Skip to main content

Free second opinion

Maintenance

Energy Audits & Home Performance in Charleston, SC

An energy audit finds where your home actually loses conditioned air — duct leakage, thin insulation, and air gaps — so you fix causes instead of paying the symptom on every bill. Holy City performs audits, blow-in and fiberglass insulation, and air sealing across the Lowcountry.

What this service covers

A home-performance visit measures how your house holds conditioned air: load calculations, insulation levels, duct condition, and the air-sealing gaps that let July in and your cooling out.

The fixes are unglamorous and effective — blow-in insulation, fiberglass insulation, and targeted air sealing, guided by what the assessment actually finds. Our team's training in energy and environmental performance, including LEED credentials noted on our energy pages, shapes how we evaluate the whole house rather than one appliance.

Why it matters in the Lowcountry

In a climate that runs air conditioning most of the year, envelope losses are a tax on every single cooling hour. A right-sized system in a leaky house still loses.

Humidity rides in through the same gaps as heat — sealing them helps the moisture battle every Lowcountry home fights.

Signs it’s time to call

  • Cooling bills that climb every year without a rate change
  • Rooms that never match the thermostat
  • A system that runs constantly on hot afternoons
  • An attic you can feel radiating heat into the ceiling below

How the visit works

  1. Assess

    We evaluate insulation, ductwork, and air leakage, and run the load numbers for your home.

  2. Prioritize

    You get a ranked list — biggest comfort-per-dollar first — instead of a bundle of everything.

  3. Fix

    Insulation and air sealing, done cleanly, with results you can feel the same week.

What affects the price

Every home is different, so we quote in writing before work begins. The main factors:

  • Attic size and access
  • Existing insulation condition and removal needs
  • Target insulation level
  • Extent of air sealing required

Keeping it running

  • Recheck attic insulation after any roof or duct work.
  • Keep an eye on rooms that drift — new comfort gaps usually mean new air gaps.

Energy Audits & Home Performance: common questions


Is an energy audit worth it before replacing my system?

Often, yes. Fixing envelope losses first can let a smaller, less expensive system do the job — and whatever you install performs closer to its rating.

What insulation do you install?

We specialize in blow-in insulation and fiberglass insulation, paired with air sealing where the assessment shows leakage.

Will this help with humidity?

It helps meaningfully. Outdoor air carries moisture through every gap it finds; sealing the envelope reduces the load your AC and any dehumidification have to handle.

Rainbow Row's pastel historic houses on East Bay Street in Charleston, South Carolina

Y’all deserve to be comfortable.

Schedule an appointment with us today — or call and talk to a real person, until 9 PM.