17 Jan 2016
14

 Solid Dot and Dab, it Importance

Why a Solid Dot and Dab?

We have been to the Derbyshire Peak District this week and air tested two great, but contrasting properties. We battles through some snow and ice to actually get to one of the properties but it was definitely worth it as it scored the best air test result we have ever recorded. This was made more remarkable as when we arrived at the property the owner was less than confident that he would even pass.

The Tests

When we initially put the fan on it was immediately obvious that the house was going to perform well. The owner told us that he had followed our air test check list and actually printed several copies out and gave them to each of his contractors, advising them to follow it closely. He said that throughout the build he had the air test in mind and at each stage of the build process he ensured that the air test was not forgotten.

His anxiety regarding the air test result was mainly down to the fact that the property had floating wooden flooring in a number of rooms and the skirting had not been sealed against the floor. Ordinarily, not sealing the skirting to the floor would have a detrimental affect, as in most cases a solid dot and dab is not done. However, as his plasterers had clearly done a solid dot and dab it meant that sealing the skirting was not necessary.

The second test in the Derbyshire Peak District was very similar to the first where there were a number of rooms with wooden floors. When we put the fan on it was obvious that there was a high amount of air leakage. On investigation it was identified that most of the air leakage was coming from the gap between the skirting and the floor but unlike the first property there had clearly not been a solid dot and dab to the plasterboard. The owner confirmed this and was quite shocked that we were able to identify this. However, all was not lost as part of our service is to stay and assist with remedial work. We assisted the owner to seal the skirting throughout the ground floor of the property and managed to get the air test score below the desired target. Luckily sealing the ground floor skirting achieved this, as the next option was to do the same on the first floor which would have been more difficult as the carpets had already been laid.

So why is a solid dot and dab to the bottom edge of plaster board so important?

1) It stops air leakage down the back of the plasterboard and into habitable spaces and saves having to seal the skirting to the floor, especially if you plan to have wooden flooring fitted.

2) If you are having carpets fitted the carpet fitters are likely to score out any sealing you have done so they get a better fit. So if you are not sure that there is a solid dot and dab make sure your carpet fitter does not score out and sealant.

3) The bottom line is that there should be a solid dot and dab to your plasterboard so insist on it if you are using contractors and if you are doing it yourself see 1 and 2. It will save you issues with your air test at a later stage of your build.

 

 

Phil Ramshaw (Director)

10 Jan 2016
example of a two fan set up in a doorway

Air Testing  in Yorkshire Case Study

Introduction

Northern Air Tightness Testing carry out air testing in Yorkshire and beyond. Our blogs are there to inform and help you when planning your new build and help you prepare for air test day. Whether you choose to use us for the test or not please feel free to have a look at our blogs, we hope you find them informative and helpful.

Following an email request from a building surveyor we were commissioned to carry out an Air Pressure Test of a office building in Leeds. The building was built over 12 years ago so at the time did not require an air test. However, the purpose of the test was to identify any areas of air leakage, as there were concerns about the building struggling to stay warm.

The air test was subsequently carried out on 23rd December 2015.

The method used to establish the ‘air tightness’ of the building is to use air moving equipment to establish air pressure differences between the inside and outside of the building. In this case the building was de-pressurised to allow us to identify air leaking into the building.

Under existing Building Regulations it is desirable to achieve an air pressure ‘score’ of below 10m3/m2/h. That is to say that under test conditions there would be less than 10 cubic meters of air escaping through each square meter of the building envelope per hour. However, the specific score required may be less than ten depending on design energy requirements.

As this building was constructed approximately 12 years ago it pre dates the requirements to be air tested to comply with building regulations.

On the day of the air test we calculated the building volume and envelope area so that we could obtain an air pressure score to indicate whether air leakage could be the cause of the building failing to stay warm.

The result we achieved was 12.14m3/m2/h.

Although this is above what would now be required under regulations it is not a particularly bad result for a building pre dating air test requirements.

Whilst the building was under test conditions i.e. de-pressurised, we carried out a survey to establish where the weakest areas were and it became apparent that the vast majority of air leakage was from the first floor of the building.

Further investigation was carried out which necessitated the removal of some of the ceiling tiles at various points around the perimeter of the offices on the first floor.

We found that the air leakage was caused by the fact that the internal skin of the building was not sealed adequately between the wall structure and metal roof.

We provided the customer with a video demonstrating air movement in the roof area and a number of photographs illustrating the lack of sealing between the roof and walls. We also made recommendations advising of remedial work and suggestions of additional insulation to the roof space.

If you require air testing in Yorkshire or anywhere in the north of England, either fill in your contact details or give us a call. Either way we will let you have our free air test check list to help you prepare.

 

 

Phil Ramshaw (Director)

23 Dec 2015
How to prepare for an Air Test

This depends on where you are in the build process. For the purpose of this article I am going to assume that the build is almost finished.

Firstly, make sure your air testing company is registered with ATTMA.

One of our favourite sayings here at Northern Air testing is:

”Treat every room as an air tight plaster board box” (What do we mean buy this?)

Well if you imagine a small bedroom and think about any penetrations there may be through the plasterboard. These are almost certainly as follows:

1) Where the plaster board meets the floor.

2) Where radiator pipes penetrate the wall or floor.

3) Under the window sill where the plaster board meets the sill.

4) Gaps between the floor boarding.

If the skirting is sealed top and bottom it will resolve issue 1

Proprietary fittings should be used where flexi radiator pipes penetrate to plasterboard, where pipes penetrate the floor the holes should be sealed, issue 2 is now resolved.

Under the window sill is often an area that is missed and is simply resolved with the use of some decorators Caulk issue three resolved.

Often flooring needs to be cut once it is down to access pipe work etc. The cuts need to be sealed once the floor is put back down. Issue 4 resolved.

You now have an air tight plaster board box (with controllable ventilation such as trickle vents) If we tested this room it would get a very low air test score.

Now think of every other room in the property in the same way.

Obviously bathrooms, en suites, kitchens, utility rooms have more penetrations through the plasterboard so take extra care. Remember that once your bath, vanity units and Kitchens are in it is more difficult to seal any penetrations.

So if you do treat every room in the same way as the small bedroom then you are going to achieve a very good air test score, as you will have minimal air permeability throughout the building.

Article Tips from How to Prepare for an Air Test.

  • Seal all skirting boards both top and bottom
  • Don’t have carpets fitted until the air test has been done. If you have to have the carpets fitted ask the fitters not to ‘score out’ the seal between the floor and the skirting.
  • Remember our plasterboard box saying.
  • Download our Air Test Check List.
  • Give us a call and we will be happy to offer you practical, free advice.

Article, How to Prepare for an Air Test by Phil Ramshaw (Director)

For SEO reasons the page title needs to appear a minimum of four times in this article.

18 Dec 2015
Air Testing Newcastle

Well, no air testing company should guarantee an air test pass and if they do we recommend that you walk away and use a more reputable company.

In our experience, builders large and small can sometimes fail an air test. This is often no fault of their own and can simply be an oversight during part of the build process. It’s not the end of the world and problems can generally be rectified quite easily. Here at Northern Air Testing we pride ourselves in offering our customers on site advice when a property fails. We will point out any areas of weakness and make suggestions regarding appropriate remedial work. We will even stay and help if that’s what’s required.

If you do fail an air test you should expect a post-test report outlining the areas of weakness. This will help you rectify the issues prior to a re-test. It’s also worth asking the test engineer where the issues are and get them to show you whilst they are on site. If you can, get them to put the fan back on and walk you through the property pointing out the weak areas and make a list there and then. This can be very beneficial as an experienced air test engineer will be able to identify the most problematic areas and thus the most important areas to pay attention too.

If you are reading this article it would suggest that an air test is worrying you which is understandable, the word test in any context worries me! However, some simple safeguards and processes throughout the build will make the test day less daunting. So take a look at our ”top five tips” and ”air test check list” on our website, click on the link and we will email them to you. There is no catch and no obligation. If your site is in Yorkshire we will even offer a free pre test visit, where we can advise you on how best to prepare for test day.

Today’s article Tips

  • Print off our check list and pin a copy in a prominent place in your build or site office.
  • Give a copy to all your trades and make sure they understand what an air test is.
  • If you make a hole in any plaster board wall make sure its sealed immediately, especially if it’s going to be behind kitchen units, baths etc.

Phil Ramshaw (Director)

Northern Air Tightness Testing Services LTD. (A Yorkshire based air testing company)

11 Dec 2015
Air Testing Yorkshire Van with green grass

Air testing can be a daunting experience for self builders and established building companies alike, but it needn’t be. Here at Northern Air Testing we are committed to helping our customers get through the air test with minimal difficulty. We can be available at a very early stage of your build to offer free information and advice to allow you to pass first time and take away some of the stress and anxiety associated with your air test. We also offer free pre test site visits and a free check list. Our free site visits were once described by a well known self build web site as ”an offer you can’t refuse”.

The free pre air test site visit offers our customers the opportunity to focus their attentions on the air test requirements at an early stage and allows them to instruct their sub-contractors to be mindful of the up and coming air test. Depending on how early we get involved in the build our advice can range from to following:

Solid dot and dab to the bottom of plasterboard.

This restricts the air flow from the cavity between the plasterboard and block work. From our experience most plasterers say that’s what they do and most developers say that’s what they ask for but, I’m afraid in reality 90% of the time it doesn’t happen.

Top Tip for developers. When seeking tenders for plastering work Ask for a quote to specifically include a solid dot and dab to the bottom edge of all boards.

Top tip for plasters. When tendering for work quote for solid dab and say why, It will impress developers that you have a knowledge of air testing and that you are conscientious.

Remember Northern Air Testing are here to help. We can offer information and advice at the early stage of your build but don’t worry if you have landed on this page at the end of your build and have just realised that you need an air test. We are very happy to offer you help and advice prior to your test. If you have a look at our website there are some useful