There are certainly certain items I would suspect are
considered standard and then other areas where it becomes an owner’s preference
choice.
Obviously minimum “Thermal Requirements” standard.
Roof Unvented over AC – R20
Exterior Wall – R5
Garage common Wall – R11
Basic sound attenuation at laundry, baths and mechanical
closets where applicable.
Upgradable Options include interior sound walls, between
floor sound solutions and insulating non conditioned areas such as garages,
porches and loggias.
Choices:
Exterior wall:
Rigid Board – R5 - I only consider this a viable choice if
glued to wall prior to framing and seams taped to provide continuous
envelope. Generally, $1.00+.
Options: Because air space provides improved R-Value a chase wall 1 5/8” offer
an R5 with basic AA2 foil or R7 with VR-Plus foil. These choices are
approximately only 35% and 55% respectively of the price of Rigid Board with
same or better result.
There are two other options: Core Foam 500 (CBS block fill injection) – I’m not
a super fan but paperwork claims an R9+. The Ultimate choice is use of
Closed cell foam. Expensive but advantage beyond R-Value includes an
absolute continuous air barrier, flood control, exterior sound. Expensive
choice and requires proper care by framers to add clips or cross bars to
stabilize framing.
Interior walls: Sound reduction and prevention is very much
an assembly consideration. For our purpose we will presume interior walls
with only one 3 5/8 metal stud.
Options:
Standard Batt – better than nothing, carries a tested result of STC in high
forties. .47
Mineral Wool – (Roxul brand is the crème de la crème) doubles the STC
values. Recommended for certain around theatres. An optionable
upgrade for any walls, such as bedrooms, baths and others. 2x price of
Sound Batt. When working with multimillion-dollar projects, this tends to
be considered a low-cost improvement no customer has regretted. These
owners have always been pleased they did not overlook this upgrade. Open
Cell foam is a comparable choice, but the testing reports do not exceed the
Roxul and this requires added coordination.
Between Floors Sound: A real conundrum as I like to claim,
“Sound is in the ear of the beholder”. No customer guarantee offered. 😊
Options: These can be used in
conjunction or singularly.
Icynene – a fantastic choice to encapsulate interior sound a prevent resonance.
If lots of stone and tile being used and music speakers throughout the home, I
believe this should be considered. This is NOT considered a great
solution to prevent thumping or walking from above.
Sound Batt or Roxul – same
discussion from above but note the assembly of floor system (recommend a rubber
matting above), air space, these products and drywall is likely as good as one
can do in thumping prevention.
Unconditioned spaces: (exterior porch, unconditioned garage
…)
Whether foam or batt makes no difference. Both slow down some heat
transfer but space will be nominal to the outside conditions. Foam is
cleaner and allows no to interfere with lights or speakers installed as bottom
chord. Doing nothing is standard.
We have all passed the Introductory 2nd level
course Insulation 202 by Therma Seal University. 😊
Send questions or comments if presentation has been less
than clear. Happy Memorial Weekend!
