Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 1692 visits
Although this seems to be true, this is a dangerous generalization. There are many factors that govern airtighness of round ductwork, including roundness (any slight ovality can cause leakage at ...
Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 1601 visits
This is generally not possible. In systems with good airtightness, the leakage flow rates are too small for one to be able to accurately measure the flow rate over the fan.
Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 1908 visits
In general, yes. For more information you can check-out the Information Paper P187 “Duct System Air Leakage — How Scandinavia tackled the problem” by P.G.Schild & J.Railio, on the BUILDUP website
Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 1743 visits
It is not presently mentioned in CEN standards. Other countries might be using the same default level as France in their energy performance calculation standards, but there is no reason to ...
Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 1514 visits
Sweden does not use its building regulations to impose its strict requirements on ductwork airtightness. Rather it is a voluntary trade standard (the AMA VVS specifications) that has driven the ...
Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 1223 visits
The reason for this is twofold:
(1) When one uses only one test pressure, then the test results can be expressed with just one number, the “flow coefficient”. This is very simple and ...
Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 1329 visits
The reason for this is twofold:
(1) When one uses only one test pressure, then the test results can be expressed with just one number, the “flow coefficient”. This is very simple and ...
Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 2385 visits
It is important to use the correct type of screw or rivet. Avoid screws with a wide drill tip (which drill a hole in the duct wall) and blind pop rivets (which are not airtight because the inner ...
Answered by Peter G. Schild, SINTEF Building & Infrastructure
Answered on 16 December 2009
Visits: 1425 visits
In Sweden, according to the trade guidelines VVS AMA, on-site pressure tests need only cover 10% of the duct surface area round ducts, and 20% for rectangular ducts. Denmark has similar rules. ...
