Why most new Irish Houses are crap (Part 2) ~ Airtightness

Following on from the previous rant, this blog post (rant) continues the theme of the problems concerning Building Control in Ireland and focusses this time on airtightness.

The main problem is even though the legislation exists there is no one to adequately enforce it. Ireland is a nation of self-builders, the power to self build is in the blood going back generations when the family homestead was constructed in local stones and timbers salvaged from the sea. There now exists a gulf between how the self-builder constructs and what the Building Regulations require of him/her. This difference is left to be enforced by the supervising architect or engineer as there is effectively no Building Control in Ireland (next rant!). Corners were being cut in the boom time Celtic Tiger Ireland and more corners are being cut now as money has become increasingly difficult to find. It’s only because I’m switched on to airtightness (I’ve done the same course that the contractors would do plus heaps of additional training, passive house courses etc), explain the benefits of airtightness and then insist on the air pressure test being done that it actually happens; my guess is (and remember it’s only a guess) that there’s a lot of self builders who don’t understand the importance of a draught-free house, don’t want the additional expense/hassle and are desperate for the release of funds from the bank that they are trying to get their house signed off without the test.

Don’t forget that you’ll also get a better BER rating when the airtightness test is complete as the result is fed into the DEAP calculation rather than using the default figure of 10.

A minor diversion for a minute: airtightness is the wrong name; a better phrase would be ‘draught-free’. Airtightness conjures the idea of suffocating in your house, stuffy, air-free rooms. A better way to sell the concept is ‘draught-free’ – a house where there’s no freezing cold draughts down the back of your neck in winter. It’s often forgotten that even in the most air-tight house with heat and air recovery; you can still open a window! Opening 2 opposite windows to create an air cross flow will change the entire air in a room in 10 minutes.

The airtightness test is obviously important but the end result requires an air tightness strategy at drawing stage. The way to test your strategy is to place a pencil on a section through the drawing and then draw around the entire envelope and airtight barriers without lifting the pencil once. If you have to lift the pencil (where the airtightness barrier is missing at the junction beteween a window and wall for example) it means you will have an air leak.

My recommendation is to employ an architect that understands airtightness (ahem), a contractor that has done an airtight house previously and has completed a course by one of the airtightness specialists and YOU to go on a contractors course too-you’ll learn a heap and know when the contractor is doing things right (and wrong!)

If you are an airtight membrane specialist such as Ecological Building Systems or Siga, please comment and feel free to plug your wares. As always, comments welcome…

Below are few photographs from recent airtightness test on new, one-off house; first house done by Mayo Contractor that has basic level of airtightness. Current Building Regulations are 10ac/h(which is crap); result after preliminary test (few parts still to fill) was 4.9, still not brilliant, twice as good as building regs but still not low enough (results <3 are forecast in next regulations update).

Notes on photos:

The air test needs to be conducted below a specific wind speed, hence the anemometer.

Door removed and fan blower door installed.

Next rant on Building Control and the lack of it in Ireland, no holding back on this one!

Blog post by iPhone

0 thoughts on “Why most new Irish Houses are crap (Part 2) ~ Airtightness

  1. Great piece Mark. Airtightness is all about build quality. Putting up flat pack houses as quickly as we have for the last decade means many houses built relatively recently can be leakier than those built 50 years ago including my own unfortunately! Having clear, effective, buildable details at design, a conscious and coordinated approach on site where all crew understand what you are trying to achieve and how to achieve it, and finally a test to confirm your result are critical. Unfortunately we have a steep learning curve in this country for builders and dare I say many designers too. Improved building control is critical along with a greater appreciation for airtightness in our education system for designers as well as more training for building professions (electricians, plumbers, plasterers, insulation installers, etc). While companies like us are training, I think the government should provide independent training in this area to up skill many unemployed people in this area now. We need a combined approach, to design, build and then test for airtightness.

  2. Hi Lads
    Agreed about the education side of things we too suffer same as yourselves in uk
    We are trying to stimulate conversation on the subject by tweeting and blogging.
    We like the Draughtfree angle this is good and totally with you on this one.
    The way to educate is onsite training being there when your plans come to build – its the only way lads – training starts we the folks that have been trained ie you – its got to be passed on or we will all go round in circles.
    The air test results 4.9 are average as the uk so we wish you luck with this one.
    Education is the key lads education but not only ranting on blogs get out there in the thick of it an teach
    nice speaking to you.


  3. Dear Mark,
    I couldn’t agree more with your assessment of the situation here in Ireland, an excellent and accurate article .

    You mentioned that if one wishes to plug some products, well I represent several companies that are active in Ireland and the UK.
    Isocell has been providing airtight solutions to the building Industry across Europe for nearly 20 years we manufacture and supply a comprehensive range of products for achieving airtightness in all types of build, whether that be timber frame masonry or block build.
    We have been supplying product and solutions in Ireland and the Uk for over 3 years , if anyone is interested in learning more please contact me http://www.isocell.at . German eco homes have used these products on their passive house in Swords , and achieved 0.58 ach on the first test, we can also arrange a supply and fit service, as well as advice for new builds and renovation projects.
    Also if anyone is interested in full shell systems designed to meet low energy or passive standards let me know, as well as high quality timber / alu clad doors and windows double and triple glazed for low energy and passive builds as well standard builds,maybe you have some clients for whom this could be of interest.. I can supply and advice on all of the above. Kind Regards Stuart stuartprause@yahoo.ie 0866018555

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.