# How a $5,000 Rooftop AC Install Is Damaging the Roof

- Link: https://propertyinspectionsplus.com/rooftop-hvac-unit-roof-damage/
- Published: 2026-10-24T09:24:50+00:00
- Author: homeinspectordan

On this inspection, a poorly installed $5,000 rooftop HVAC unit is on track to cause
tens of thousands of dollars in roof damage. It’s a good example of how one shortcut
on the roof spreads into the attic, the ducts and the rest of the house.

## On the roof

The unit is sitting on soft, damaged sheathing that has been exposed to moisture
for too long. The weight and vibration of the HVAC have made the roof surface uneven
and unstable. That’s not safe to walk on, and it’s not going to hold up.

## In the attic

 * The sheathing under the unit is rotting and warped, which confirmed what I saw
   from above.
 * The ductwork is poorly routed, patched together with mismatched materials and
   holding moisture.
 * Exposed wiring and outdoor outlets that weren’t installed correctly.

## Plumbing and remodel shortcuts

 * Clogged hot water lines. Parts of the house don’t get hot water at all.
 * Flex drain traps under the sinks.
 * Vanity drawers cut up to fit around plumbing.
 * Sloppy shower tile work.

## Rooftop units in Arizona

Rooftop package units are common on older Phoenix-area homes. They work fine when
they sit on a proper curb or stand and the roof around them is sealed and maintained.
When a unit is set straight onto a tired roof, every rain and every AC cycle makes
it worse. If the house you’re buying has a rooftop unit, have your inspector check
the roof under it and the attic directly below it.

Buying a flipped house? Don’t skip the inspection. These hidden issues add up fast.
Here’s what’s included in a [residential home inspection](https://propertyinspectionsplus.com/residential-home-inspection/).

## Watch the inspection

See the roof and attic in the video above, or [watch it on YouTube](https://www.youtube.com/watch?v=f0Z6FlmixeQ).
[Book your inspection online](https://app.spectora.com/home-inspectors/my-inspection-company-f8d6dbae4e/schedule)
or call [623-399-0079](https://propertyinspectionsplus.com/rooftop-hvac-unit-roof-damage/6233990079).

Property Inspections Plus is a [Gilbert, AZ home inspection](https://propertyinspectionsplus.com/)
company led by Certified Master Inspector Dan Pierce. We inspect homes across the
East Valley, the Phoenix metro and the rest of Arizona. See all of our [service areas](https://propertyinspectionsplus.com/service-areas/).