Drafts sneaking in around your windows? Rooms that feel cold even when the heat is on? In Whatcom County’s cool, wet seasons, small leaks and thin insulation can add up to higher bills and lower comfort. You can fix that. In this guide, you’ll learn what to look for, which upgrades matter most for older homes, and where to find local incentives. Let’s dive in.

Why weatherproofing matters in Whatcom County

Whatcom County gets cool, wet winters and mild summers. Heating needs are higher than cooling needs, so insulation and moisture control pay off fast. According to local climate data for Bellingham, precipitation is concentrated in fall through spring, which makes attic and wall insulation plus moisture management top priorities (Bellingham climate normals).

Washington’s energy code sets prescriptive minimums that are useful targets for upgrades in older homes. For our region, the state lists R-60 for attics, R-30 for floors, and wood-frame walls at R-20 plus R-5 continuous or R-13 plus R-10 continuous (Washington State Energy Code).

Start smart: inspect and test

Begin with a simple walk-through. Feel for drafts near windows and doors. Peek in the attic to check insulation depth and look for daylight around penetrations. Note any rooms above crawlspaces that feel cold.

For a deeper look, consider a professional energy audit with blower-door testing and infrared scanning. Diagnostics help you find the biggest leaks and moisture risks before you spend money on fixes (attic preparation and diagnostics overview).

Seal first, then insulate

Air sealing makes insulation work better. It also tackles the drafts you feel day to day.

Air sealing priorities

• Attic penetrations: top plates, plumbing and electrical chases, recessed lights, and the attic hatch. Seal gaps with caulk or low-expansion foam and add a gasketed, insulated hatch cover.
• Rim joists and sill plates: seal joints where the house meets the foundation. This is a common leak point.
• Windows and doors: add weatherstripping, door sweeps, and perimeter caulk.

Sealing these areas and adding insulation together can reduce heating and cooling costs by roughly 10 to 20 percent in many homes (ENERGY STAR savings guidance).

Attic insulation targets

If your attic is thin on insulation, it’s usually the best first upgrade. Aim to meet or approach R-60 for the attic when feasible per the state’s prescriptive path (state energy code targets). Focus on details: air seal first, add baffles to keep soffit vents clear, and insulate the attic access.

Walls, floors, and crawlspaces

Existing wall options

For finished walls, dense-packed cellulose or blown-in fiberglass can be installed through small holes with minimal disruption. Full wall rebuilds or exterior continuous insulation are usually best timed with larger remodels or re-siding. Because wall work costs more per square foot, most homeowners address attics and crawlspaces first.

Rim joists and floors over crawlspace

Rim joists are often cold and leaky. Insulate and air seal them with closed-cell spray foam or rigid foam plus sealant. For floors over crawlspaces, R-30 is a common target. In our damp climate, many homes benefit from sealed crawlspaces with a ground vapor barrier and correct venting strategy (ENERGY STAR crawlspace guidance).

Windows and quick draft fixes

Before replacing windows, try low-cost steps. Add weatherstripping and door sweeps, caulk exterior gaps, and consider storm windows or interior window panels. If you plan to upgrade glazing, check utility rebates for qualifying windows and air sealing measures (Cascade Natural Gas weatherization incentives).

Ducts, ventilation, and safety

Leaky ducts in unconditioned attics or crawlspaces can waste a lot of heat. Seal and insulate them where accessible. Make sure bathrooms and kitchens exhaust to the outside, and manage indoor humidity to prevent condensation.

If you tighten the house, always confirm combustion safety and ventilation afterward. Controlled ventilation protects indoor air quality and helps you avoid backdrafting on combustion appliances (safety and cold-weather prep overview).

Incentives and local help

• Opportunity Council: Qualifying households in Whatcom County can receive no-cost weatherization services that may include insulation, air sealing, and heating system safety checks. If you qualify, this is often the most direct path to getting work done affordably (Opportunity Council programs).
• Cascade Natural Gas: Rebates for attic, wall, and floor insulation and for prescriptive air sealing are available when program conditions are met. Many trade-ally contractors can apply rebates on your behalf (CNGC incentives).
• Other utilities and federal credits: Check your electricity provider for additional rebates, and review current federal tax credits for eligible insulation and air sealing work when planning your budget.

Permits, code, and health considerations

Routine attic insulation and basic air sealing usually do not require a permit, but mechanical, electrical, or structural changes may. Always check with the City of Bellingham or Whatcom County building department before major work. When you upgrade, use the Washington State Energy Code values as your performance target.

If your home was built before 1978, assume lead-based paint may be present and use lead-safe practices when disturbing painted surfaces. Vermiculite attic insulation and some older materials can contain asbestos, which requires testing and proper abatement by certified professionals (lead and asbestos overview).

What to do this week

• Check your attic insulation depth and look for visible gaps at the attic hatch, light fixtures, and plumbing penetrations.
• Seal easy leaks around doors and windows with weatherstripping and caulk.
• If you have a crawlspace, confirm you have a ground vapor barrier and look for signs of moisture.
• Get two to three bids for attic air sealing and insulation upgrades that target R-60.
• Explore local rebates and programs before you hire a contractor.

Ready to make your older Whatcom County home warmer, quieter, and more efficient? If you’re planning to buy an older home or prep yours for market, let’s map out the smartest upgrades for comfort and resale. Reach out to Whatcom County Homes to start the conversation.

FAQs

What R-values should I target in Whatcom County?

• Aim for roughly R-60 in the attic, R-30 for floors, and wall assemblies that meet R-20 plus R-5 continuous or R-13 plus R-10 continuous per the Washington State Energy Code.

What fixes usually deliver the fastest comfort gains in older homes?

• Air sealing plus adding attic insulation typically gives the biggest improvement per dollar and can cut heating and cooling costs by about 10 to 20 percent in many homes (ENERGY STAR savings guidance).

How should I handle crawlspace moisture in the Pacific Northwest?

• Use a ground vapor barrier, air seal and insulate rim joists, and consider a sealed or conditioned crawlspace approach if moisture is persistent (ENERGY STAR crawlspace guidance).

Are there local rebates for insulation and air sealing?

• Yes. Cascade Natural Gas offers weatherization incentives, and Opportunity Council provides no-cost services for qualifying households in Whatcom County.

Do I need to worry about lead paint or asbestos when insulating?

• In pre-1978 homes, use lead-safe practices, and test suspect materials like vermiculite for asbestos before disturbing them; use certified professionals if hazards are present (lead and asbestos overview).