Last updated: October 14, 2026
By using Loft Insulation Calc at loftinsulationcalc.com ("the site", "we", "us"), you agree to these terms. If you don't agree, please don't use the site.
Estimates are for planning only
The calculators give planning estimates of insulation targets, depths, quantities and material costs. They're meant to help you prepare for a project and to compare options. They aren't:
- professional, engineering, architectural or legal advice;
- a substitute for an inspection, an energy audit or a qualified contractor's assessment; or
- a guarantee of how much material a job will take, what it will cost, or how your home will perform.
Results depend on the information you enter and on assumptions explained in our methodology. Real homes differ: framing, obstructions, uneven surfaces, product changes and installation quality all affect the outcome.
Check before you buy or build
Before you start, check:
- the product label and coverage chart on the insulation you actually buy, because coverage varies between brands and products;
- your local building code, since states and cities adopt and amend energy codes differently, and some projects need a permit and inspection; and
- current prices at your store, because the prices on this site are typical figures from a given date and will change.
Where the site and a product's label, the manufacturer's instructions or your local code disagree, follow the label, the instructions and the code.
Safety
Insulation work can be hazardous. You're responsible for working safely and for deciding when to hire a professional. In particular:
- Attics get very hot. Work at a cool time of day, take breaks and drink water.
- Walk only on joists or boards laid across them. Ceiling drywall won't hold your weight.
- Electrical wiring can be damaged or dangerous. Don't disturb it, keep insulation away from non-IC-rated recessed lights, and have an electrician check old knob-and-tube wiring.
- Chimneys, flues and vents need clearance from insulation, as set by the product instructions and local code.
- Vermiculite insulation may contain asbestos. Don't disturb it; the EPA advises having it handled by a trained, accredited asbestos professional.
- Protective gear: wear an N95 mask, goggles, gloves and long sleeves when handling insulation.
- Spray foam should be installed by trained professionals.
No warranty
The site and its content are provided "as is" and "as available". To the fullest extent the law allows, we make no warranties of any kind, express or implied, including warranties of accuracy, completeness, fitness for a particular purpose or non-infringement. We work to keep the data accurate and sourced, but we can't promise it's free of errors or up to date.
Limitation of liability
To the fullest extent the law allows, we aren't liable for any loss or damage arising from your use of the site or reliance on its estimates. This includes the cost of materials, labor, damage to property, personal injury, or indirect or consequential losses. Some places don't allow certain warranties or liabilities to be excluded, so some of these limits may not apply to you. Nothing in these terms limits liability that can't be limited by law.
Links to other sites
The site links to third-party sites such as ENERGY STAR, government agencies, manufacturers and retailers, mainly as sources. We don't control those sites and aren't responsible for their content, products, prices or privacy practices. A link doesn't mean we endorse the site or what it sells. If the site ever carries affiliate links, our affiliate disclosure explains how they work.
Using the site
You're welcome to use the calculators and share links to results. Please don't copy the site's content or data in bulk for republication, interfere with how the site works, or use it for anything unlawful.
Privacy
How we handle information is covered by our privacy policy. In short: no accounts, no cookies, and calculations run in your browser.
Changes
We may update these terms from time to time. The date at the top shows when they last changed. Continuing to use the site after a change means you accept the updated terms.
Contact
Questions about these terms: info@loftinsulationcalc.com