How to Tell if Your Home is Under-Insulated (For Homeowners, Renters, and Building Owners)


Are you finding that your home can be uncomfortably hot in summer or chilly in the winter? Or maybe you’re noticing unusually high energy bills? These could be signs that your home lacks proper insulation and that your home might be under-insulated, or even have no insulation at all! Whether you’re a homeowner or a renter, understanding the signs of poor or non-existent insulation is crucial for maintaining comfort and energy efficiency in your space.

In this short guide, we’ll walk through various indicators that suggest your home may be under-insulated or even completely lacking insulation. By recognizing these tell-tale signs, you can take steps to address insulation issues and make your home more comfortable and energy efficient.

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Energy Bills and Increased Air Conditioning and/or Heating Costs

If your energy bills seem higher than expected, it could be a sign that your home is under-insulated. An under-insulated home struggles to maintain a consistent temperature, leading to increased heating or cooling costs.

For example, if you’re experiencing higher than expected energy bills during the summer months, it may be due to your air conditioning system working harder to compensate for heat infiltration caused by inadequate insulation. To help offset any taxes, fees, etc. that are taking money out of your pocket, consider adding more insulation to your home.

Temperature Fluctuations and Heat Transfer

Do you notice significant temperature differences between rooms or floors in your home? Inconsistent temperatures can indicate poor insulation, as heat escapes more readily from under-insulated areas. Touch the walls and floors of your home, especially those along exterior walls or over unheated spaces like crawl spaces. If they feel cold to the touch, it suggests that heat is escaping through inadequate insulation.

Drafts, High Indoor Temperatures, Or Uneven Cooling

Drafts are a major tell for air leakage. Feel for drafts around windows, doors, and outlets. Cold spots near these areas can suggest insufficient insulation.

If your home consistently feels uncomfortably warm, even when the outdoor temperatures are moderate, it could indicate that heat is entering (or leaking in the winter) into your home’s envelope due to insufficient insulation. Inadequate insulation can also result in uneven cooling throughout your home, with certain areas remaining warmer than others despite your air conditioning system running. This can be particularly noticeable in rooms located on upper floors or areas with direct sun exposure.

Ice Dams

Ice dams are formations of ice along the edges of your roof. They can occur when warm air escapes from your home’s interior, melting snow on the roof, which then refreezes at the colder edges. This could lead to water damage, leaks, and potential structural issues if left unresolved. Proper insulation helps prevent this heat loss and can help prevent ice dams from forming. Ice dams can also occur due to air leakage, not just insulation issues. Inadequate insulation may lead to heat conducting from inside to the attic space, warming the attic and causing snow to melt. Addressing air leakage is crucial to prevent ice dams, along with ensuring proper insulation levels.

Conduct a Visual Inspection

Do a quick visual check of your attic, walls, and crawl spaces for insulation. If you can see the ceiling joists in your attic, it may need more insulation. Similarly, if you notice thin or uneven insulation in your walls, it may be inadequate. This also goes for inappropriate insulating materials such as bubble wrap, straw, sawdust, etc.

Visible Gaps and Cracks

Inspect the exterior of your home for visible gaps, cracks, or openings around windows, doors, cellars, and foundation areas. These gaps allow air to infiltrate or escape, reducing the effectiveness of your insulation and increasing energy consumption.

Discolouration and Staining or Visible Mould Growth

Check for visible signs of mould growth on walls, ceilings, baseboards, and other surfaces, especially in areas prone to moisture build-up or poor insulation. Mould may appear as black or greenish patches and often has a musty odour.

Similarly, water stains, discolouration, or peeling paint on walls and ceilings can indicate past or ongoing moisture problems, which may be exacerbated by inadequate insulation. This is because the wall gets cold enough to reach the dew point (due to inadequate insulation or thermal bridges). Addressing both insulation and moisture issues is crucial to prevent further mould growth and structural damage.

Musty Odours

Persistent musty or damp odours in certain areas of your home, such as basements, crawl spaces, or attics, may indicate mould growth hidden behind walls or in concealed spaces. Inadequate insulation can exacerbate moisture retention and contribute to these odours.

Noise Levels

Pay attention to the levels of noise you hear inside your home. If you can easily hear conversations, footsteps, or other sounds from adjacent rooms or outside, it may indicate insufficient acoustic insulation. If your walls and ceilings are thin or lack sufficient mass, they may not effectively block out external noise. Adding additional insulation or soundproofing materials can help improve acoustic performance.

Age of the Insulation or the Home

If your home is older and hasn’t been updated, it may have insufficient insulation. Building codes and insulation standards have evolved over time, so older homes often lack the insulation levels found in newer construction.

Consult a Professional

If you’re unsure about the insulation levels in your home or how to assess them, consider hiring a local professional energy auditor or insulation contractor. They can conduct a thorough assessment and recommend appropriate insulation measures.