Infrared Thermal Imaging
Using a Infrared Thermal Imaging camera to assess the quality of my insulation
13 Jan 2010
Ian Cox-Smith, a building physicist and Mark Hearfield both from BRANZ came around to look at how well my walls are resisting heat gain/loss (keeping the heat in/out). Ian is conducting a study on retro-fitted insulation study for BRANZ. Polystyrene beads is one of the solutions he's looked at. (In fact he tested polystyrene bead insulation on his own house.)
He was particularly interested to see if there was any evidence of slumping of the polysyrene beads since Jan 2007.
When they came the temperature was 20 degrees Centigrade inside and 13 degrees Centigrade outside (we're near the end of a cold southerly snap).
They bought their FLIR P620 infrared camera which produced these images.
That's Ian in the center in white, and his reflection in the middle window. Then on the left is me standing behind the camera photographing the screen and to the left of me is Mark. Ian's elbow is measuring 24 degrees.
The reason the left window is a different colour form the middle and right side windows is it's a retrofitted double glazed unit (bought from Ultraglass in Seaview). The middle windows are standard single pane glass, and the right hand window has 3M plastic "double glazing" over it. (IR cameras do not reflect clear plastic so it doesn't see any difference.)
Ian thinks my real double glazed unit may also have a low-E coating - which enhances the IR reflection. This would be nice - I didn't choose the low-E option when I was buying because it was going to increase the price too much.
This is the corner of the lounge, just above the back french doors.
Here's what I see:
- the windows are black - that means cold
- the pelmet and curtains are yellow - which means warm, that's good
- above the pelmet you can see warm wall with faint colder vertical sections - that's the wooden studs conducting cold
- the column above the left side seems to have a section at the top that I didn't filled properly. I wonder if there's a whole in the left side stud and beads have fallen thru to the bottom of the next column?
- to the left of the french doors there a whole ceiling to floor column of cold - that's a section I left empty because there is a power socket down near the floor. The column beside it - in the corner does have insulation.
- at the top of the picture is the ceiling - all warm - that's my double layer of batts doing a good job
- along the edge of the wall and roof it's black - meaning cold. In well-constructed modern super-insulated houses the builders and architects play particular attention to this area.
- on the left side wall it look's like my insulation is a bit light. This is the first column of insulation I ever filled (with the hair dryer). It may be that the vacuum cleaner blower I used later, with it's greater velocity, does a better job at packing in the polystyrene beads than the hair dryer. Also the left side is the south wall which you'd expect would be colder (in New Zealand).
We spent 1.5 hours doing the whole house and found a diagonal bracing beam that caused me to leave some gaps.
Ian has promised to send me the images direct from the FLIR camera so I'll add those when I get them.
Other things I learnt:
- Ian used a leaf blower
- He used 16mm holes on the interior walls
- He used a good stud finder to find the studs and dwangs in his house
- Then he used the infrared thermal camera to check his work
Cheers, Paul