WEATHERIZATIONFOR MULTIFAMILY BUILDINGS

A complete envelope upgrade for your 3+ unit building, often at zero out-of-pocket cost. Weatherization combines insulation, air sealing, and duct sealing into one fully rebate-funded project. Income-eligible buildings frequently qualify for 100% coverage through the Nicor Gas weatherization program.

THE COMPLETE BUILDING ENVELOPE UPGRADE

INSULATION WITHOUT AIR SEALING UNDERPERFORMS EVERY TIME

The Nicor Gas weatherization program funds eligible multifamily buildings at up to 100% of project costs. We are an authorized contractor for this program and one of the few in Illinois qualified to deliver it. For market-rate buildings that do not meet income-eligibility, ComEd, Nicor energySMART, Peoples Gas, and NorthShore Gas typically cover 60-90% of the project cost through standard rebate programs.

Weatherization is the industry term for a comprehensive set of improvements that reduce uncontrolled energy loss through your building's envelope. It is not a single product. It is a coordinated package of insulation, air sealing, and duct sealing measures, delivered together to maximize building performance and rebate eligibility simultaneously.

What We Seal in Multifamily Buildings

Insulation, attic floor, walls, basement, and rim joists

Air sealing, every leak point in the envelope addressed

Duct sealing, conditioned air delivered where it belongs

Pre and post blower door testing, measured improvement documented

Full rebate paperwork handled, from pre-approval to final submission

One coordinated project, one contractor, one timeline

100% coverage available for income-eligible buildings

— THE SCOPE
What's Included

A Coordinated Three-Part Envelope Upgrade

Weatherization is not one product. It is three core measures, delivered together, that transform a leaky building into a tight, efficient, and comfortable one. Every weatherization project we complete includes all three.

BPI Certified Building Performance Institute
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Thermal Performance

Insulation

Cellulose, Spray Foam, Fiberglass

Material selection based on building age, cavity access, and target R-value. We dense-pack walls without tear-out, blow attics to code-plus, and use closed-cell foam where moisture and air barriers are needed.

Where It Goes

Attic floors, exterior walls, rim joists, basements

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Pressure Control

Air Sealing

Diagnostic-Led, Blower Door Verified

Every leak point identified and sealed. Rim joists, top plates, penetrations, attic bypasses. We measure CFM50 before and after to document the improvement for utility rebate submission.

Where We Seal

Rim joists, top plates, penetrations, chases

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Delivery System

Duct Sealing

Mastic Sealed, Pressure Tested

Leaky ducts in unconditioned spaces can lose up to 30% of conditioned air. We seal joints with mastic and verify with duct pressure testing. Often the single highest-impact measure in older buildings.

What We Address

Supply, return, plenums, boots, joints

Income-Eligible Buildings
100%

Weatherization at Zero Out-of-Pocket

Building Energy Experts is an authorized contractor for the Nicor Gas weatherization program, a small group of vetted contractors in Illinois delivering fully-funded envelope upgrades to qualifying multifamily buildings. The most comprehensive rebate program available in our region.

Building Type 3+ unit multifamily in the Nicor Gas service territory
Income Eligibility Based on tenant median income, not owner income
Coverage Insulation, air sealing, and duct sealing fully covered