Install Blown-In Attic Insulation

A. Finished-Project Specification

Deliverable: the complete attic floor area identified in the insulation schedule, covered with loose-fill insulation at the target settled depth stated in the schedule, installed using at least the minimum bag count from the manufacturer coverage chart, with soffit ventilation, baffles, heat-source clearances, access dams, and equipment platforms preserved, and a completed installation record with depth readings, bag count, and coverage photographs.

B. Component and Quantity Schedule

Item	Quantity	Source	Placement	Preparation
Loose-fill insulation	Per coverage chart for attic area and target depth	Approved insulation schedule	Distributed evenly across the attic floor	Fed into blower machine at controlled rate
Depth markers	Per grid spacing stated in schedule	Approved insulation schedule	Installed at grid points before blowing begins	Marked clearly at target settled depth
Insulation dams	One per eave, access opening, and restricted clearance zone	Chapter 6 baffle work and this chapter's clearance requirements	Eaves, attic access, mechanical platforms, heat-source zones	Built to full height of target depth before blowing

C. Acceptance Standards

Check	Standard
Settled depth	Representative depth readings across the attic meet or exceed the target settled depth stated in the schedule
Product quantity	Installed bag count meets or exceeds the minimum calculated from the approved coverage chart
Coverage uniformity	No bare areas, no piles that leave adjacent areas under target depth
Ventilation clearance	Soffit vents and baffle channels remain open and unobstructed after installation
Heat and access clearance	Recessed lights, chimneys, flues, fans, electrical equipment, and access points remain at their required clearance and are not buried
Documentation	Depth readings, bag count, product lot, and coverage photographs are recorded on the installation worksheet

D. Preparation — Schedule Review and Attic Readiness

1. Review the insulation schedule, product coverage chart, bag count, target settled depth, density, attic area, access, and manufacturer instructions. Confirm the product identified in the schedule matches the material staged for installation before opening any bags.
2. Confirm that the attic is dry and that roof leaks, air leaks, bypasses, ventilation baffles, electrical hazards, and heat clearances have been resolved. Walk the attic and visually confirm the Chapter 5 bypass seals and Chapter 6 baffles are intact for the area to be insulated.
3. Confirm that required rough and air-sealing inspections are complete. Review inspection records for this attic area before proceeding; do not blow insulation over an area awaiting a required inspection.

E. Access, Markers, and Dams

1. Establish attic walk paths, lighting, communication, and fall-through protection. Confirm walk boards are positioned across joists along the planned travel route before any material is staged.
2. Install depth markers at the required grid spacing and mark the target depth. Use a tape measure to place markers at the schedule's specified spacing and mark each one clearly at the target settled depth.
3. Build durable dams around attic access, storage paths, mechanical platforms, recessed-light clearances, chimneys, flues, and equipment. Build each dam to the full target depth before blowing begins so it will not be overtopped once material is installed.
4. Protect soffit vents and baffles from blockage. Visually confirm each Chapter 6 baffle is in place and undamaged before the area behind it is filled.
5. Mark junction boxes, valves, dampers, and service points that must remain accessible. Flag each with a visible marker taller than the target insulation depth.

F. Quantity Calculation and Equipment Setup

1. Calculate the minimum product quantity from the approved area and coverage chart. Multiply the attic square footage by the chart's bags-per-square-foot value for the target depth and record the result on the worksheet.
2. Record starting bag count and product lot information. Log the lot number before staging bags so all installed material can be traced.
3. Inspect blower machine, hose, power supply, guards, and controls. Confirm the hopper guard is in place and the hose couplings are secure before starting the machine.
4. Assign one trained operator at the machine and one installer at the hose. Confirm both crew members understand the planned distribution route before starting.
5. Establish communication and emergency-stop signals. Test the radio or intercom connection and agree on a stop signal before the machine is started.

G. Distribution

1. Feed material into the machine at the controlled rate. Follow the manufacturer's stated feed rate for the product; do not overfeed the hopper.
2. Begin at the farthest attic area and work back toward the access. This keeps the installer's exit path clear of freshly blown, uncompacted material.
3. Hold the hose at the specified angle and distance to distribute material without creating piles or bare areas. Sweep the hose in overlapping passes rather than holding it stationary over one spot.
4. Maintain consistent coverage around framing, braces, ducts, and irregular spaces. Direct material into corners and around obstructions deliberately rather than relying on overspray to reach them.
5. Do not bury required access points or damage duct insulation. Confirm marked access points remain visible above the fill line as work proceeds.
6. Check depth against markers during installation. Stop periodically and read several markers before continuing to the next section.
7. Track actual bags installed. Log each bag as it is fed into the machine so the running total can be compared to the calculated minimum.
8. Correct low areas without excessively overfilling adjacent areas. Return to any area reading below target depth and add material specifically to that area.

H. Verification and Closeout

1. Inspect ventilation channels, heat clearances, access dams, equipment platforms, and walk paths. Confirm baffles are still open, dams are intact, and all flagged access points remain visible.
2. Verify final depth and product quantity. Confirm the installed bag count meets or exceeds the calculated minimum and that representative depth readings meet the target across the attic.
3. Record representative depth readings and coverage photographs. Photograph markers at several locations along with overall coverage views.
4. Clean equipment and occupied areas using controlled dust procedures. Vacuum tracked material from walk paths and the attic access before leaving the site.
5. Complete the attic-insulation inspection before closing access. Finalize the installation worksheet with depth readings, bag count, product lot, and photographs before securing the attic hatch.