Ceiling Insulation - Cost-Effective


Ceiling insulation is one of the most cost-effective energy efficiency measures. The easiest part of the exterior building envelope to insulate is the attics over flat ceilings. Usually, they are accessible and have ample room for insulation.

Today’s homes, however, use cathedral ceilings or have attic walls that present unique insulation requirements. It is always important to insulate all types of ceilings properly.

Insulating the attic

When planning and managing attic insulation projects, certain things have to be ensured about their status and checked first. You need to make sure that all air leaks through the top floor ceiling are completely sealed. You also need to ensure that insulation levels must meet or exceed local building codes.

There should be space that is provided for both insulation and air flow from the soffit vents at the eaves. You have to ensure that the insulation coverage is continuous.

The attic area intended fro storage have enough space underneath for full insulation value. The attic access doors should be insulated and sealed and the knee wall areas have adequate insulation and an air sealing barrier.

Some insulation techniques

Loose-fill or batt insulation is typically installed in an attic. You need to put the backing next to the ceiling finish for batts with attached vapor retarders.

Installation costs can vary, but blown-in loose fill attic insulation (fiberglass, rock wool, or cellulose) is usually less expensive than the batts. They also provide better coverage.

Installing loose-fill insulation

First, you need to seal all attics to home air leaks, especially chases, bypasses, and furr-downs. Most insulation like fiberglass and rock wool does not stop air flow.

Second, you need to follow clearance requirements for heat-producing equipment found in the attic like flues, or exhaust fans. The other blocking requirement might be mandated by local building codes. You can use metal flashing, plastic or cardboard batt files or pieces of batt or rigid insulation for blocking.

Install rafter baffles to preserve ventilation from soffit vents at eave of the roof. Use insulation dams at the soffit, porch, and garage and attic access to ensure full coverage and reduce spillage.

Insulate over the attic access by attaching a piece of batt insulation. Obtain complete coverage of the insulation at consistent depths. Have attic rulers to show proper blown depth.

Installing batt insulation

Seal all attic to home air leaks, especially chases, bypasses and furr-downs. Insulation like fiberglass and rock wool does not stop air flow. Block around heat-producing devices. It is important to cover the top of ceiling joints or bottom cord of truss with insulation.

Get the complete coverage of full-thickness, non-compressed insulation. When installing the batts, be sure they completely fill the joist cavities. Shake betts to ensure proper loft. If the joist spacing is uneven, patch the gaps in the insulation with scrap pieces. Never compress the insulation with wiring, plumbing or duct work.

The R-19 cathedral ceiling insulation for some house designs, depending on the climatic zones.  In most areas, R-25 and R-38 insulation is recommended.

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