Moisture Stains on My Ceiling or Dark Stains around the HVAC Vents Covers

A lot of homes we inspect in Florida have condensation on the HVAC duct vent covers and moisture stains or mold on the ceiling around the vent.  The cold air from the vent coming in contact with warm air at the ceiling or uninsulated duct boots in the attic causes condensation to form on the vent covers.  Frequently, this condensation causes moisture stains on the ceiling.  The moisture stains can be an ongoing challenge if the cause of the condensation is not addressed. 

The water marks on the ceiling and the droplets of moisture on the vent cover are likely caused by insufficient insulation on the ducts in the attic, inadequate insulation or uninsulated vent boots, or leaking of hot / warm attic air around the vent boots. 

What is a vent boot?   

The vent boot is the box in the attic that the air conditioning duct connects to on one side and the vent cover on the ceiling is screwed into.  Newer boots are often constructed out of insulation board or duct board.  The older types of boots were constructed out of metal.

The above picture shows an uninsulated vent boot attached to the HVAC duct.  The vent cover connects to the vent boot on the inside of the ceiling.  This boot has no insulation and the joints are not sealed well.  The sealant between the boot and the ductwork is leaking and there is no sealant between the duct and the ceiling.  Moisture accumulating on the vent boot drips down until it is absorbed by the drywall ceiling board causing moisture stains around the vent cover.

People often mistake the dark stains that sometime form around the vent for mold.  The plausible cause of the dark stains is the vent boot was not sealed to the ceiling board.  The dust from the attic, then sticks to and stains the moist drywall board around the vent cover.

When you see the stains around your ceiling vent covers don’t ignore them.  Water damage is costly to repair and moist conditions may encourage mold growth.

Random Moisture Stains on your Ceiling

If you have random stains on the ceiling; it may be the joints are not sufficiently insulated or sealed.  Moisture stains are visible at the joints of the ductwork in the attic in the picture above.  Condensation forms on the joint and may not evaporate in the attic.  If the condensation continues to drip, it may saturate the insulation and cause moisture stains on your ceiling.

Recommendation:   We recommend sealing the joints to prevent cooling loss in the attic and random stains on the ceiling.  Sealing the joints will also improve the efficiency of your HVAC system and help reduce your cooling costs.

 

Main Causes of Condensation at AC Vents

Not enough insulation on the ducts themselves

Cold air traveling through your ductwork in a warm or hot attic forms condensation if the duct is uninsulated or under insulated. The air ducts in the attic should be well insulated.  You should have your air conditioning system and ducts inspected if it struggles to maintain a comfortable inside temperature on hot days or you notice condensation on the ceiling or vent cover.

The insulation on the duct above was separated from the duct.  Condensation had formed in the duct vapor barrier and over time had stained the middle of the ceiling.

Recommendation: Ducts in the attic should be well insulated and in good repair.  Damaged or old under insulated ducts should be replaced.  Consider replacing the ductwork in the attic if it is 20yrs or older.  It will be a good investment that will be easily recouped and will save you money on your future electric bills.

Uninsulated vent ‘boot’

The metal box in your attic that attaches to the duct and the vent cover screws to is the boot.  In an attic in Florida, the uninsulated boot will generate large amounts of condensation due to the cold air in the boot and the hot air in the attic.

Above is an uninsulated galvanized duct boot. This boot was cold in the hot attic and caused water to condense on it and drip onto the ceiling.

Recommendation:  We recommend having an HVAC contractor evaluate the condition of the ductwork.  Sealing the duct to vent boot joint and insulating old metal ducts will help reduce condensation around the vents.  Older deteriorated ductwork should be replaced.

Dark Stains around your vent Cover

Dark stains around your vent covers may be mold, but more likely it is dust collecting on the damp ceiling.  If the boot is not properly sealed to the ceiling, it will allow attic dust or dirt to seep out of the crack between the ceiling and the vent cover.  Also you may discover a leak where the vent boot attaches to the duct. If not properly sealed, the cold air leaks out, meets up with the warm attic air and creates condensation.

Recommendation:  Find and seal the leak. If the problem vent is easy to access from your attic, you may be able to check for and fix the problem yourself. We recommend consulting with a local HVAC contractor to evaluate and repair the HVAC ducts. 

Covering Stains around the Vent Cover

The dark or water stains around your vent cover are difficult to cover.  When the repairs have been made, the ducts have been caulked and no more condensation is present on the covers it will be time to cover the stains. 

Normal ceiling paint will not cover up these stains.  Moisture and dirt stains around the vent cover are stubborn stains.   Even with multiple coats of ceiling paint, the stains continue to bleed through the ceiling paint.

Recommendations:  We recommend you first cover the stains with two coats of KILZ 2 Multi Surface Primer & Stainblocker then paint with your choice of ceiling paint.

Frank Carr is the Owner / Inspector at First Choice Home Inspections in Deltona, FL serving Volusia, Seminole, Orange and Lake Counties. Formerly in the building trades, Frank’s focus is a safe home in the Orlando Metro and Daytona Beach areas of Central Florida and building FCHI. We believe that consumers have the right to expect the highest standards of thoroughness, fairness and effectiveness from their home inspector and that is exactly what we provide.
 

First Choice Home Inspections

Residential Home Inspections in Central Florida

(386) 624-3893 

Website:  http://1homeinspector.com

Facebook:  https://www.facebook.com/FirstChoiceHomeInspectionsLlc

LinkedIn:  https://www.linkedin.com/company/first-choice-home-inspections

Google+:  https://plus.google.com/+FirstChoiceHomeInspectionsDeltona

Twitter: https://twitter.com/1stChoiceHomeIn

Radiant Barriers Save Deltona Homeowners Money

What is a Radiant Barrier? Are they effective at reducing my energy bill?

We inspect a lot of hot dusty attics, some are 165° F. We see all kinds of situations where attic insulation is insufficient, ventilation is inadequate, and rarely find radiant barriers installed in attics. According to the Department of Energy Radiant Barriers work best in hot climates when used in conjunction with sufficient insulation and ventilation. Studies show that radiant barriers can reduce cooling costs 5% to 10%. The reduced heat gain may even allow for a smaller air conditioning system or improve effectiveness of an under rated systems.

Radiant barriers are installed in homes primarily to reduce summer heat gain and reduce cooling costs. Radiant barriers do not reduce heat conduction like thermal insulation materials. The barriers are comprised of a highly reflective substrate or foil that reflects radiant heat rather than absorbing it.

Heat Transfer

Like a cool spoon in cup of coffee conducts heat through its handle to your hand; heat travels from a warm area to a cool area by a combination of conduction, convection, and radiation. Heat flows by conduction from a hotter location within a material or assembly to a colder location. Heat transfer by convection occurs when a liquid or air, becomes lighter and rises. When liquid or air cools, it becomes heavier and falls. Radiant heat moves from hots surfaces and is absorbed by cooler materials or air. A car parked in the sun will absorb the radiant heat into the cars finish and transfer the heat thru the metal into the interior where it heats the air inside the car.

How Radiant Barriers Function

Most insulation materials work by slowing heat transfer. Radiant barriers and reflective insulation systems are designed to reduce the transfer radiant heat. Radiant barriers must have an air space to work. Radiant barrier are less effective when installed horizontally. Dust accumulation on the reflective surface reduces its reflective properties.

As the sun heats your roof, it makes your roof hot. The heat travels through the roofing materials to the attic side of your roof. It radiates the increased heat energy onto the cooler attic materials, the air conditioning ductwork and the ceiling of your home. A radiant barrier reduces the radiant heat transfer from the underside of the roof to the other surfaces in the attic.

Radiant Barriers help air conditioners cooling capacity

Radiant barriers are more effective in hot climates than in cool climates, especially when cooling air ducts are located in the attic. Some studies show that radiant barriers can reduce cooling costs 5% to 10% when used in a warm, sunny climate. The reduced heat gain may even allow for a smaller air conditioning system. In cool climates, however, it's usually more cost-effective to install more thermal insulation than to add a radiant barrier.

Frank Carr is the Owner / Inspector at First Choice Home Inspections in Deltona, FL serving Volusia, Seminole, Orange and Lake Counties. Formerly in the building trades, Frank’s focus is a safe home in the Orlando Metro and Daytona Beach areas of Central Florida and building FCHI. We believe that consumers have the right to expect the highest standards of thoroughness, fairness and effectiveness from their home inspector and that is exactly what we provide.
 

First Choice Home Inspections

Residential Home Inspections in Central Florida

(386) 624-3893 

Website:  http://1homeinspector.com

Facebook:  https://www.facebook.com/FirstChoiceHomeInspectionsLlc

LinkedIn:  https://www.linkedin.com/company/first-choice-home-inspections

Google+:  https://plus.google.com/+FirstChoiceHomeInspectionsDeltona

Twitter: https://twitter.com/1stChoiceHomeIn

What time is best for a home inspection?

Why is it not a good idea to schedule a summer home inspection in the afternoon?

There are many systems in the attic that require detailed investigation for a home inspection report.  The systems of the attic are trusses/rafters, sheathing, HVAC and exhaust duct work, electrical, insulation, ventilation, plumbing and in some cases HVAC components, chimneys and hot water heaters.

The plain and simple answer is the attic temperatures in Southern and even Northern states can reach extreme temperatures of 140 to 165 degrees Fahrenheit or even higher.  If you are paying for a home inspection and schedule your inspection for the afternoon; you will, most likely, not be getting a thorough inspection.  According to most state standards of practice(SOP) a home inspector does not have to enter the attic if the temperature in their opinion is extreme and dangerous to the inspector.

ASHI SOP
F.  Inspectors are NOT required to:

1.  Perform any procedure or operation that will, in the opinion of the inspector, likely be
dangerous to the inspector or other persons or damage the property or its systems or
components.

NAHI SOP

1.13 The inspector shall report on any system and component included in these standards of practice which were present at the time of the home inspection but were not inspected and provide the reason they were not inspected.

2.10 The inspector is not required to enter any premises that visibly shows a physical threat to the safety of the home inspector or others nor inspect any area or component that poses a danger to the inspector or others.

InterNachi SOP
III. The inspector is not required to:
C.  enter or access any area that may, in the opinion of the inspector, be unsafe.
F.  do anything which may, in the inspector's opinion, be unsafe or dangerous to the inspector or others, or damage property, such as, but not limited to:  walking on roof surfaces, climbing ladders, entering attic spaces, or negotiating with pets.
IV. The inspector is not required to:
A.  enter the attic or any unfinished spaces that are not readily accessible, or where entry could cause damage or, in the inspector's opinion, pose a safety hazard.

It is the general opinion of the national associations and many of the states, that it is dangerous to the inspectors health to be exposed to extreme heat for prolonged periods of time.  Rules have been drafted into the SOP of each to protect the inspector and the buyer during the inspection process.

A recent discussion regarding inspections of attics in one of the national home inspectors forums:

I do not take random temperature readings of the attics I inspect. I do know that during the summer months attics in my area will hit 130f without any trouble. Once they get that hot I do not spend much time in them!  - Inspector from Tennessee

Location: Las Vegas, NV; single family, ranch style, home; south facing; reading of decking was south roof field; roofing material asphalt/fiberglass 3 tab shingles, one layer; approximately 10:30 A.M.; outside temp about 99 degrees.  I don't know what the air temp was in the attic but I didn't stay there very long either! - Inspector from Las Vegas.

I was in one last week and it was 189, let me see if I can find the pic.  Inspector from Utah

I also have recorded the 180 degree (upper) range in the attic when there has been very little wind movement and exterior temperatures exceed 115 degrees. No, you won't stay up there for long . . . Inspector from Las Vegas.

135 is common for me.  Inspector from Illinois.

In South Florida the typically daytime temperature might be 92 degrees to 95 degrees and the attic temperature might vary from 120 degrees for a tile roof to 140 degrees for a dark color shingle roof. - Inspector from South Florida.

As you can see from the inspectors comments that they are concerned about getting out of a hot attic as it can be dangerous to their health.  If you are looking for a thorough inspection, schedule it early in the day before attic temperatures reach extreme levels.  In the cooler hours of the morning inspectors are more likely to spend the necessary time in the attic investigating the systems you should be concerned with.

Frank Carr is the Owner / Inspector at First Choice Home Inspections in Deltona, FL serving Volusia, Seminole, Orange and Lake Counties. Formerly in the building trades, Frank’s focus is a safe home in the Orlando Metro and Daytona Beach areas of Central Florida and building FCHI. We believe that consumers have the right to expect the highest standards of thoroughness, fairness and effectiveness from their home inspector and that is exactly what we provide.
 

First Choice Home Inspections

Residential Home Inspections in Central Florida

(386) 624-3893 

Website:  http://1homeinspector.com

Facebook:  https://www.facebook.com/FirstChoiceHomeInspectionsLlc

LinkedIn:  https://www.linkedin.com/company/first-choice-home-inspections

Google+:  https://plus.google.com/+FirstChoiceHomeInspectionsDeltona

Twitter: https://twitter.com/1stChoiceHomeIn