Attic Insulation Contractors - Free Estimates

Blow-in fiberglass and cellulose are top choices

Most homes require additional attic insulation. The minimal levels of attic insulation required by local building codes aren't considered adequate today because of rising energy costs and increasing concern about the environmental damage caused by fossil fuel consumption.

Dr. Energy Saver offers Free Attic Insulation Estimates and Inspections. Our trained and authorized Dr. Energy Saver doctors and technicians can help you identify how much and what type of insulation is best for your attic.

Blowing in a blanket. Blow-in fiberglass insulation is installed with a long, flexible hose connected to a machine that shreds and blows the material.

The best types of attic insulation. In many older houses, the attic is insulated with fiberglass batts that are placed between ceiling joists. If the attic in your house is insulated with fiberglass batts, there's a good chance that this insulation can stay in place beneath a deeper layer of new insulation.

When new attic insulation is installed, it's usually blown into the attic. The advantage of blown (or blow-in) insulation isn't greater R-value; it's the fact that blow-in insulation can be installed faster, more uniformly and with less traffic through the house. Unlike in wall or floor applications, the attic provides enough room for a thick layer of insulation, so the "fluffy" nature of blown insulation isn't a disadvantage.

Blown fiberglass insulation (aka "loose-fill" fiberglass insulation) has an R-value of about 3.4 per in. It comes in dense blocks that are wrapped in plastic. To install the material, each block is cut in half and pushed into a combination shredder/blower machine that feeds a long, flexible installation hose.

Cellulose insulation is made from old newspapers that are shredded and then treated to resist combustion and mold. Since it's made from a waste material, cellulose is considered one of the greenest insulations available. To insulate walls in new construction "wet-spray" cellulose insulation can be blown between studs. A water-based binder and adhesive keeps this type of cellulose insulation in place as the insulation dries out. The cellulose insulation blown into attics is a dry mix of shredded newspaper rated at R-3.8 per in. It's installed with a blower machine similar to that used to install blown fiberglass insulation.

Insulation plus ventilation. Stapled to the roof sheathing between rafters, a pink plastic baffle prevents attic insulation from blocking ventilation from the soffit vents installed along the eaves.

Baffles and barriers keep attic insulation in place

You can't add more attic insulation without making some provisions to contain it. Otherwise, you might not be able to enter the attic without having insulation spill down into the living space. Another problem can occur when attic insulation extends into the eaves, covering soffit vents and preventing them from working properly. Also, if the attic has HVAC equipment such as an air handler, covering this equipment with insulation will limit accessibility for servicing.

Insulation baffles or barriers (aka dams) take care of these problems. (These are different than radiant barriers.) Some readymade baffles are designed for installation between rafters to keep ventilation channels open. In other situations, an energy technician will fabricate barriers from different sheet materials like plywood or rigid insulation board.

Spray foam seals a plumbing penetration. Holes made in walls for plumbing, vents and electrical wires all provide air leakage pathways. Energy technicians typically seal these leaks with spray foam.

Attic air sealing: a must-do upgrade before adding insulation

It's a common misconception that adding more attic insulation stops air leaks. The truth is that insulation filters air; it doesn't block it. For proof, you don't need to look any farther than the air filter on your furnace or air handler. It's made of fiberglass, just like fiberglass insulation. To properly air-seal your attic, energy technicians need to move aside existing attic insulation and expose all the wall framing, can lights, soffits, vent fans and other details; then they seal all the holes, gaps and cracks they can find. They'll also seal around the attic stair or hatch and around chimneys and chases for ducts, plumbing and wiring.

When a blower door test is performed after upgrading the attic air barrier, there will usually be a dramatic reduction in air leakage. Only then is it appropriate to proceed with adding attic insulation.

For a good overview of what to do - and what not to do - with attic insulation, check out Episode 2 of Tom & Larry's Excellent Home Energy Saving Show below:

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