Frequently Asked Questions

• When is a BER required?
• Why do we need a BER?
• How much does a BER Certificate cost?
• What do you get ?
• What is Thermal Imaging?
• What is Air Tightness Testing?
• Do I need Air Tightness Testing?
• How do I improve the energy efficiency of my home?
• Where can I get more information on BER/Energy Efficiency?

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Air Tightness Testing FAQs

• What is air tightness?
• Why is air tightness important?
• Is air tightness testing mandatory?
• Which buildings need to be tested?
• When does testing take place in the construction process?
• What information is required to produce a quote for air tightness testing?
• What preparation needs to take place in advance of testing?
• What does air tightness testing involve?
• What is the envelope area?
• How is air tightness calculated?
• When will I get the results?
• What happens if the building fails?

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When is a BER required?

The requirement to provide a BER is being introduced on a phased basis as follows:

• applications for new dwellings from 1st January 2007
• new non-domestic buildings from 1st July 2008
• existing dwellings and existing buildings offered for sale or rental from 1st January 2009

Why do we need a BER?

A Building Energy Rating (BER) is a requirement of the EU Directive on the Energy Performance of Buildings (2002/91/EC of 16th December 2002), which has now been transposed in Ireland by the European Communities (Energy Performance of Buildings) Regulations 2006 (S.I. No. 666 of 2006).

The Building Owner is required to provide the BER to prospective buyers and tenants. BER will, therefore, make the energy performance characteristics of the building transparent to prospective buyers and tenants. As a result, buyers and tenants will be able, for the first time, to take energy performance into consideration in their decision to purchase or rent a building.

How much does a BER Certificate cost?

The cost of the BER Assessment is dependant on the following elements - no one dwelling is identical to the next.

• Size
• Complexity
• Survey Requirements
• Availability of Technical Information

There is a maximum fine of up to €5,000 for not having a BER cert when required.

What do you get ?

Along with the BER Cert we will provide you with a detailed report which will outline whether or not the house is complying with the building regulations (in terms of energy efficiency)

What is Thermal Imaging?

Thermal imaging is used to identify patterns of heat loss from your property. The pattern of heat loss through the fabric of the building and heating systems can be determined by the use of a high tech infrared camera, whereby points of possible concern show up clearly as hot or cold in relation to their surroundings.

Thermal Imaging is ideal for:

• Detecting paths of air leakage,
• Determining adequacy/inadequacy of insulation
• Inspecting under floor heating, domestic and commercial
• Inspecting meter boxes for over-heating

What is Air Tightness Testing?

Air tightness is essentially about is the elimination of draughts. The less cold air that we have to heat the better – so the air tightness performance of a building can play a huge part in increasing energy efficiency, identify areas of heat loss, reducing heating requirements and saving money.

FER assist architects, developers, self builders and homeowners achieve targeted air tightness levels with advice, accurate air leakage measurement and infrared analysis.

Do I need Air Tightness Testing?

An Air Tightness Test became mandatory for all new homes from the 31st June 2008.

How do I improve the energy efficiency of my home?

FER Recommends:

• Book a building energy rating audit for your home with FER
• Use ‘A’ rated kitchen appliances
• Switch from fossil fuels to cleaner renewable energy heating systems
• Insulate your hot water tank and attic
• Draught proof your doors and windows
• Switch off all electrical appliances and computers when not in use
• When replacing windows, purchase windows with the lowest possible u-value
• Use low energy lighting throughout your house
• Install thermostats on all radiators
• Install a condensing boiler
• Upgrade the heating system with Time and temperature zone control

For more energy saving tips visit www.sei.ie

Where can I get more information on BER/Energy Efficiency?

Please visit the SEI (Sustainable Energy Ireland) website

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Air Tightness Testing FAQs

What is air tightness?

Air tightness, air leakage or air permeability all refer to the infiltration of cold/hot air into the building and/or the loss of heated/cooled air from inside through gaps, cracks, holes, etc in the building fabric.

The loss or cooling/heating of this 'conditioned air' through 'uncontrolled ventilation' affects the energy consumption of the building, as additional energy will be required to re-heat or re-cool the air. It also impacts on the comfort levels of the building occupiers.

Why is air tightness important?

Air tightness plays a significant role in the energy efficiency of buildings.

Because:

• a link has been established between carbon emissions and global warming
• the production of energy emits carbon
• the built environment contributes about 50% of carbon emissions
• heated/conditioned air leaking from buildings requires the use of additional energy to maintain temperatures

By limiting the leakage of heated/conditioned air from buildings, it is possible to reduce energy consumption and costs.

The government has made commitments to reduce carbon emissions through the European Energy Performance of Buildings Directive (EPBD) and the Kyoto Agreement.

Part L is their method for addressing the conservation of fuel and power in buildings based on their overall 'Emission Rate' and as such places performance requirements on air tightness. Performance is proven through site testing of the completed building.

Is air tightness testing mandatory?

Yes, buildings need to demonstrate a minimum level of air permeability (10m³/(h.m²)) and in the majority of cases this is done through an on-site, pre-completion test.

This is not an onerous requirement in itself but the design air permeability for a particular building may need to be lower to achieve the overall carbon emission rate for the building and/or client specification.

Which buildings need to be tested?

• All new dwellings (based on a sampling rate)
• All new buildings other than dwellings
• 'Large' Extensions to buildings other than dwellings

When does testing take place in the construction process?

Basically when the building is completed, typically everything has been finished apart from the carpets being laid. But before handover.

Inviting the test body to site too early is likely to jeopardise the result, making testing impossible or not meeting the requirements of the building inspector.

This does place extra pressure on getting things right first time, remedial works at this stage may be awkward and cause expensive delays.

It is important that the air barrier is complete and any penetrations have been fitted and finished.

For dwellings we have produced a checklist to gauge whether the units are sufficiently complete.

What information is required to produce a quote for air tightness testing?

For dwellings, sufficient information is required to identify the different dwelling types and the number of each eg General Arrangement/Site Plan and Schedule (including other important details such as variation in storey height or construction method).

For buildings other than dwellings, the approximate envelope area is the key factor for quoting. It is required to establish the necessary fan arrangement. This affects the time on site and potentially the number of people. This can be calculated from drawings – floor plans AND elevations.

What preparation needs to take place in advance of testing?

We provide a simple checklist for building preparation, which includes the following:

• The building should be 'completed'
• All external doors and windows closed
• All internal doors wedged open
• All fire dampers, ventilation louvres and trickle vents closed but not sealed
• Mechanical ventilation turned off with inlet/outlet grilles sealed
• All combustion appliances switched off
• Drainage traps must contain water

This needs to go to site. The preparation would ideally be undertaken by the contractor in advance of the test body arriving on site to maximise the testing time in a day. Flynn's Energy Ratings will undertake the preparation where this has been arranged in advance.

For dwellings it may also be necessary to agree the test programme with the building inspector before arriving on site.

Where possible, it is helpful to accurately calculate the envelope area and confirm the fan installation arrangements based on architectural drawings before coming to site.

What does air tightness testing involve?

The objective is to measure the volume of conditioned air escaping through the building envelope via uncontrolled ventilation at an induced pressure difference of 50Pa.

The following basic steps are typical:

• Check site preparation / Prepare site – including temporary sealing
• Calculate the envelope area if not done previously
• Explain the process to relevant staff and sub-contractors working on or near the building
• Take environmental condition measurements – wind speed, temperatures, barometric pressures
• Install template(s) into suitable aperture(s)
• Install fan(s) into template(s)
• Connect monitoring equipment
• Check the static pressure
• Take multiple pressure difference readings and record fan flow rate(s) – allowing sufficient time for the pressure readings to stabilise
• Check the static pressure
• Process the readings through appropriate software – check that readings fulfil the requirements of the standard
• If the building fails, attempt to identify/quantify air leakage/infiltration paths
• Disconnect measurement equipment
• Remove the fan(s)
• Remove the template(s)

What is the envelope area?

The envelope area is the total internal surface area of the conditioned areas of the building ie the sum of floor area, wall areas and ceiling area (of the heated space).

How is air tightness calculated?

Air permeability is essentially a function of the pressure difference between the inside and outside of the building and air flow rate through the fan(s) to produce that pressure difference. This is averaged out over the envelope area.

The result takes account of environmental conditions.

The final air permeability at 50Pa is based on a logarithmic graph of pressure difference and flow rate, the graph should:

• Have at least 7 points (ideally 10 or more)
• The highest figure should be at least 35Pa but preferably would be in excess of 50Pa and ideally higher than 60Pa
• The lowest figure should be at least 10Pa or 5 times the 'static pressure' (the pressure difference between inside and outside without the fans) – which in itself MUST be less than 5Pa to limit uncertainty
• The readings should be no more than 10Pa apart
• The correlation of the graph should be at least 98%
• The gradient of the graph (n) should be between 0.5 and 1.0

When will I get the results?

An indicative result is available immediately result and report are posted out within two working days

What happens if the building fails?

At Flynn's Energy Ratings, we will endeavour to help you identify the probable air leakage/infiltration paths.

There are a number of methods we employ to do this of increasing complexity:

• Smoke pencils – smoke can be used to identify where air is moving when the building is being tested
• Depressurise the building – we tend to pressurise the building under testing which forces air out, by reversing the fans and depressurising the building air is drawn in and normally can be felt or even seen as 'draughts'
• Smoke testing – if the air paths are less direct it may be necessary to use smoke puffers and/or fill the building with smoke and pressurise/depressurise again. Points of air ingress and egress should be identifiable.
• Thermography – if it is still not apparent where air is escaping, infra-red cameras can be used to identify hot spots and cold spots on the internal and external surfaces of the building. This requires a temperature difference between the inside and outside and is usually done at night.

In the vast majority of cases the first two methods are sufficient to identify the most significant air leakage paths. These can be temporarily or permanently sealed and the test repeated to quantify the effect of addressing these areas. Where problems are larger and/or cannot be addressed on the day, the building may need to be re-tested at a later date.

For dwellings, the same unit should be tested, plus another example of the same dwelling type (assuming one exists).


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