Allstate: Improve Insulation

Make your home’s envelope work for comfort, costs, and future buyers  

Winter’s not over yet, but most homeowners in cold climates learned an invaluable lesson this year. How well their house was insulated makes a huge difference in comfort. If you found yours cold, make improvements before next winter—and definitely before summer’s hot days. Good insulation helps cool your house as temperatures rise.

But it does more. Your heating and cooling costs will drop, and you’ll entice buyers, who increasingly compare these expenses when they house hunt. Here’s how to proceed:

Think found money. More municipalities, cities, states, the federal government, and even utility companies offer incentives and tax rebates when you purchase high-efficiency products and materials, says Daniel DiClerico, co-author with Marianne Cusato of The Just Right Home. Check the U.S. Department of Energy’s database for efficiency related savings. 

Get an energy audit. If you own an older home, get its energy efficiency assessed to know where leaks occur and insulation needs improvement. Think of it as a physical exam for your house. A blower door test, for instance, simulates a 20-mile wind and detects air leaks. An audit provides your home’s R-value, which measures how well insulation resists heat—and cold—traveling through it. Newer homes require a comparable HERS, or Home Energy Rating System, measurement.   

Who should perform it. Many contractors can do an audit, but be sure to work with someone licensed, bonded, and insured, and get references. The quality of workmanship matters almost as much as materials installed. Two national organizations that train and certify professionals for this work represent a good starting point: RESNET, Residential Energy Services Network, and BPI, The Building Performance Institute. Also ask your electric or gas company because many perform audits. Most audits cost between $300 and $400, but some states and municipalities provide them for free, as well as software to project savings. 

Pick the best insulation. Contractors use different materials, methods, and amounts, depending on your area. Check the federal government’s map for recommendations: 

  • Blown-in fiberglass, made of different products, including from recycled plastic bottles, functions well, and has been around for decades.
  • Blown-in cellulose, made from shredded newspaper, comes in loose filled so it’s powdery like fresh snow and densely packed, which has a higher R-value, prevents more air flow, but is among the most expensive. Cellulose’s properties deter pests and retard fire.  
  • Spray foam, a mix of chemicals, becomes rigid after it cures, is moisture resistant, and acts as an excellent air sealant. It also can thwart pests. But, it can’t be applied over existing insulation.

Install in the right places. Focus on where insulation needs beefing up or is missing, but most contractors suggest working from the top down, if your budget is tight:

  • Attic. If you have an attic, install it on top of the floor or under the roof deck, based on your home’s configuration and where HVAC equipment is located. 
  • Walls. In cold climates, add insulation in interior or exterior walls by drilling 3” holes, blowing in cellulose, and covering openings.
  • Basements. Install it near joists or where wood meets concrete to seal gaps, as well as around the perimeter. 
  • Additions. Too often the area where a room is added is neglected; fill this gap. 

Don’t forget “low-hanging fruit.” Many do-it-yourself improvements can increase insulation--caulking and weather stripping around windows, doors, and thresholds; plugging light holes and plumbing gaps; installing storm windows; adding a programmable thermostat to lower temperatures automatically. Plant, too, says BP certified contractor Scott Fischer of Ciel Power: Shrubs and foundation materials reduce cold winter air; leafy trees on a south-facing lawn cut summer heat. Hire a professional, however, to wrap and tape ductwork, which is more complicated and messy.