Wind getting in at lean-to roof

[hastalavista]

The original question has not been answered though.

C

The question has been answered.
The consensus, based on what you have written, is that its not the flashing and the contributors were trying to eliminate other possibilities.

I have asked you twice for a specific answer to how the internal pb is fixed to the wall and if the wall vents in the block work are ducted out to, and sealed into, the face of the pb or is there a gap between the inner face of the pb and the block work. A visual inspection will require the inner grille to be taken off and if the hole in the pb is not big enough to shove your hand in then enlarge it to feel/see the gap if any.

This construction problem is widespread in 100's of houses all across the country, I have carried out remedial work on close to 100 at this point so I am aware, first-hand, of the issue.

You are quite entitled to rant on about your views on building regs and the like as well as exhibit a cynical and disparaging attitude to the current dearth of work for architects

I guess I should call some of my architect friends, they would be happy to get some work I suppose.

However it would be helpful if you could answer the question.

The above quote begs the question: why did you not engage with them earlier?

 

[onq]

I don't have high regard for building regs as they allowed the use of 9 inch cavity blocks to build the swiss cheese wind tunnell which we paid so dearly for.

Any form of construction must be sealed to prevent unwanted penetration by the wind.

I just don't buy the need for vents in every room.

The requirements for ventilation under Irish Law is given in TGD F Ventilation and depending on when your building was built.
There are two guides available online although an earlier 1997 document exists -
http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,22447,en.pdf (<br /> TDG F 2002)

http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1647,en.pdf (TGD F 2009)

These may help you assess the way the building should have been built originally.
If the upgrading of insulation has occurred recently, then these may inform you how to achieve compliance.

You could familiarize yourself with the law before approaching your architect in order to better prepare for the meeting.
There are alternatives as noted above - providing adequate air changes is a common sense requirement for healthy living - Posts #15 and #18 refer.

I advise against ignoring the law and rendering your building non-compliant with the building regulations.
This could have serious implications for the health of your family and your house insurance might not cover you in the event something occurs.

The original question has not been answered though.

Please read the thread posts again.
It was specifically answered in Post #6 above in terms of who should inspect.
The issue of whether and how this related to the flashing was specifically covered in Post # 10 above, which describes how the chase for the flashing might have cut into the block.

I guess I should call some of my architect friends, they would be happy to get some work I suppose.

This is what Post # 6 advised, because of

(i) the limitations of an online forum when dealing with an defect that requires an on site inspection
and
(ii) the possible limitations of laypersons when assessing technical matters involving building physics

​

Advice is only as good as the competence of the person offering it and the willingness of the person asking for it to take it one board.
Having offered what advice I can in this forum and included the relevant building regulations to guide you, I'll leave it at that.


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.

 

[chippengael]

The question has been answered.
The consensus, based on what you have written, is that its not the flashing and the contributors were trying to eliminate other possibilities.

Yes, and in that context we got into the sealed vents issue, which I don't think is the source of the problem, but which became the focus of subsequent discussion. Maybe I missed it, and if so I'm sorry, but how did we conclude the flashing at the roofline is not at fault?

I have asked you twice for a specific answer to how the internal pb is fixed to the wall and if the wall vents in the block work are ducted out to, and sealed into, the face of the pb or is there a gap between the inner face of the pb and the block work. A visual inspection will require the inner grille to be taken off and if the hole in the pb is not big enough to shove your hand in then enlarge it to feel/see the gap if any.

The vents are simply holes knocked into the cavity blocks - no ducting.

This construction problem is widespread in 100's of houses all across the country, I have carried out remedial work on close to 100 at this point so I am aware, first-hand, of the issue.

Fair enough, you know your stuff.

You are quite entitled to rant on about your views on building regs and the like as well as exhibit a cynical and disparaging attitude to the current dearth of work for architects

No, I actually do have good friends who are unemployed architects, and I am sorry for them. I wasn't being being cynical and disparaging as you suggest so lets not engage in name calling.

However it would be helpful if you could answer the question.


The above quote begs the question: why did you not engage with them earlier?

In my case, the insulation company hired a qualified architect to talk me through the project. She convinced me of the merit of doing the work, and carried out the BER examination at the end. She did not share your sense of alarm regarding the vents. Ultimately we did not see the insulation improvement we expected, and I have been trying to troubleshoot ever since.

 

[onq]

In my case, the insulation company hired a qualified architect to talk me through the project. She convinced me of the merit of doing the work, and carried out the BER examination at the end. She did not share your sense of alarm regarding the vents. Ultimately we did not see the insulation improvement we expected, and I have been trying to troubleshoot ever since.

This is the first time you mentioned the involvement of an architect.
This is a very important issue for you as the party complaining of non-compliant work.
Given the issues raised above by hastalavista and the undersigned, you should address your concerns to the insulation company and her.

Was a BER Certificate and Report issued to you after the work was carried out?
The benefit of insulation may be seriously compromised where there is an airflow within the structure allowing convection currents to reduce internal temperatures BEHIND the insulation.
In terms of knowledge of how building physics works this is a fairly basic issue and should have been taken on board when reviewing the likely performance of the upgraded property for a BER report.

Let me make it clear by way of an extreme example of a cold winters night.
Picture a house with 200mm of insulation separated from the house wall by a 100mm cavity.
In your case the cavity in question approximates the ventilated voids within the 215mm hollow blockwork

That 200mm of insulation is not going to achieve its potential if the structure surrounding the house is full of holes.
The temperature of the wall reduces towards the ambient external temperature because of the convection currents in the cavity.
Its like someone going outside on a winter's day who wears a coat but doesn't button it up allowing cold air to circulate inside near the body.

The house won't be quite so bad as if no insulation existed because the building will not "see" the night sky it might otherwise "see" without the insulation in place.
Radiant heat loss is reduced, but the convection currents in the cavity will lower the temperature of the wall they pass by significantly because they are at the temperature of the outside cold air.

Happy to stand corrected by any physicists reading this.
You should ensure any architect you ask to comment is competent in this area, otherwise you might be wasting your time.


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.

 

[chippengael]

Hi again,

To be fair, the architect did issue pre-project recommendations for vents:

Fan & Vents​

This dwelling has one or more fans/vents.
Fans and vents increase heat loss in a dwelling by allowing heated air to escape but
can be important in ensuring adequate ventilation. If there is no cover on the inside of
the vents, installing controllable vent covers will allow you to control the air flow
through the vents, and so can help reduce heat loss. All changes to ventilation must
comply with relevant Building Regulations requirements, particularly Part F
(Ventilation) and Part J (Heat Producing Appliances).​

Cost: Low Impact: Low

We made the decision to clover vents ourselves in rooms with no fires. Controllable vent covers on the inside of the rooms will do little if cool air is flowing around the structure compromising the efficacy of the external insulation.

The ingress of air into the structure was not as obvious post insulation, and we became aware of it over time.

As we were starting with such a leaky structure, my decision was to try eliminate as much as we could, and then add ventilation as required, eg. trickly vents on windows as we replace them, or even reopening the vents which is easily done.

I guess we will continue to try eliminate leaks as we go, and review the ventilation as required. I am still concerned that the roofline needs workthough.

Thanks

C