Insulation Guides

34 guides on doing insulation work properly — installation walkthroughs, material comparisons, 2026 pricing and the gear worth buying. No fluff, no signup.

How-to

Step-by-step installation walkthroughs for every part of the house.

How to Insulate an AtticA step-by-step attic insulation guide: air sealing first, baffles, choosing batts vs blown-in, hitting R-49 to R-60, and the mistakes that waste the whole job.9 min read How to Install Batt InsulationCutting, friction-fitting, splitting around wiring and stapling batts so they actually hit their rated R-value. Includes the compression rules most DIY jobs break.8 min read How to Blow In Attic InsulationRenting the blower, calculating bags, hose handling, depth markers and two-person technique for DIY blown-in cellulose or fiberglass.8 min read How to Air Seal Before You InsulateWhere the leaks actually are, which sealant to use where, and why air sealing beats adding inches of insulation on top of a leaky ceiling.7 min read How to Find Air Leaks in Your HomeSmoke tests, infrared thermometers, thermal cameras, the hand test and blower doors — how to locate the drafts worth sealing.6 min read How to Insulate a Crawl SpaceWhether to insulate the floor above or the walls below, how to encapsulate with a vapor barrier, and what not to do in a damp crawl space.8 min read How to Insulate a BasementThe correct basement wall assembly: rigid foam against concrete, framing inside it, no fiberglass on bare block, plus rim joists and floors.8 min read How to Insulate a GarageWhat to insulate first in an attached or detached garage, door kits, ceiling R-values, and whether to heat the space at all.7 min read How to Remove Old Attic InsulationWhen removal is actually necessary, vacuum rental vs bagging by hand, safety gear, disposal, and what it costs to hire out.7 min read How to Insulate Rim JoistsCut-and-cobble rigid foam vs closed-cell spray foam in the rim joist, why fiberglass fails there, and how much heat this small area loses.6 min read

Comparisons

Material vs material, head to head, with real numbers.

Fiberglass vs Cellulose InsulationR-value per inch, cost, air sealing, settling, moisture and fire performance compared — and which one to blow into your attic.7 min read Spray Foam vs FiberglassWhere spray foam earns its 3–5x price premium over fiberglass, where it doesn't, and how the payback math actually works.8 min read Open-Cell vs Closed-Cell Spray FoamDensity, R-value, vapor permeance, cost per board foot and the assemblies each type belongs in.6 min read Mineral Wool vs FiberglassRockwool-style mineral wool compared with fiberglass batts on R-value, fire rating, sound control, water resistance and price.6 min read Batt vs Blown-In InsulationCoverage quality, cost, DIY difficulty and storage impact compared for attic floors, walls and floors.6 min read Rigid Foam vs Spray FoamEPS, XPS and polyiso boards compared with sprayed polyurethane on price, R-value, air sealing and DIY friendliness.7 min read Radiant Barrier vs Attic InsulationWhat radiant barriers actually do, where they pay off, and why they are an addition to — never a replacement for — R-value.6 min read Vapor Barrier vs Vapor RetarderPerm ratings, Class I/II/III materials, which side they go on by climate zone, and the double-barrier mistake that rots walls.7 min read DIY vs Hiring an Insulation ContractorWhich insulation jobs save the most money as DIY, which are worth hiring out, and what to ask before signing a quote.7 min read

Costs & R-Value

What things cost in 2026 and how much R-value you actually need.

What R-Value Do I Need?Recommended attic, wall, floor, crawl space and basement R-values for every US climate zone, plus how to convert R-value to inches.7 min read How Much Insulation Do I Need?Turn square footage into the units you actually buy: bags of loose fill, packs of batts, sheets of foam board and board feet of spray foam.6 min read Insulation Cost Per Square Foot2026 installed and DIY material prices per square foot for fiberglass, cellulose, mineral wool, rigid foam, open-cell and closed-cell spray foam.7 min read Attic Insulation CostWhat attic insulation costs by attic size and R-value in 2026, what contractors include, and how much DIY actually saves.7 min read Spray Foam Insulation CostOpen-cell and closed-cell prices per board foot, typical job totals for attics, crawl spaces and whole houses, plus DIY kit math.7 min read Insulation Labor CostWhat insulation crews charge per hour and per square foot, how long each job takes, and how labor splits out of a typical bid.6 min read Insulation Rebates and Tax CreditsThe federal 25C credit, home energy rebate programs, utility incentives and how to stack them on an insulation project.6 min read

Buying Guides

Tools, kits and materials worth owning for insulation work.

Best Insulation Blowers of 2026Rental machines vs owning a blower, hose length, hopper size and what to look for before you blow an attic yourself.6 min read Best DIY Spray Foam Kits of 2026Two-part foam kits and canned foam compared: yields, temperature limits, open vs closed cell, and which size to buy for rim joists or a crawl space.7 min read Best Radiant Barriers of 2026Perforated vs solid foil, single vs double sided, emissivity ratings and how to install radiant barrier so it keeps working.6 min read Best Safety Gear for Insulation WorkRespirators, coveralls, gloves and eye protection for fiberglass, cellulose and spray foam — what rating you need for each material.5 min read Best Thermal Leak Detectors of 2026Spot thermometers, thermal leak detectors and phone-attachment IR cameras compared for finding missing insulation and drafts.5 min read Best Air Sealing Products of 2026Canned foam, weatherstripping, outlet gaskets, window film and tapes — the cheap products that cut drafts before you add insulation.6 min read Best Garage Door Insulation Kits of 2026Foam board vs reflective vs batt garage door kits, R-values, panel counts and installation tips including door spring adjustment.5 min read Best Pipe and Water Heater InsulationFoam pipe sleeves, wall thickness by pipe size, water heater blankets and the safety rules for gas units.5 min read

Insulation gear worth owning

The tools and materials that show up on almost every insulation job.

Owens Corning R-19 Unfaced Fiberglass Insulation 77.5 Sq.ft (15 in x 93 in) 1 Batt

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Loctite Tite Foam Gaps & Cracks Spray Foam Sealant, 12 fl oz Can, 1 Pack - Polyurethane Expanding Insulation

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Respirator Mask with Filters set - Reusable Respirator Mask for Chemicals, Painting, Spraying, Epoxy Resin, Dust, DIY etc

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BLACK+DECKER Thermal Leak Detector (TLD100)

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Attic insulation

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