Blower door and airtightness in Heinsberg
Blower door Heinsberg: the test measures what was built
A blower door test shows within hours how tight a building really is. It cannot be passed after the fact. It is decided on site, at every joint, every junction and every penetration. That is exactly what MK-AUSBAU works on.
- Test pressure
- 50 pascal
- Value
- Air change rate n50
- Our part
- Building the airtight layer
- Area
- Kreis Heinsberg
01The test
What happens during a blower door test
A fan is fitted airtight into a door opening and creates a pressure difference of 50 pascal between the building and the outside air. The volume of air it has to move equals the air passing through every leak in the envelope.
Windows and external doors are closed, internal doors opened, ventilation openings sealed. The building is treated as one single volume of air.
The fan draws air out of the building. Outside air flows in through every fault, and the cold draught becomes noticeable at the junctions.
The direction is reversed. Air is now pushed from inside outwards, which reveals some leaks more clearly than depressurisation does.
The air flow at 50 pascal and the internal volume give the air change rate n50, expressed in air changes per hour.
NoteThe values come from the test report and describe the state of the building on the day of the measurement.
02Who tests
Who needs a test
Not every building has to be tested. The evidence becomes compulsory as soon as a funding programme or the ventilation design calls for it. Those who test voluntarily usually do so because faults can only be fixed expensively afterwards.
Funding programmes regularly require evidence of airtightness as part of the confirmation issued after the work is done.
A ventilation system with heat recovery only works in a tight envelope. Without one, the recovered heat leaves again through the joints.
A funded refurbishment also leads to a test as a rule, because the calculated energy demand is otherwise unsupported.
A more favourable assumption in the energy balance is only permitted where the tightness of the building has actually been tested.
A test at shell stage, before anything is boarded over, is the only chance to reach a fault without taking work apart again.
- Without ventilation system
- n50 up to 3.0 per hour
- With ventilation system
- n50 up to 1.5 per hour
- Passive house
- n50 up to 0.6 per hour
NoteWhich value applies to your building depends on the method of evidence and on the funding programme. What is binding is always what your own calculation says.
03Leaks
Where a building loses air
Leaks almost never sit in the middle of a surface. They sit where two components meet, where something is led through the envelope, and where somebody opened things up again later.
NoteThese photographs show building situations, not reference projects.
04Services
What MK-AUSBAU does to the airtight layer
We work on the layer itself: on the membrane, the tape, the perimeter joint and the board over it. That is the work a test result rests on in the end.
Vapour control membrane, dust barrier and taped board materials as one continuous layer, matched to the component and to the moisture and airtightness concept.
A continuous layerTransitions to masonry, rafters, window frames and the ground slab, together with grommets for pipes and cables.
A tight transitionNatural insulation such as straw and conventional materials such as glass wool, always planned together with the moisture and airtightness concept.
A build up that suitsStud frame, boarding and filling carried out so that the layer behind it stays undamaged.
An undamaged layerOpen up, tape properly, close again. Wherever a fault has been named in the report.
A closed faultA check of the site before the test date, so that obvious faults never make it into the measurement.
A known positionNoteThe measurement itself is not part of what we do. It is carried out by an independent test team.
A few sentences are enough for a first assessment.
05Preparation
How a building is prepared for the test
A test date is not a surprise inspection. What counts on the day is built in the weeks before it and checked in the hours before it.
Which stage of construction is to be tested. At shell stage a fault can still be reached, in a finished house only the result counts.
Client and designerWindows and external doors shut, internal doors open, shutter boxes and inspection hatches closed.
Site managementVentilation outlets, extract ducts, flue connections and drains are prepared so that they do not enter the measurement as leaks.
MK-AUSBAUOne last round at the junctions and penetrations. Anything found now still costs almost nothing.
MK-AUSBAUThe test is placed within the construction programme, so that no trade opens up again what has just been made tight.
Everyone involvedNoteAnyone running cables after the test changes the result. That is why the date belongs in the programme rather than beside it.
06Findings
When the test is not passed
A value that is too high is not a disaster, it is a list. The test team names where air is moving. Everything after that is craft.
A fault costs minutes at shell stage and a whole day once the fit out is done.
Overlaps and butt joints are opened, cleaned and permanently bonded with the right tape.
The junction to masonry or concrete is made on a sound substrate with adhesive or a purpose made collar.
Pipes and cables are given a proper grommet instead of a wrap of tape.
Tears and holes are taped over generously or the bay is replaced. Nothing is patched.
The board is opened, the layer is made good and the opening is closed and filled properly again.
NoteOnce the repair is done the building can be tested again. Whoever issues the evidence decides on that.
07The firm
The firm
MK-AUSBAU is an interior fit out and refurbishment business in Heinsberg. Maxim Kelm has run it since 2016.
The firm comes from drywall and insulation work. Both trades help decide whether an envelope becomes tight, and both are examined by a measurement in the end.
We work in Kreis Heinsberg and the surrounding area. Short distances mean that a fault reported today does not wait until the week after next for an appointment.
We say in advance what we take on and what we do not. The measurement belongs to an independent test team, so that the work and its examination stay apart.
- One contact from the first enquiry to handover
- Written quotations that name the build up
- Dates that fit the construction programme
- A clean site, every evening
- Based in
- Heinsberg
- Since
- 2016
- Trades
- Drywall and insulation
08Area
Where we work
Our focus is Kreis Heinsberg. On this kind of work a short journey mostly means one thing: a date can be moved at short notice when another trade on site needs longer.
Towns we work in
- Heinsberg
- Hückelhoven
- Erkelenz
- Geilenkirchen
- Wassenberg
- Wegberg
- Übach-Palenberg
- Gangelt
- Selfkant
- Waldfeucht
And beyond
For larger projects we also travel to Mönchengladbach and Aachen. Just tell us where the building is.
NoteThe journey is stated in the quotation and is never charged afterwards.
09Questions
Common questions
What clients most often want to know before the first appointment.
01Does MK-AUSBAU carry out the measurement itself?
No. We build and repair the airtight layer and prepare the building for the appointment. The measurement is carried out by an independent test team with its own equipment.
02When is the best time for a test?
As soon as the airtight layer is finished and still accessible. Before the boarding goes on, a fault can be fixed in minutes; afterwards only by taking work apart.
03How long does a blower door test take?
That depends on the size of the building and how accessible it is. For a detached house half a day is usually allowed, including preparation and leak detection.
04What does a measurement cost?
That is set by the test team, not by us. What we can price is the work on the airtight layer, and for that you get a written quotation naming the build up.
05Does an older building have to reach the same values?
Not necessarily. Which value applies depends on the method of evidence and on the funding programme. A refurbishment is often assessed against a different value than a new build.
06What happens if the value is too high?
The test team locates the leaks and records them. We open the affected places, make the layer good and close them again. The building can then be tested once more.
07Is a vapour barrier enough for airtightness?
Not automatically. What matters is a continuous, properly taped layer. A membrane that is not connected seals nothing and, laid badly, can even do harm.
08Do you work outside Heinsberg as well?
Yes. Our focus is Kreis Heinsberg. For larger projects we also travel to Mönchengladbach and Aachen.
10Enquiry
Send an enquiry
Tell us briefly which building this is about and when it is to be tested. We will come back with an assessment and a proposed date.
- Telephone
- +49 (0) 2452 8607038
- info@ausbau.nrw
- Address
- Am Diebsweg 17, 52525 Heinsberg
- Working area
- Kreis Heinsberg
This helps us give you a first answer
- New build or existing building
- Stage of construction and planned test date
- Approximate heated floor area
- Mechanical ventilation planned or installed
- Funding programme, if one is running