What Causes Mold on Ceiling?

Find out quickly what caused the mold on your ceiling and what to do about it.

Mold on a ceiling is a good indicator that there are water leaks, which typically come from three sources: the roof, HVAC systems, or plumbing.

Another cause can be poor ventilation and an overall high humidity, but these usually don’t cause bigger mold problems.

If you see a lot of mold and are wondering whether you have a leak or not, keep reading. We’ll now go over the possible types of leaks that led to ceiling mold.

Roof Leaks

Roof leaks usually occur when it rains heavily. It is a telltale sign that your roof has damaged shingles that need repair.

Over time, roofs wear down due to exposure to harsh weather conditions.

When rainwater penetrates these gaps, it finds its way into your home and eventually creates that wet spot on the ceiling.

How to Know?

Roof leaks generally occur near roof penetrations or features. Look for moldy spots that connect to:

Spaces beneath vents, chimneys, or skylights
Spots that follow the roof dips or slopes

Quick Test: If you suspect a roof leak:

Check your attic (if accessible) during the daytime.
Look for water stains and mold on the bottom of the roof deck above the ceiling area.
Look for damp insulation in that area.

HVAC Leak

If you spot mold on the ceiling around air ducts or vents, then this is likely why.

When an AC starts to malfunction or is clogged, it drips water. Then the walls eventually absorb that water, which leads to mold growth.

How to Know?

The mold is usually:

Near or right beneath AC equipment/ductwork.
Near your air handler or where refrigerant lines flow.
In rooms underneath HVAC units in attics.

The leaks occur when AC is operating. It may be worse on really humid days.

If there is a problem with the condensate drain, this can occur all year.

A few other signs:

It may be a steady drip.
It’s accompanied by increased humidity in the room.
Sometimes noticeable condensation on surrounding vents

Pipe Leak

Corroded pipes, loose fittings, or increased water pressure contribute to pipe leaks.

How to Know?

In terms of location:

Usually found right on the first floor, directly beneath your bathrooms, kitchens, or laundry areas.
Frequently follows the path of known plumbing lines.
Can happen on any floor.

This type of leak happens regardless of weather conditions, and it may intensify during or shortly after water usage upstairs.

A few additional signs:

There is a consistent point source.
Dripping sounds in the walls.
Feels warm if it’s a hot water pipe.
Your water bill is higher than usual.

What to Do About The Water Leak and Mold

Call Superior Contract Cleaning right away!

We will assess the damage and fix the problem.

You might be tempted to grab a ladder and try to fix it yourself, but some repairs require professional help.

This is because identifying and repairing the source of a leak typically requires specialized knowledge and tools, like moisture meters, for example.

Not to mention the health concerns from mold, which could include worsened allergies and asthma.

There is so much knowledge, skill, and experience required to tackle these types of projects, which is why it’s best to call in a professional.