Old houses have charm original trim, cozy nooks, history in every squeaky floorboard. What they usually don’t have is good insulation. You’ll notice that fast on your first energy bill. If your place was built before modern energy codes, insulation upgrades are one of the quickest ways to improve comfort, lower costs, and breathe cleaner air.

Step 1: Find Out What You Already Have

Start with the attic. Open the hatch, grab a flashlight, and check the coverage. If you can see joists, you’re under insulated. Take a pinch: fluffy fibers point to fiberglass, gray flakes mean cellulose, and rigid panels are foam boards.

Walls are harder, but there’s a simple trick. Turn off the power, pop off an outlet cover on an exterior wall, and look inside with a flashlight. You’ll spot batts, loose fill, or sometimes nothing at all. Do this in a couple of rooms, older additions often vary from the original structure.

In the basement or crawl space, look for batts under floors or foam on walls. If you find bare framing or damp, sagging insulation, that’s a red flag for both performance and indoor air quality.

Don’t want to poke around yourself? Our team can handle it safely with a whole-home evaluation.

Step 2: Match Materials to the Space

Different areas need different treatments.

• Attics: Blown-in cellulose or fiberglass gives even coverage over joists and corners. For conditioned attics, spray foam insulates and seals in one step.
• Knee walls & sloped ceilings: Seal floor cavities first, then use dense-pack cellulose or mineral wool batts. Add ventilation baffles to keep airflow under the roof.
• Exterior walls: Dense-pack cellulose or blown-in fiberglass through small drilled holes is common. Injection foam works in some wall types if moisture is under control.
• Basements & crawls: Rigid foam on foundation walls with sealed seams is durable and moisture resistant. In vented crawls, many homeowners convert to closed, conditioned crawl spaces with insulation and a vapor barrier.
• Rim joists: Closed-cell spray foam or rigid foam seals one of the leakiest parts of an old house.

For tailored options, see our attic insulation installation service or ask about full-home plans.

Step 3: R-Values and Priorities

Attics almost always deliver the best return. In many climates, R-38 to R-60 is the target range. If joists are visible, you’re probably below R-19 easy savings right there.

Above grade walls usually need R-13 to R-21 inside cavities. If you’re residing, you can add continuous exterior insulation for even better performance. Basements and crawl walls do well with R-10 to R-15 rigid foam.

If budget is tight, follow this order: air seal first, then attic, then basement or crawl, and finally walls. Each step strengthens the next.

Step 4: Know When It’s Time to Replace

You don’t need special equipment to spot trouble.

Rooms that swing between hot and cold, energy bills creeping higher, or drafts and musty odors after rain are all signs. Visible issues like damp batts, mold on sheathing, or ice dams on the roof also tell you insulation isn’t doing its job.

If pests or moisture are involved, don’t bury the problem under new material. Old insulation needs to be removed and the space sanitized. Our attic cleaning and sanitation service handles that before anything new goes in.

Step 5: DIY or Call a Pro?

For small attic top ups, DIY can work. Just be careful not to block ventilation, compress batts, or step through drywall. Always wear gloves, goggles, and a respirator.

But bring in a pro if you see knob and tube wiring, moisture damage, vermiculite (possible asbestos), or if the job involves spray foam, dense pack walls, or tight crawl spaces. Pros also know how to combine air sealing, ventilation, and insulation into one plan something a quick DIY project can’t cover.

Why Insulation Belongs at the Top of the Move-In List

Better insulation isn’t only about lowering bills (though you’ll notice the difference). It’s also about comfort fewer drafts, steady temperatures, and quieter rooms. It’s about health removing damp or contaminated insulation improves indoor air quality. And it’s about durability less condensation, fewer ice dams, and longer roof and HVAC life.

If you’ve just moved into an older home and don’t know where to start, start overhead. We’ll turn your attic from a dusty, leaky mystery into a clean, sealed, insulated space that makes the rest of your projects easier to tackle.

Schedule your home insulation evaluation with Y&S Home Builders today.

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