Insulation values provide some indication of the efficiency of a home. However there are other factors. If air leaks through the fiberglass is makes a great filter but the R-value drops to 3-4. It also can contribute to condensation in the walls and attic.

Thermal bridging ( heat transfer to cold through a material)  - Studs have an insulation value of 1.2 per inch so each stud value is only R-7. If you have a 3 ply 2X6 post supporting your roof inside a closet, and the closet is closed during cold weather you could expect to see frost on that wall. Sometimes if you pile things up against that wall and the warm air cannot access it, it will actually freeze to the wall.

Don't pile things against exterior walls
Do keep closet doors open

Adding exterior insulation is always a good option. You increase the house warmth, reduce thermal bridging, but better yet, you decrease the risk of condensation and frost inside the wall. 

Different material are available for insulating your home

Current Code minimum
Currently the minimum required insulation levels for new homes built to current Alberta Building Code are as follows:
(Nominal rather than effective) 

  • Exterior walls R-12 
  • Cantilever floors ( including bonus rooms) R-20
  • Attics R-34
  • Basement walls R-8

Most new homes generally use 
  • Exterior walls R-19
  • Cantilever floors ( including bonus rooms) R-28
  • Attics R-40
  • Basement walls R-12

By the way - in 2013 the building code proposals will  increase energy requirements and ratings will be in the R-22 effective range for walls ( nominal about R-24-26) 

Using a nominal R-19 fiberglass batt insulating and building with 24 inch on centre spaced studs provides an effective R value of about R-17 while 16" on centre spacing is around R-16.  ( depending on how much solid lumber thermal bridging is in a wall) 

Mineral wool batt insulation
Mineral wool insulation provides sound barrier and better insulation value as well as being fireproof. 
  • 5 1/2" wallNominal R-22 ( effective R 20.5)

You can also blow insulation into the walls
R values are an effective R-20 to R-22

  • Average dual glaze windows are about      R-2
  • add Low E and argon                              R-3
  • Triglaze Low E argon                       R- 6 

Attics have several options
  • Fiberglass batt
  • Fiberglass blow-in
  • Cellulose blow-in

Spray Foams
Spray foam insulations come in 2 main varieties

  • Closed cell - 2 pound density -  acts as vapour barrier, air barrier, insulation  R- 6/7 per inch
  • Open cell - 1/2 pound density -  acts as air barrier, insulation (requires vapour barrier) R-4 per inch

Very air tight if you also seal the framing connections ( studs to plates, between plates, etc.)


2 pound density closed cell spray foam

WALLTITE Spray Foam is air tight & vapour tight

R-14 Mineral Wool batt over exterior 2" Styrofoam provides a 6" wall with effective  R-27.5

BIBS ( Blown-in Blanket) or Spider Insulation is blown into spaces behind a net that is attached to the wall or ceiling

Fiberglass blow-in attic insulation

Fiberglass friction fit batt insulation

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