Fiberglass Insulation in Washington, DC

Fiberglass remains the workhorse insulation for new construction and renovation work in Washington, DC. It is fast to install, easy to inspect, code-compliant at standard R-13 / R-21 / R-30 / R-49 thicknesses, and inexpensive enough that the budget on a Navy Yard townhome or a NoMa condo build-out usually pencils with fiberglass first. Our crews install fiberglass batts in walls and floors and blow loose-fill fiberglass into vented attics for clients who want a simple, code-compliant install at the lowest price.

Where Fiberglass Is the Right Call in DC

New construction townhomes (Navy Yard, NoMa, Capitol Riverfront): Standard fiberglass batts at R-13 in 2x4 walls and R-21 in 2x6 walls hit code at the lowest cost. Vented attics over conditioned space: Blown-in loose-fill fiberglass at R-49 is fast and inspector-friendly. Condo build-outs: Fiberglass batts in interior partitions where sound is not the primary concern. Renovation cavities: When you have open framing and dry, accessible bays, fiberglass goes in faster than any other material. For wet or below-grade applications, or anywhere air-sealing is the priority, we steer clients to spray foam or dense-pack cellulose instead — fiberglass does not air-seal, and a fiberglass-only install will leak.

Faced or Unfaced — Climate Zone 4 Vapor Strategy

DC sits in DOE Climate Zone 4-A (mixed humid). Code allows but does not require a Class II vapor retarder on the warm side of insulated assemblies. For most DC walls we install kraft-faced fiberglass with the kraft toward the interior, which gives you the vapor-retarder function without an extra membrane layer. For ceilings under vented attics we go unfaced. Mineral wool batts are an upgrade option when sound transmission, fire rating, or higher density is the priority — see our batt insulation page for those specs.

A Clean, Careful Install — Run From Our Falls Church Shop

DMV Foam is headquartered in Falls Church — about 25 minutes from any DC job site. Every project begins with a walkthrough and a clear scope that lists target R-values by area. We pull DCRA permits when required, protect floors and finishes, set rulers and depth markers for attic blow-in work, and place each batt with full contact so there are no voids or compressions. Around recessed lights, corners, and rim areas, our crew makes the precise cuts that keep coverage continuous. We work daily across Capitol Hill, Columbia Heights, Georgetown, Navy Yard, Adams Morgan, Dupont Circle, and NoMa.