CMHC Comparison of Under-Floor Insulation Systems - PDF File

Understanding Bubble Foil Insulation

The Bubble Bursts, The New Hydronics V3 I6 - By Simon Blake - PDF File

Excerpts from the The bubble bursts
CMHC study compares underslab insulation materials
By Simon Blake

A new study on underslab insulation conducted by the Canadian Mortgage and Housing Corporation)
(CMHC has confirmed what a lot of people in the hydronic heating industry have suspected.

The floor we tested with bubble foil underneath did not look like it had any insulation underneath,
reported Don Fugler, senior researcher in the CMHC policy and research division.

In fact the report left no doubt about how bubble foil performed:
Bubble-pack insulation showed performance that was similar in nature to an uninsulated floor.
There was little temperature difference between the inside of the basement and the
ground below, the ground temperature varied with indoor temperature, and the ground under the
insulation was warmer than expected for undisturbed deep ground temperatures,' said the report.

Fugler noted that he has seen manufacturer's claims of as high as R-15 for bubblepack.
The message, he added, is that the contractor should not accept a manufacturer's claims
if they cannot provide independent verification for their test results.

As for bubble foil as an underslab insulation:
If you want to use it instead of six mil poly, that's okay, he laughed.

Charts from the: CMHC Comparison of Under-Floor Insulation Systems


The bubble-pack insulation had a low insulating value compared to the
polyurethane panels and the XPS board.
It's cost benefit was the poorest of all insulating materials tested.


The more common 50 mm of extruded polystyrene insulation had an
RSI value similar to published data for the material.
A cost-benefit analysis suggests it is a better option than the bubble-pack insulation.