2. Draught Finder Air Tightness Inspections Finding Air Leaks
Trevor Clark
Draught Finder
Qualified Air Tester & Thermographer
Non Destructive Testing
Accredited by Independent Airtightness Testing Scheme
Member of UK Thermography Association

3. Air Tightness Inspections
6. Finding Air Leaks
If air is invisible, how do you find leaks?
By using one of three methods;
1. By feeling the airflow !
2. Infrared Thermography
3. Special Smoke

4. Our Thermal Infrared Camera DOES !
Air Tightness Inspections
Finding Air Leaks
1. By feeling the airflow !
Our hands have lots of nerve ends which can detect heat and air movement due to the cooling effect of airflow over the skin, especially the back of the hand when wet!
Then, by systematically going around the building and closing the internal doors when can establish where the air leaks are worse, as the door wants to close quicker in these rooms!
Entering the room and looking for air leaks from experience we can find a lot of leaks purely from noting the temperature of air flowing over our hands
But neither of these two methods are as quick or accurate as using a thermal camera. Also they don’t provide information as to where EXACTLEY the air leaks are located for repairs.
Our Thermal Infrared Camera DOES !

5. It can be quite dramatic as smoke billows out from the building.
Air Tightness Inspections
Finding Air Leaks
3. Special Smoke
If air is invisible, how do you find leaks?
We can use a Smoke Pencil
This technique is used when the building is under “Positive” pressure.
Or for large buildings a Smoke Generator
It can be quite dramatic as smoke billows out from the building.
But we need to inform the Fire brigade or . . .

6. Air Tightness Inspections
Finding Air Leaks
3. Special Smoke
We can use a Smoke Pencil
The fan is set to Pressurise the building and the Inspector works from inside the building.
The ‘Smoke Pen’ is moved to where air leaks are suspected.
The smoke is drawn to the gap and pulled through. The gap is then sealed.
The fan is set to Pressurise the building and the Inspector works from outside the building.
The ‘Smoke Generator’ fills the building with smoke.
The smoke is comes out of holes or gaps. These are sealed.
Or for large buildings a Smoke Generator
Using smoke takes time!

7. Air Tightness Inspections
Finding Air Leaks
2. Infrared Thermography
Why?
Advantages of Non-Contact Thermography
1. Safety – Safe inspection of operating plant such as electrical systems, power can be left on during inspection. No disruption
2. Remote – target can be inaccessible to contact instruments or in motion. High ceilings
3. Non-Intrusive – some materials can be damaged by contact or could change temperature with contact.
4. Measurement Speed – objects that are changing rapidly in temperature or moving can be measured.
So many uses;
Powerful
& Accurate!

8. Air Tightness Inspections
Finding Air Leaks
2. Infrared Thermography
Air is also a good energy transporter.
As such it will transfer heat as it searches for a way into or out off the building.
This air leaves an trace “pattern” behind, due to this energy transfer.
Provided there is enough difference in temperature we can “SEE” this trace pattern.

9. Air Tightness Inspections
Finding Air Leaks
2. Infrared Thermography
To “see” the air leakage area we use our
Infrared Camera.
This technique is used when the building is under “Negative” pressure
It is quick, accurate and non-destructive, with minimal disturbance.

10. Combined Air & Thermal Inspection
Air Tightness Inspections
Finding Air Leaks
2. Infrared Thermography
Combined Air & Thermal Inspection
The Power of Combining these Technologies
1 + 1 = 2
NOT always,
Sometimes the sum of two items exceeds the sum of the individual components
By COMBINING these two technologies we increase the power of both to create ONE VERY POWERFUL TOOL !
Sometimes …
1 + 1 = 4

11. Air Tightness Inspections
Finding Air Leaks
2. Infrared Thermography
Consumer Unit
Before the fan is switched on,
Yes a problem, but …
Within 5 minutes of fan running
Turns out to be a MUCH BIGGER problem altogether!

12. Air Tightness Inspections
Finding Air Leaks
2. Infrared Thermography
EXAMPLES
Ceiling Rose
Air Leak via cable entry

13. Air Tightness Inspections
Finding Air Leaks
2. Infrared Thermography
EXAMPLES
Light Fitting
Air Leak via cable entry

14. Air Tightness Inspections
Finding Air Leaks
What is the benefit of sealing air leaks ?
Sealing Draughts (air leaks) is one of the ….
MOST EFFECTIVE
CHEAPEST
PERMANENT
Means of increasing the energy performance of ANY building.
And the MOST cost effective way to LOWER heating bills !
An INVESTMENT that could produce a return of 20% or More! year on year! (depending how draughty it is now!)

15. Air Tightness Inspections
Finding Air Leaks
What is the benefit of sealing air leaks ?
Lower ENERGY RUNNING COSTS, less energy input
Improved COMFORT CONDITIONS, steady temperatures
Improved INDOOR AIR QUALITY, providing sufficient ventilation is installed
Quicker HEAT UP TIME, retaining heat longer.
Less DIRT & GRIME, brought into the building, Reduced Washing cycles
Improved INSULATION PERFORMANCE, prevents air blowing through or around insulation
Improved ACOUSTIC PERFORMANCE, less noise transmitted
Improved OCUPANCY SATISFACTION, fewer complaints from tenants, reduced rent disputes
Avoidance of moisture related BUILDING DAMAGE, lower maintenance
Lower ENERGY CAPITAL EQUIPMENT COSTS, smaller replacements required
Improved BUILDING STANDARDS, Builders take more care when building
Less CO² used in heating or cooling – Helping Government meet CO² reduction targets
Air flowing through and around insulation takes heat away rapidly, ruining the insulation performance. Energy Auditors take the U value calculation and reduce it by a factor of between 25 & 50% after looking at the gaps in poorly installed insulation.

16. If you had a hole the size of a football in the lounge –
Air Tightness Inspections
Finding Air Leaks
Where are the Common Air Leakage points?
Assuming you have draught proofed the windows & doors
Air flowing through and around insulation takes heat away rapidly, ruining the insulation performance. Energy Auditors take the U value calculation and reduce it by a factor of between 25 & 50% after looking at the gaps in poorly installed insulation.
If you had a hole the size of a football in the lounge –
you would fill it?

17. Air Tightness Inspections
Finding Air Leaks
Take one external door.
Around the frame to structure a 1mm gap.
This equates to a hole 70mm diameter – a tennis ball
– Multiply by 7 other openings
& there’s your football ……
And we haven’t started looking yet!
The culprits;
Cables, Waste Pipes, Ducts, Ventilation Fans, etc;
In fact at ANY point where a hole has been made in the envelope area and not sealed afterwards!
Check the waste trap behind the bath panel, see how big the hole is!
Air flowing through and around insulation takes heat away rapidly, ruining the insulation performance. Energy Auditors take the U value calculation and reduce it by a factor of between 25 & 50% after looking at the gaps in poorly installed insulation.

18. Air Tightness Inspections
Finding Other Problems
Flooring
Air Leak via Gaps in floor boards
Can you see the gaps in floor boards?

19. Air Tightness Inspections
Finding Other Problems
What’s the problem?
Missing Insulation

20. Air Tightness Inspections
Finding Other Problems
What’s the problem?
Air Leak & Thermal Bridge

21. Air Tightness Inspections
The Cost of Air Leakage
Past Air Tightness
Air Changes per Hour
Volume of Building m³
Air Infiltration Volume m³/hr
Energy required per m³/1°C ( kW) kW
Energy required m³ for average 15°C Increase kW
Energy cost £0.085/kW (Approximation)
Energy cost per 24 hours £'s
Energy cost per heating season of 120 days £'s
1950's 20
185
3700
1.30
19.43
£1.651
£39.63
£4,755.24
1990's 15
2775
0.97
14.57
£1.238
£29.72
£3,566.43
2005 10
1850
0.65
9.71
£0.826
£19.81
£2,377.62
2014 5
925
0.32
4.86
£0.413
£9.91
£1,188.81
Best Practice 3
555
0.19
2.91
£0.248
£5.94
£713.29
Passive House
0.6
111
0.04
0.58
£0.050
£1.19
£142.66
Compare the Cost.Com
1950’s House 20 Air Changes
Best Practice 3 Air Changes
Passive House Less than > 0.6 Air Changes
For NEW BUILDINGS …
(NOTE: in the above example, the calculation is just for the air leakage - we would not have the heating on 24/7 & there are other variables that would change this final calculation, which is for illustration purposes only to indicate the amount of energy used to maintain the set temperature in similar buildings with different levels of draught sealing. It does not take account of the heat transfer through walls or heat input by the occupants or other energy devices within the building & assumes the same boiler type & efficiency)
ACD – Ventilation Engineers require the Infiltration Rate – the number of natural air changes to work out the correct size for the ventilation system. The only way to provide this information ACCURATLEY is from an Air Tightness Test.
There is no way of calculating how air tight a building is.
Using Accredited Construction Details is good practice.
BUT NOTE ON EVERY ACD: “Complying with all the above checklist items will help achieve the design air permeability and may affect a reduced testing regime.”
The only way to confirm the Air Permeability or how ‘leaky’ a building is to -
Perform an Air Tightness Test !

22. SAVING YOU MONEY ALL ROUND
Air Tightness Inspections
Finding & Sealing Draughts (air leaks) is one of the ….
1. MOST EFFECTIVE
2. CHEAPEST
3. PERMANENT
Means of increasing the energy performance of ANY building!
An Air Tightness Test should be performed on ANY building where a heating system is being replaced.
WHY? – because if you stop air leaks (draughts) you won’t need as big a heating source (boiler), & especially with a Heat Pump.
Smaller Boiler,
Less Cost,
Less Energy Used,
Lower Running Costs!
SAVING YOU MONEY ALL ROUND