The best attic insulation for old houses is blown-in cellulose paired with thorough air sealing. Cellulose is affordable, fills irregular gaps perfectly, and avoids disturbing historic framing. For a premium, high-performance upgrade, closed-cell spray foam or rigid mineral wool provides an excellent air seal, though proper moisture management is critical.
Insulating a 2,000 sq. ft. attic costs between $2,000 and $9,000, with most homeowners paying around $3,600 to $5,800 for professional installation. The wide price range depends on the type of insulation, labor rates, and whether old insulation requires removal.
For most attics, blown insulation is better than rolled insulation. Blown-in is ideal for older homes or attics with irregular framing, as the machine-blown material conforms tightly around pipes, wires, and joists. Rolled insulation is better for brand-new, empty attics with no obstructions.
While both types provide insulation, R30 is the better option for maximizing energy savings in areas where heat loss or gain is a major concern. For example, R19 may suffice for interior walls, but R30 is more appropriate for exterior-facing attics or floors.
Fibre-based insulation, such as sheep's wool or hemp, works particularly well with old buildings. It has good thermal properties and, importantly, is 'breathable', although tends to cost more than mainstream products.
Closed cell spray foam is rigid once set. It is a better thermal insulator and was previously sold to stabilise failing roofs. But if it has been used inappropriately or installed poorly, it might put stress on timbers, restrict air circulation and put them at risk of decaying.
Insulating your loft will keep your house warmer but make the roof space above colder. Without their own insulation, pipes and tanks could freeze and an uninsulated loft hatch could let cold draughts into your house. However, don't insulate underneath your water tank, because this can cause your water to freeze.
Yes, it's possible to over-insulate your attic, and doing so can create more problems than benefits. Over insulating an attic can block proper airflow and trap moisture. As a result, it can lead to mold growth, wood rot, and compromised structural integrity.
When balancing upfront cost and overall thermal efficiency, the cheapest and most effective standard insulation is fiberglass batt insulation. However, if you are looking for long-term savings through superior air sealing, dense-pack cellulose often provides the best overall value.
Mice are curious and always searching for safe, snug, and warm nesting sites. Attics filled with blown-in insulation provide an excellent option–from the mice's point of view. As long as there is a ready food source. Mice are omnivorous and will eat and chew on almost anything including wood and electrical wires.
The safest and healthiest insulation for an attic is cellulose or mineral wool (rockwool). Both are naturally fire-resistant, free of harmful off-gassing chemicals like formaldehyde, and highly effective at blocking noise and resisting mold.
Because spray foam can trap moisture, hide the condition of the roof, make it difficult for surveyors to inspect, which means risks like timber decay, dry rot, and not forgetting increased fire risk. If you've got it or you're buying a property that does, this is something you need to know upfront.
Blown-in insulation is popular for filling irregular spaces, but it presents notable drawbacks like settling over time, poor moisture resistance, and messy maintenance. Proper attic ventilation is also required to prevent the material from shifting or clogging airways.
Fall is an ideal time for insulation.
Adding insulation before winter can help reduce heating bills significantly. Spring is another excellent option for installation. It provides an opportunity to prepare your home for summer's heat. Insulating in spring can keep your home cooler and reduce air conditioning costs.
Covers All Major Insulation Types – Whether you're adding insulation to your attic, walls, basement, or crawl space, you can qualify as long as the materials meet efficiency standards.
Attic insulation installation ranges from $1.50 sq/ft. to $2.45 sq/ft. The average cost of attic insulation installation is $1.80 sq/ft.
The Amish rely on natural, low-tech, and self-sufficient methods to manage mice. Because they generally avoid chemical poisons, they focus on three core pillars: prevention, natural deterrents, and mechanical traps.
Potential problems with spray foam insulation
reduce air circulation and ventilation within a roof space. lead to dampness and condensation on the underside of a roof because it forms an air barrier and stops moisture from escaping. place timber-framed roofs at risk of decay.
While traditional fiberglass and cellulose are soft and easy for mice to tunnel through, true "rodent-proof insulation" relies on dense, unpalatable materials like mineral wool, combined with solid physical barriers to block entry points.
What time of year is Insulation cheapest?
The Environmental Protection Agency banned spray-on asbestos insulation in 1973, certain types of pipe and block insulation in 1975 and new asbestos insulation products in 1989. In 2024, the EPA banned most uses of chrysotile asbestos products, including imports.
Adding insulation to the attic is generally a moderately difficult do-it-yourself (DIY) project, but the benefits can be substantial. If you are doing a major home renovation project, now may be a great time to tackle this project too.
Unfaced insulation is great for new construction, remodels, walls, floors, ceilings, basements, attics and crawlspaces. It's best used for interior wall applications that do not face the outside and also in rooms that don't need moisture control, like living rooms, dining rooms and studies.
The 7 and 7 rule for attic conversions refers to the common requirement that finished attics be at least 7 feet wide and 70 square feet, with 7-foot ceilings over at least half. Keep in mind that this is a general guideline. Local building codes may have stricter requirements that supersede this rule.
Yes, your lungs can get rid of fiberglass, but how effectively they do it depends on the size of the fibers and where they end up in your respiratory tract.