3.5 lb/ft³2.9 psi6" pulls STOP & CALL: K&T · vermiculite
Blue Sky Training
Blue Sky Training · presented for Colorado Springs Utilities · July 27

Dense-Pack Work Sessions

Three exercises from today's session. Nothing here is stored or sent anywhere — your answers live on your screen and vanish when you close it.

How this works: your trainer will call each exercise during the session. Work it on your phone, argue with your neighbor, and don't open the debrief panels until the room debriefs together — that's where the learning is.
WARM-UP · PAIRS · LOOK & ARGUE

Trace the Boundary

One house, three lines — and three traps drawn in. No drawing needed: look, point, argue.

House cross-section: vented crawlspace with wall insulation, two stories, kneewall half-story, cantilever bump-out, bonus room over garage
With your neighbor, trace three lines with your eyes: ① the ENVELOPE — where does inside end? ② the THERMAL boundary — where should the insulation live? ③ the AIR barrier — what actually stops airflow? Then find every place where two of your lines disagree — or disagree with what the builder installed. Three traps are drawn in.
Answer key: all three boundary lines following one aligned path around the conditioned space
  1. The crawlspace — the headliner. Batts on the walls of a VENTED crawl: a thermal boundary drawn where outdoor air flows freely, and no air barrier anywhere. Decorated. Two legal fixes, opposite directions: seal the vents and condition the crawl (the walls then carry all three lines) — or leave the vents and move both boundaries to the floor above, as the key shows.
  2. The kneewalls. Batts with open backs facing the vented attic — a sweater with no windbreaker. The key's path assumes the batt backs get air-sealed.
  3. The bonus room. Sagged floor batts touching nothing — and the boundary must wrap the room, floor AND walls, or it hangs outside its own house. This afternoon's Floor-Over-Garage section is the cure.
  4. Partial credit: the cantilever. A floor hanging in outdoor air needs its underside wrapped and sealed — or it's a cold shelf with carpet on it.
EXERCISE 01 · PAIRS · 10 MIN

Pack It or Walk?

Ten scenes from real jobs. Tap a verdict, then write one line: why — and who fixes it.

S-01 · BASEMENT WALKTHROUGH

Ceramic knobs and cloth-covered wire run along the basement joists. Upstairs, every receptacle is a modern three-prong and the panel has breakers.

S-02 · FIRST PROBE OF THE DAY

Your probe comes back out of the drill hole with silvery-gold, pebbly granules stuck to it. They pour out of the hole like lightweight gravel.

S-03 · THE BIG GRILLE

An exterior wall carries a large grille with no damper. You set the air handler to fan-on and hold a tissue to it — the tissue snaps flat against the grille and stays.

S-04 · THE PUSH TEST

Pre-war plaster wall. Flat hand on the field: it flexes and feels spongy, and there's a spiderweb of fine cracks radiating near the ceiling corner.

S-05 · THE RANCH

1958 ranch, vinyl siding, empty 2×4 walls confirmed by borescope, dry cavities, no stains, panel and wiring updated with documentation, nothing on the walkthrough flags.

S-06 · KITCHEN WALL

The kitchen sink sits on an exterior wall. Under the cabinet, the trap arm disappears into that wall, and the vent stack exits the roof directly above.

S-07 · THE FOAM WALL

The "stucco" sounds hollow when you knock. A corner chip reveals a thin synthetic coating over rigid foam board. No weeps, no drainage details anywhere.

S-08 · BRICK WITH WEEPS

Brick exterior with open weep holes along the bottom course. Interior side is drywall over studs — the borescope shows an empty framed cavity behind the interior finish, then a gap, then the brick.

S-09 · UNDER THE WINDOW

Brown tide-line stain on the drywall below a window, a musty smell in the room, and your moisture meter reads 24% in the framing at the sill.

S-10 · GARAGE CEILING, 1974

FOG job in a 1974 home. You look up before cutting your strips: the garage ceiling has a heavy knockdown texture across the whole surface.

  1. STOP & CALL. Attic or basement K&T means assume the walls — new outlets prove nothing. Becomes defer the moment the licensed electrician is engaged; you resume only against a written dead-or-removed certification.
  2. STOP & CALL. That's vermiculite — assume asbestos, don't disturb, don't vacuum. The home defers until licensed abatement is documented.
  3. NOT A CANDIDATE — that bay. The tissue proved a live cavity return. Never fill it; seal what the grille reaches, refer to HVAC for a real duct, document. The rest of the wall can still pack.
  4. DEFER. The keys are gone — blower pressure will bulge or blow that plaster off the lath. Plaster washers / stabilization or refinish first.
  5. PACK ON. The bread-and-butter job. Probe every hole anyway — the walkthrough earns you the right to blow, not to skip discipline.
  6. PACK ON — with the pipe rules. Predict the DWV from the fixture and stack, probe gently, move holes to miss it, and insulate the cold side only so house heat still reaches the trap.
  7. NOT A CANDIDATE. EIFS — face-sealed synthetic stucco over foam. Fill it and that wall loses its last drying path. Walk away.
  8. PACK ON — the stud bay only. Veneer brick over framing: fill the framed cavity, never the drainage gap, weeps stay clear. Mortar-joint access or interior blow.
  9. DEFER. Active bulk water + 24% MC disqualifies the wall today. Flashing fix, dry-down, re-check — then it's a fine candidate.
  10. DEFER — test or assume. Pre-1981 + texture across the whole overhead + ~50 SF of strip cutting is the one place in this scope where asbestos test-or-assume is the rule. Smooth fire-taped board would have been seam-mud only — single digits of square feet — proceed with wet + HEPA.
EXERCISE 02 · PAIRS · 8 MIN

The Violation Hunt

One crew, one morning, twelve mistakes. Read the ticket. List every violation you catch.

JOB TICKET · MONDAY 7:45 AM · 1948 BUNGALOW, WOOD SIDING

Jake's crew rolls up and starts unloading. To save setup time, Jake skips the interior walkthrough — "we've done a hundred of these" — and the crew starts pulling siding on the north wall. Marcus runs a forty-foot hose off the machine and necks the three-inch line straight down to the fill tube with a single reducer. The machine is still on Friday's attic settings — gate wide open — and nobody runs the calibration box because "we know this machine."

In the basement, Jake spots cloth-covered wire on ceramic knobs. He touches his voltage pen to it — no beep — flips the breaker labeled "bedrooms" off, and tells the crew they're good to blow for the day. Upstairs, the crew drills the wall behind a big return grille and packs the bay tight. On the second bay, the machine starts to labor, so Marcus pulls the tube out and moves to the next hole — "she was fighting me."

Mid-morning, cellulose starts drifting out of a soffit. Marcus sprints to the machine and slaps the AIR off. Meanwhile on the south wall, three asbestos-cement shingles crack as Danny pries them with a flat bar. "Only three," he says, and keeps prying. Before lunch, Jake wants a density check, so he pulls a core six inches from a fill hole. It weighs light, which he figures is fine. In the garage, the crew patches the strip they cut from the ceiling under the kids' bedroom with a leftover piece of half-inch regular drywall — "drywall is drywall."

  1. Skipped the walkthrough — fifteen minutes of eyes-open walking prevents every disaster in this trade.
  2. Forty-foot hose — never under fifty; short hose sends slugs, slugs clog.
  3. One abrupt reducer — gradual steps: 3 → 2.5 → 2 → tube.
  4. Attic settings on a wall — gate to ~¼, air near max. Wall work is air-heavy.
  5. No calibration box — 2 ft³ + 7 lb proves the setup before the wall does.
  6. Pen tester "cleared" K&T — pen testers false-read on this wiring; it is not the crew's call.
  7. Breaker-off as the fix — the standard is a licensed electrician's written dead-or-removed certification. The house gets re-energized at five o'clock.
  8. Packed the return bay — big grille = tissue test first; a live cavity return never gets filled.
  9. Quit at the machine's struggle — the struggle IS the product. Pull six inches, keep packing, and finish the down-leg.
  10. Blowout: killed air first — material off first, then air, or you strand a slug in the line.
  11. Broke transite and kept going — we don't "be careful," we count: ~2 SF per shingle against the 32-SF trigger, and the right answer was never a flat bar.
  12. Core six inches from a fill hole — cores come from undisturbed wall, two feet or more from any hole; next to the hole always reads light.
  13. Half-inch regular board on the garage ceiling — under habitable rooms the separation is 5/8" Type X, fastened on the code schedule, edges blocked. Bonus catch if you flagged the missing fire-taping.

Twelve planted — thirteen if you caught the patch two ways. Any crew that finds ten is running a better Monday than Jake.

EXERCISE 03 · ROLEPLAY · 2 MIN PER CARD

Kitchen-Table Objections

One of you is the homeowner — read the card with feeling. One of you answers. Swap every card. Coach's angle opens after you've tried.

CARD 1 · THE SKEPTICAL NEIGHBOR
"My neighbor says blowing insulation into old walls causes mold. He saw it on the internet."
The neighbor is half-remembering something real: wet walls and insulation don't mix. Agree with the physics, then reframe: "He's right that a wet wall should never be packed — which is exactly why we inspect for leaks first and walk away from wet walls. Dry wall, packed right, actually gets warmer surfaces — and warm surfaces are where condensation and mildew stop."
CARD 2 · THE WINDOW SHOPPER
"Shouldn't we just replace the windows first? That's what everyone does."
Walls are usually five-plus times the area of windows and often leakier per square foot. Don't trash windows — sequence them: "Windows are a fine someday project. But your walls are most of your house's skin, and for a fraction of window money we can make all of them warm and tight this week."
CARD 3 · THE WORRIER
"If you drill into my walls, aren't you going to stir up asbestos?"
Take the concern seriously — it's the right instinct in the wrong place. "Good question, and it's exactly what our walkthrough is for. The materials that matter get identified before any drill comes out — and if we find the ones that stop a job, we stop the job. Small holes with dust control at the bit is a very different thing from demolition."
CARD 4 · THE OLD-TIMER
"Houses need to breathe. You'll seal mine up too tight."
Separate the two things "breathe" means: "You're right that a house needs fresh air — for the people, on purpose, through ventilation. What it doesn't need is random cold air through the walls, which is just a heating bill. We tighten the accident and, where needed, plan the ventilation."
CARD 5 · THE RESEARCHER
"I read that blown insulation just settles and stops working after a few years."
True for loose fill, defeated by density: "That's real — for insulation poured in loose. Dense-pack is installed under pressure to a density where it holds its own weight forever. That number — 3.5 pounds a cubic foot — is the whole difference, and it's what gets verified on our jobs."
CARD 6 · THE ACCOUNTANT
"What's the payback? Give me a number."
Give honest ranges, then widen the ledger: heating savings are real but house-specific; the rebate cuts 40% of the cost up front; and comfort pays daily — "the room you don't use in January becomes a room again." Never invent a precise payback you can't defend.
CARD 7 · THE HOUSE-PROUD ONE
"You want to drill holes in my plaster? It's original 1926 plaster."
Respect the plaster out loud, then show the plan: exterior access if possible; if interior, holes hidden low behind baseboards or in closets, grit hole saws, and an honest patch conversation — "a plaster patch is a repair, not a magic trick; it takes paint to blend, and we agree on all of it before a drill comes out."
CARD 8 · THE WEEKEND WARRIOR
"The rental place has a blower. Why wouldn't I just do this myself?"
Don't mock the machine — name the difference: "That rental blows attics fine. It can't build the pressure a wall needs — dense-pack takes about 2.9 psi and a technique with a rhythm to it. Done at half density it settles, and nobody can see that until the wall is cold again."
CARD 9 · THE TAX PLANNER
"So I'll get the 30% federal tax credit too, right? I saw it online."
Say it plainly — half the internet is out of date: "That federal credit ended December 31, 2025 — work done this year doesn't qualify. What's real right now is the utility rebate: 40% back, up to $1,250 on walls, and a dense-packed 2×4 wall lands right at the R-13 the rebate requires."
CARD 10 · THE FRUSTRATED ONE
"An electrician? A rewire? I hired you to blow insulation, not spend my money."
Hold the line warmly: "I can't legally or safely bury live knob-and-tube — that's state code, not my preference. Here's the other half: insurers surcharge or drop homes with live K&T, so the electrician's letter protects your coverage, not just my job. We insulate the day that letter exists."
CARD 11 · THE LOYALIST
"My uncle installed fiberglass for thirty years and says cellulose is junk."
Never fight the uncle — recruit him: "Fiberglass dense-packs too, with the right rated product — your uncle's trade is legit. We run cellulose because it edges fiberglass on air-sealing in head-to-head tests and it buffers moisture in old walls, which is why the cold-climate programs default to it. Same physics either way: density is what matters."
CARD 12 · THE ALARMED ONE
"You STOPPED? What do you mean you found something and stopped working on my house?"
The walk-away speech, said with pride: "We found vermiculite insulation, and the safe assumption is that it contains asbestos. Sealed up and left alone it isn't hurting anyone — but disturbing it would be. Stopping is what protects your family and my crew. Here's the photo, here's who handles it, and here's what happens next."
Card 1 of 12
FIELD TOOLS · USE THEM ON REAL JOBS

Calculators

The three pieces of dense-pack math, ready for the tailgate. Nothing is stored or sent.

Bag Order

A 25-lb bag at 3.5 lb/ft³ makes about 7.1 ft³ of packed insulation. Spread 3.5 inches deep, that covers ≈ 24.5 SF. The coverage chart is the density target wearing different clothes — chart, calibration box, and bag count are one fact in three costumes. Always use the chart number for your product and cavity depth.

Core Call

Density = weight ÷ volume. The core volume is π × (dia ÷ 2)² × depth. At a 4-inch core in a 2×4 wall, 3.5 lb/ft³ ≈ 40 g — which is why the field rule is "about forty grams." Core at least 2 ft from any fill hole; cores are escalation, not routine QC.

Calibration Box

Run it at job start, at every material change, and after a big humidity swing. The box proves your machine-and-hose setup before the wall does it for you.
SELF-CHECK · 15 CALLS

Myth or Fact?

Tap your call. Instant verdict, one-line why. Your score follows you to the bottom.

0 / 0 answered
FIELD RESOURCES · PRINT OR SAVE

Take-Home Kit

The printed handouts from today's session — same versions, yours to keep, reprint, and put on the truck.

PDF · 2-UP CARDDense-Pack Field CardThe numbers on one card: 3.5 · 2.9 · 6-inch pulls, bag math, stop-and-call triggers, QR links to the rebate page and DOE's RED Calc. PDF · 1 PAGEThe Walk-Away SheetNineteen triggers in three tiers — stop-and-call, defer until fixed, not a dense-pack job — each with who fixes it. PDF · 2 PAGESTruck Materials ChecklistRoughly ninety checkboxes across ten categories — everything a dense-pack crew loads before rolling. PDF · 2 PAGESChecklist CompanionThe same list with one line per item on what it's for — the why behind the what, for training new crew.