Home Weatherization Checklist:
Lower Bills and Improve Comfort

Weatherization is one of the best investments a homeowner can make — the Department of Energy estimates that properly weatherized homes reduce heating and cooling costs by 15–30%. Many of the most impactful improvements cost under $50 and take an afternoon. Others require professional work but have payback periods of 3–7 years.

This checklist organizes improvements by location and impact so you can work through them systematically.

🏠 Attic (Highest Impact)

Heat rises. Attic air sealing and insulation is consistently the highest-ROI weatherization investment in most homes.

• ☐ Air seal attic bypasses — gaps around ceiling light fixtures, plumbing and electrical penetrations, top plates of interior walls. Use canned spray foam or caulk. This alone can save $100–$300/year.
• ☐ Check insulation level — recommended minimum is R-38 to R-60 depending on climate zone. Visually inspect: if you can see the joists, you need more insulation.
• ☐ Check attic hatch — the hatch is often uninsulated and unsealed. Add weatherstripping around the frame and rigid foam or batt insulation to the hatch itself.
• ☐ Check recessed lights — older recessed lights (non-IC-rated) allow air leakage and must be sealed with fire-rated covers before insulating.
• ☐ Inspect attic vents — confirm soffit and ridge vents are clear (not blocked by insulation). Proper ventilation prevents moisture buildup and ice dams.

🪟 Windows and Doors

• ☐ Replace worn weatherstripping on all exterior doors — foam compression strip or V-strip. A door with gaps costs $100–$200/year in lost efficiency. Weatherstripping kits cost $10–$25.
• ☐ Install door sweeps on exterior doors — the gap under the door is a major air leak source. Automatic door sweeps ($25–$50) seal when the door closes and lift when it opens.
• ☐ Caulk around window frames — exterior caulking where window frame meets siding, and interior caulking where trim meets drywall. Use paintable silicone or latex caulk.
• ☐ Apply window film on single-pane windows — low-emissivity (Low-E) film can reduce heat loss through single-pane glass by 30–40%. Much cheaper than window replacement ($30–$50 per window vs. $600–$1,200).
• ☐ Check window locks and seals — windows that don't close fully or lock properly are obvious air leak sources. Repair or replace hardware as needed.
• ☐ Consider storm windows for historic homes where full replacement isn't desirable — they add an effective insulating air gap at a fraction of the cost of replacement windows.

🏚️ Basement and Crawl Space

• ☐ Insulate rim joists — the band of framing where the floor joists meet the foundation walls. Cutting and fitting rigid foam boards into each bay (2" XPS foam = R-10) and sealing with spray foam is one of the best DIY weatherization projects.
• ☐ Seal foundation cracks — use hydraulic cement for active water leaks; polyurethane caulk for dry cracks. Prevents both air infiltration and moisture intrusion.
• ☐ Insulate basement walls or crawl space — a conditioned basement with insulated walls is more energy-efficient than an uninsulated one. In crawl spaces, encapsulation (sealed vapor barrier + insulated walls) is the modern standard.
• ☐ Check for drafts around pipes and wires entering from the exterior — seal with spray foam or caulk.
• ☐ Verify crawl space vents — modern building science often recommends closing and sealing crawl space vents and treating the crawl space as conditioned space. Consult a building professional before making changes.

🌡️ HVAC System

• ☐ Seal duct leaks — the average home loses 20–30% of conditioned air through leaky ducts. Seal with mastic sealant (not duct tape — it fails over time) or UL181-rated foil tape at joints and connections.
• ☐ Insulate ducts in unconditioned spaces — ducts running through an attic or crawl space should be insulated to at least R-6.
• ☐ Replace furnace filter — a clogged filter reduces airflow and efficiency. Replace every 1–3 months depending on filter type and home conditions.
• ☐ Schedule HVAC tune-up — annual professional maintenance improves efficiency 5–15% and extends equipment life. Include duct inspection.
• ☐ Install a smart/programmable thermostat — setback thermostats that lower heat at night and while you're away can save 10–15% on heating and cooling. Most pay for themselves in under 2 years.

💧 Water Heating

• ☐ Insulate water heater tank — wrap older tanks with an insulating blanket ($25–$40) to reduce standby heat loss 25–45%. Most effective on tanks older than 5 years or located in unheated spaces.
• ☐ Insulate hot water pipes — foam pipe insulation ($1–$2/foot) on the first 6 feet of pipe from the water heater reduces heat loss. Also keeps water hotter at the tap.
• ☐ Lower water heater temperature — setting to 120°F (the EPA recommendation) instead of the factory default 140°F saves 6–10% on water heating costs and reduces scalding risk.
• ☐ Install low-flow showerheads and faucet aerators — reduces hot water use 25–60% with no perceived performance loss on modern low-flow fixtures.

💡 Quick Wins (Under $25 Each)

• ☐ Seal gaps around electrical outlets and switches on exterior walls — use foam gaskets made for this purpose ($5 for a pack)
• ☐ Add fireplace damper seal if the damper is worn or drafty (chimney balloons are temporary; damper replacement is permanent)
• ☐ Install door draft snakes on unused exterior doors
• ☐ Replace incandescent bulbs with LEDs — 75–80% less electricity for the same light, plus less waste heat in summer
• ☐ Add thermal curtains to large window areas — reduce heat loss through glass by 25% in winter

DIY vs. Professional: When to Call a Handyman

For more detail on specific projects, see our guides on weatherstripping doors and windows and home insulation types.