What does it mean ? That you have to travel 10 km ? To Dublin ?

It could mean that there is a fun run ahead.

 

[z102]

Fun run ?! 1780 views and no end in sight ( smiley ) .....Some feel seriously attacked by logic and reality, no fun at all for those it seems.
It seems I've kicked another few torwards the road to progress.

 

[extopia]

I think heinbloed is right to point out that Technical Guidance Documents are, by definition, just a guide.

No one is arguing that buildings need adequate ventilation. The argument is about how one goes about installing a ventilation system.

To the original poster, it's a simple answer: do not block up your air vents unless there is an alternative source of adequate ventilation available. And while I like the thought, I don't think opening the windows regularly is the answer, because an awful lot of people (e.g. the kind of people who remove or block up wall vents) do not like drafts and are not going to bring them on voluntarily, except on a nice day.

 

[OCD]

Dunno here. Seems that I have never seen (anyone else?) 'holes-through-walls' in any other northern Europe nations, excepting our idol for mimicry, the UK.

You must remember that Ireland and the UK have different climates to the rest of Europe and what works in Spain or Finland etc. might not necessarily work for our climate. It is the reason we have the Irish Agrement Board.

Also the phrase "our idol of mimicry" shows a lack of respect to the knowledge base in the UK. Yes, these are Guidance Documents and while legally they may be unbinding I doubt you will find an engineer that designs against them. Similarly British and Irish Standards are best practice standards and you don't have to design to them if you can prove your theory another way but again, engineers will design to these standards.

Based on our technical knowledge, climate, etc. venting air in houses is important and you should take that from people in the industry who are dealing with this every day. I have yet to see heinbloed state his qualifications and therefore do not agree with his point. Blocking vents will lead to lives being at risk and there is no other way I can say that. You do not go to a doctor and tell them their diagnosis is wrong and similarly you should accept the opinion of engineers and others in the construction industry when we give our professional views. This is not a personal attack but I feel you should drop the view that venting is unnecessary. Reading a Technical Guidance Document doesn't make you an expert in the field so please leave it to those with the experience. To dismiss the Document as legally unbinding effectively means you are ignoring the research work, practical knowledge and feedback from thousands of engineers/tradesmen/fire servicemen etc. and millions of man-hours of these people that have gone into writing, re-writing and continuous update of these documents. Please don't wave your pen and dismiss this just because you have a little bit of knowledge about the subject and of what they do in other countries.

 

[extopia]

I don't believe that heinbloed has ever said that venting is unnecessary. His point is that there is a case to be made for passive versus active ventilation, and that advocates of active (i.e. "hole in the wall") ventilation might illustrate the cost/benefit analysis of their case. That is to say, how does the cheaper cost of installation of hole vents stack up against a more expensive ventilation system in terms of payback time by way of heating costs saved, etc. This is standard analysis that any qualified advocate should be able to do off the top of their head.

 

[Max Hopper]

You must remember that Ireland and the UK have different climates to the rest of Europe and what works in Spain or Finland etc. might not necessarily work for our climate. It is the reason we have the Irish Agrement Board.

You are winding us up, yeah? The UK and Ireland have a micro-climate unparallelled in northen Europe? Even your choice of the weasel phrase, 'not necessarily work', demonstrates a lack of confidence in the subject.

Step back a moment and look at all the nonsensical laws and statues there are. Now you would agree that many of the more whimsical were enacted to deal with a single issue, problem, personal gain, or as a vendetta.

Building codes and guidances accumulate in a similar fashion. I submit that if the origin of the 'hole-in-the-wall' guidance could be traced to it's origin, it would probably be about the era when to paraphrase an earlier poster, the locals were living in mud huts with open heat sources (turf fires). Indeed, the image of the plains dwellers of north America in teepees with smoke curling from the tops of their conical dwellings springs to mind.

And what with the swell of publicity concerning the boundless errors in the medical profession and Health Service, you would be foolish to accept a diagnosis for anything more than external injuries and the common cold (and there, with the increasing number of avian flu cases, most GPs in all likelihood would mis-diagnosis).

Get over yourself and ask for a second opinion.

 

[OCD]

Max Hopper / Heinbloed,

It feels like you're trying to turn this into a slanging match and that's not what it should be about. The original post said that they had moved into a new bungalow and were considering seaking the vents up. From my point of view, which is technical, I totally disagree with blocking vents but maybe from your point of view, money, vents are an unnecessary waste.

I am not here to tell you what they cost in terms of heat loss but I have designed and lived in many types of house and vents are not just for rooms with a combustible fuel source. Whether the vents are in the windows or in the walls it doesn't matter. As I said before, in disputing this you are effectively negating thousands of professional views on the subject and if you are adamant that they are not needed then please give everyone your qualifications and background so that other readers can make up their own minds.

Venting not only reduces the risk of CO poisoning from fuel sources, it also reduces the risk of Radon poisioning from the ground, dampness from condensation and the general airing of the house. If you go into your attic and notice the slight breeze, check the colour and moisture level of the timbers and they will be ok....seal the attic from this airing and you will get dried out timber, cracked slates and water ingress, i.e. the vents in your roof are important in doing a job. Similarly, the vents in the walls or windows or doors on the other floors are doing a job - a very important job.

I'd rather not write again in this post so you can have the last word if you so wish but if you do choose to respond, at least give the readers a professional technical reason for views that vents can be blocked. I think everyone would be interested to see them along with your qualifications behind your reasoning. I fear that you have a little knowledge of engineering and that can be a dangerous thing when you are dealing with people's lives.

 

[Max Hopper]

...effectively negating thousands of professional views

Substantiation?

...seal the attic from this airing

From 'holes-in-the-walls' to holes in the soffitting. There is a stretch!

...a little knowledge of engineering and that can be a dangerous thing when you are dealing with people's lives.

Are you referring to the fact that anyone can operate as an architect in Ireland?

The vagueness of statements akin to 'health and safety reasons' and 'dampness and stale air' (Google throws up hundreds of links with the CO issue, BTW) leaves me sceptical. And if a handful of idiots annually die from 'misadventures', so be it. The gene pool does need occasional doses of chlorine. I maintain that the 'holes-in-the-walls' solution is an antiquated device as are damperless fireplaces.

 

[z102]

From a structural engineer – which OCD (unnecessarily) claims to be – one would expect a.) knowledge of the building regulations, b.) competence to use a calculator and presenting the results ( 2 exchanges of 20degrees warm air in the average sized living room exchanged with out side air in winter time is how much in kilowatts blown into the wind ? ) and c.) ability to present an opinion using references.
How the original poster should tackle his/her problem was not even once spoken about by OCD.
He is taking us for a ride. Some need to act like that, psychology .
There where many more questions, I take a few:
Clarecelt was thinking about using ducting through the house , taking the stale air out.
Yes, that can be done. But when not employing a heat recovery unit than
think about how the expelled air has to be replaced. And when running
air ducts through rooms that are occupied by different persons (different
owners/appartments) then you should equip the ducting system with fire flaps. This is
also the case when going through several storeys. Fire flaps automatically
close when there is a fire, fires love to spread via air ducts. I don’t know if
these are required by any legislation in the private single family house but
they are worth it.
Serontosid wanted to know if air vents in the window frames are legal. Yes, they are.
But they are no replacement for a properly sized window opening (tilt and
turn or simply turn) nor can they alone provide a room with adequate
ventilation on their own. And they are not energy wise, a punctured
window frame insulates badly.
Gegee wanted to use flaps on ventilation pipes. No problem, as long as the pipes are
horizontally leaving the wall to the outside. If they stick vertically into the air
then hoods can be put on top , they look somewhat like cowls. That would at
least break the wind somehow, many sewer pipes –going up outside the wall-
are not fitted with those , they should be so, watch the water level in the toilet pan moving when the wind blows strongly (smiley).

 

[quinno]

As a building surveyor and corporate building engineer, I have observed some of the posts aimed at OCD and they appear to becoming personal. I am not here to judge qualifications, or to back up my own to a bunch of strangers, but as a structural engineer he has reached the prescribed level of education and experience to offer such advice. I am also not going to get into a debate or slagging match about my own qualifications and experience (12 years in total). These are currently in front of the Dail in the form of the Building Control Bill 2005 and it is they (not you) that will be eneacting this in legislation. This Bill will, once enacted, protect ‘Building Surveyor’ as a registered title (incidentally, Max Hopper, this will also include ‘architect’ and ‘quantity surveyor’). In short, I know what I’m talking about.

The advice Hienbloed has given shows a keen interest in green building, what one would call amateur interest, without being backed up with a sound education and knowledge of building construction and regulation, particularly in Ireland. Not all of this advice is bad, he certainly is passionate about the subject, and I for one am as interested in green issues as the next. Simply dismissing and criticising the system we have in place here is useless – there are laws of the land protected by statute that we have to all abide by. Further comments by Max Hopper appear to be just plain inflammatory and show a complete ignorance of what we are trying to achieve by ventilating space. Incidentally, wall vents are used in other countries, including the US, Australia and throughout the EU to achieve passive natural ventilation in houses. Timber roofs particularly need ventilation – they will simply rot otherwise. The dry rot fungus (Serpula lacrymans) is everywhere, in the air, in and on timber, everywhere. It loves warm, tranquil, humid spaces to breed and reproduce. It can also grow invisibly through wood fibre, akin to ivy growing up a tree, so an out break at one end of the house can infest the entire property very quickly. It is very difficult to treat and eradicate (never mind the expense) once it gets a hold. Only one spore germinating causes an outbreak, which can lead to potential structural failure and a nasty repair bill. To the people reading posts, I would say take from it what you want, but seek sound professional advice from a recognised professional (with professional indemnity insurance) before pursuing these ideas further.

The need for adequate ventilation has been recognized in buildings for years. From the middle ages, it was recognised that ventilation was required to prevent transmission of diseases, as well as preventing poisoning from open fires. Scientists such as John Mayow conducted experiments in the 17th century to elaborate on his observations regarding ‘igneo-aerial particles’ (subsequently discovered to be carbon dioxide) that caused asphyxiation in mice. The science behind the need for ventilation is well recognized. I am not going to go into what is already well known and documented and researched subject, far beyond some of the ‘pub advice’ offered here. What people have confused here is ‘Regulation’ (in the form if the Building Regulations themselves) and Guidance (in the form of the Technical Guidance Documents oft referred to here). In the requirements for ventilation, the Building Regulations are specific and simply state (under Regulation F1) … ‘Adequate means of ventilation shall be provided for people in buildings.’ The Technical Guidance Documents indicate how this can be achieved. Not following the TGD’s to the letter is not a breach of the Regulations per se, however you need to satisfy the Building Control Authority (not me) that you have satisfied the Regulations if you are coming up with alternatives. This will generally require a good sound understanding in the principles of what is involved, as well as some detailed calculations. Compliance with the TGD’s is prima facia compliance with the Regulations. How you do that is up to you, you can invent or innovate whatever means necessary, it is not me you will have to convince. Also, if you undertake alterations to your house that you subsequently decide to sell on, you may be obliged to change these back in order to comply with the Regulations. You might lose the sale as a result.

The basic requirements, in terms of human comfort, are to provide:

Adequate air changes in the space being ventilated. A rate of 16 l/s per person was recognized as early at the beginning of the 19th century as being adequate to achieve comfort. This can be achieved by an air change rate of 0.5 – 1.5 times in the ventilated space. Further details can be found from recognised bodies such as the Chartered Institute of Service Engineers (CIBSE), they also appear in some of the appendices that accompany the Technical Guidance Documents. If any one wants to maybe advice them how they’ve being erring in their ways all this time, feel free to email them your ideas.

Lowering of CO2 (carbon dioxide) concentrations – a concentration of 1000 p / pm generally leads to the ‘stuffiness’ and ‘drowsiness’ experienced in a poorly ventilated space. Increased CO2 in an environment leads to the body hyper ventilating, that is breathing deeper to increase the intake of oxygen (you might notice how you tend to yawn in such an environment – this is the body trying to absorb more O2 from the air into your blood stream). This exacerbates the cycle in that the free oxygen in the air is used up and converted to CO2, further increasing CO2 concentrations. In the extreme, CO2 poisoning can lead to unconsciousness.

Lowering of concentrations of other gases – as well as CO2, CO (carbon Monoxide) is one of the main gases created by open fires and combustion sources (gas cookers, oil boilers, etc). CO is a particularly nasty gas in that it is colourless and odourless, you do not know that you are breathing it usually until it is too late. The CO molecules attach to the blood haemoglobin in your body, this prevents the uptake of O2 (oxygen) that you need to live. This is why so many people that survive house fires subsequently succumb to its effects – their haemoglobin is so saturated with CO that they cannot absorb O2 into the blood stream. CO Concentrations above 70 ppm will generally cause feelings of being unwell, with 150 – 200 ppm are fatal. If in doubt, buy and CO detector.

In addition to CO, radon is a radioactive colourless and odourless gas that is present in Ireland (details of your area can be found at www.rpii.ie). Radon is a gas formed by the break down of minute deposits of uranium in the soil. It is particularly prevalent in semi-porous sub-strata (such as limestone) where the gas can percolate freely upwards. Protection from radon is legislated for within the TGD’s, there are there for a reason. Lack of ventilation can lead to unacceptable levels of radon building up (above 200 bq / m3 is considered dangerous to health, and increases the risk of lung cancer).

Lowering humidity in the air – humidity is one of the contributory causes for breeding of fungal (dry rot) and bacterial (Legionella, amongst others) agents. We suffer from almost year round high humidity in Ireland (quite different to Finland and Spain, as OCD pointed out) and resultant high levels of dry rot. Nearly all buildings in Ireland act as a potential incubator for the dry rot fungus. We also breath out moisture in our breath. This leads to condensation, if not ventilated properly.

Posts on this forum have seen the need for ventilation as being almost heinous, and have confused the need for airtight buildings with the need to ventilate adequately. Natural passive ventilation is compatible with ‘green building’. It is after all free, and if installed correctly, the heat loss from ventilation can be less than the capital costs of installing and running alternatives. Better solutions than the bare minimum bog-standard ones found en-mass here can offer adequate ventilation, as well as offering satisfactory levels of temperature control, acoustic damping and minimal heat loss. The EPBD Directive, currently under consideration by the Dail in the form of the Building Control Bill 2005, recognises this and orders EU member states to implement the directive and adopt it under their own legislative framework. Article 3 recognises the need for ventilation and specifically states implementation of the directive (where ventilation is concerned) should be undertaken in such a way as to ...’avoid possible negative effects such as inadequate ventilation’. Some posts have suggested here bthat we should eleminate ventialtion altogether an live in an air tight box.

And, Heinbloed, if you want to work out your ‘..2 exchanges of 20degrees warm air in the average sized living room exchanged with out side air in winter time is how much in kilowatts blown into the wind ?’, I refer you to appendix E1 of Part L of the Building Regulations 2002 – Technical Guidance Documents which demonstrates how to calculate elemental heat loss from a dwelling, including an allowance for ventilation. These calculations are based upon EU directives, absorbed into our legislation and enacted by this Regulation. They are also used EU wide under this directive. If you are struggling with this, seek the advice of a building professional.

 

[Sue Ellen]

Hi Quinno,

Thank you for taking the time to post your obviously well thought out/informative reply.

As all views/arguments on this subject appear to have been expressed at this stage and Bertson's query has been dealt with IMHO it is best if we close off this thread now.

Thanks to all who have contribued.

Sueellen.