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This article is written to detail how to bury attic ductwork with insulation.  If your ductwork is metal, it’s likely laying on the attic’s floor already.  If it’s flexible ductwork, it’s likely hanging from straps above the attic’s insulation.  In many instances, it can be lowered to the attic floor.  But, there are several things that must be done to ensure the ductwork doesn’t sweat (condensation) as this will likely drip onto the attic floor — which are the ceilings of the rooms below.

Al’s Plumbing, Heating & A/C in Plano, Texas provides maintenance & repairs for all brands of; Central A/C, Gas & Electric Furnace, and Heat Pumps.  Additionally, we sell and install new HVAC Systems from; American Standard HVAC (same company as Trane), Ameristar, Standard), and Coleman HVAC (same company as York).

Al’s also provides full-service plumbing maintenance, repairs, and replacements for every plumbing component in your home.  Al’s sells and installs gas & electric water heaters.  Al’s is near your home in; Plano, TX; Allen, TX; and Frisco, Texas.  We service all homes in southern Collin county; Texas, and northeast Dallas County, Texas with no additional travel charges.

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.

We’ll Arrange An Appointment At Your Convenience.


If Your DFW Home Was Built In 1980 Or Earlier — Read Part 2 Of This Article First.

Click Here To Read Part-2 Of Our Article: AlsPlumbing.com Bury Attic Ductwork With Insulation – PART-2

 

In Part-2, We Go Into Great Detail About (pre-1980’s) DFW Homes With Original, Metal Ductwork That’s Covered With Asbestos Paper Wrap.

Asbestos Paper Wrap Was Added To Seal The Ductwork + Reduce Condensation.

 

PLUS: What (if anything) Needs You Should Do About Abestos Paper Wrap — it depends on the wrap’s condition.

 

Click Below To See A Pre-1980 Home’s Uninsulated Metal Ductwork Covered With Asbestos Paper Wrap.


Is It OK To Bury Attic Ductwork With Insulation In DFW?

YES — IF It’s Insulated to R-8 (or higher) AND Is Covered With A Vapor-Barrier

Click Here To See Uninsulated Metal Ductwork In An Attic: Uninsulated Metal Ductwork In An Attic

ductwork for hvac system

Image Source: Shutterstock

Shown: Uninsulated Metal Ductwork

We’ll Begin With A Brief Explanation About Why Uninsulated Metal Attic Ductwork Sweats In DFW (condensation). 

DFW’s Climate Is Called: “Humid, Sub-Tropical“.

Humid, Sub-Tropical Climate Is Described As:

  • Humidity is high during the summer.
  • During June — August, DFW’s Dewpoint averages around 70 degrees.
  • This means when the outdoor temperature drops below 70 degrees — Dew will form (like on cars and grass).

Attic Ductwork In Humid Climates (like DFW)

When & Why Attic Ductwork May Sweat

  • During much of DFW’s Air Conditioning Season (May-Sept) — DFW’s Average DewPoint = 70 degrees (+/- 10).
  • When A/C runs — HVAC ductwork’s surface temperature drops to 50-55 degrees.
  • When the Dewpoint = 70 Degreescondensation forms on surfaces with a temperature below 70 degrees.

Source: https://insulation.org/io/articles/condensation-control-why-the-proper-insulation-choices-will-keep-you-out-of-the-rain/

Click Here To See Metal Ductwork With Condensation At The Bottom: Sweating Metal Ductwork

Humidity Definitions

Relative Humidity: Stated As A Percentage – The amount of humidity in the air — compared to the total amount of humidity the air could hold at that temperature.

  • Warmer air holds more humidity (than colder air) —  because warm air is less dense (than cold air).
  • With no change in humidity — Relative Humidity goes down as air gets warmer.
  • With no change in humidity — Relative Humidity goes up as air gets cooler.

At 100% Relative Humidity: 

  • The air is holding as much moisture as possible at that temperature.
  • It doesn’t require rain to be falling.
  • When the temperature and dew point are the same — relative humidity = 100%.

dew drops on car

Shown: Dew that has formed on an outdoor surface.

Image Souce: Pixabay

As Compared – DEWPOINT:  Stated As Degrees – The actual amount of humidity in the air without regard to air temperature.

  • Whenever the air temperature drops below the Dew Point Temperature — Dew/Condensation forms on surfaces (like grass and cars).

Source: https://www.weather.gov/lmk/humidity


In DFW, it’s common practice to hang flexible ductwork above the attic floor.  During summer, DFW attics can reach 170 degrees.  Hanging attic flex-duct (per building code) must have R-8 insulation + a vapor-barrier.  Hanging ductwork above the attic insulation ensures that it stays dry (because attic heat dries it) — but that comes at the cost of higher cooling & heating bills.

Click Here To See An Infrared Image Of An Attic During Sumer — Attic Temp = 170 Degrees

Attic Infrared Image Shows 170 Degrees

Shown: R-8 Insulated Flexible Ductwork — With Outside-Jacket As A Vapor-Barrer.

Image Source: Amazon.com Embedded Link

Click On Image To; View Product, Read Details, or Purchase From Amazon.com

Insulated, Flexible HVAC Duct Consists Of:

  • Interior vinyl tube supported by a spiral, metal coil (product shown above also has a cloth mesh covering the inner tube.
  • The interior tube is surrounded by fiberglass insulation (R-8 or more in DFW).
  • The insulation is covered with the outer vinyl cover that serves as a vapor-barrier.
  • Today’s flexible ductwork meets vapor-barrier requirements.


A Scientific Study Was Performed By

Home Innovation Labs In South Carolina’s

Warm & Humid Climate (similar to DFW’s)

The Question: When Ductwork Is Buried In Attic Insulation — Is There Potential For Condensation To Form On Its Exterior

In Humid Climates (like DFW) During The Cooling Season.

Ductwork Definitions:

  • Furnace Plenum: It’s the begging of the ductwork — and is attached to the furnace.
  • Note: The Ductwork’s Trunk Line Attaches (to the other end) of the Plenum.

hi-e gas furnace

Image Source: CanStockPhoto

Shown: Furnace Plenum (behind the vertical white pipe & diagonal black pipe).

  • Trunk Line: (starts at the plunum): It’s a larger duct that supplies air to Branch Lines.
  • Branch Line: (starts at the trunk line) — Branch(es) Serve Each Room.
  • Boot: (c0mes through the ceiling — and connects the Branch line (in attic) TO The Register (inside the house).

flexible

Image Source: Shutterstock

SHOWN: Trunk Line: The largest of the round pipes visible.

SHOWN: Branch Line: The smaller of the round pipes visible.

SHOWN: Boot:  The Rectangular Piece — connected to the branch line.

  • Register: What you can open & close.

heat vent register cover

Image Source: Shutterstock

SHOWN: Register

Copy The Link Below Into Your Browser To Read The Original Home Innovation Labs’ Report.

https://www1.eere.energy.gov/buildings/publications/pdfs/building_america/compact-buried-ducts-hot-humid.pdf

Page 47 of 61: Shows The Attic Ductwork During The Home’s Construction

NOTE: Photos Below Are Representative Of What The South Carolina Home’s Attic Ductwork Looked Like.  Photos are of another home studied.

  • Figure 15: Shows The “Trunk” Line (definition above) — Was Encapsulated In Spray Foam (because it’s too large to bury in insulation).
  • Figure 15: ALSO Shows The (gray) “Branch” Lines (definition above).  They are compact, flexible ductwork with no modifications.
  • Figure 16:  Shows The Attic After The “Branch” Lines Were Buried In (blown, fiberglass) Attic Insulation.

The Study’s Goals

1. Develop criteria for ductwork (buried in attic insulation) that:

  • Uses common building materials.
  • Does not require ductwork to be encapsulated (surrounded) with spray foam — to prevent condensation.

2. Establish criteria to bury (compact, flexible ductwork) — to reduce energy losses (caused by ductwork being hung above attic insulation).

3. Develop guidance to help determine the reduced heating & cooling needs — due to compact ductwork buried in attic insulation.

The Subject Home is located in Lady’s Island, South Carolina.

Lady’s Island is roughly halfway between Savannah, GA & Charleston, SC.   It’s quite near the ocean, which explains the quite high Dew Point.

Test performed during August.  Typical Dewpoint: Near 80 degrees (+9 over DFW)

The Study’s Findings

NOTE: 37 Sensors Monitored; Temperature, Relative Humidity, & Dew Point At These Locations;

  • Outdoors
  • Inside The Attic
  • Inside The Living Space – at the ceiling.
  • Outdoor Temperature approached 95°F.
  • Outdoor Dew Point approached 80°F.
  • Attic temperature peaked near 120°F.
  • Attic Temperature Sensors (spaced at 3.5″, 6″, & 8.5″ above the attic floor) — varied by up to 15°F (daytime) and 3-5°F (nightime)

Dew Point Was Measured:

  • Outdoors
  • Inside the attic (above the attic insulation).
  • Within (inside) the attic insulation.
  • At a Supply-Air Duct Boot (connects air coming from the Branch Line to the register vent inside the house) located near a ceiling.
  • A/C produced cooled air at 55°F

(As Compared To August In DFW):

  • Average High Temperature = 97.5F.
  • Average Dew Point = 71°F.
  • DFW attic temperature can reach 140°F+ on a 95°F day.  Attic temperature is higher during full sunshine AND lower during full clouds.
  • Properly operating Central A/C produces air that’s up to –20°F — lower than the thermostat’s setting.

Source: https://www.wunderground.com/history/daily/us/tx/dallas/KDAL/date/2021-8-15

Source: https://www.radiantguard-psg.com/live-attic-temperatures-frisco-tx/

The Study’s Conclusions

  • Outdoor Dew Point approached 80°F.
  • Dew Point (inside the attic, above the insulation) = 68°F — 80°F during most of the day.
  • Dew Point (at the register — in the room’s ceiling & under the insulation) = 58°F To 68°F.
  • Dew Point at the register was10°F To -12°F lower than above the insulation.
  • Dew Point within (inside) the attic insulation was notably lower than the attic’s dew point (above the insulation).
  • No condensation was measured nor observed along the ducts.
  • Near the ducts (buried inside attic insulation) — there was No strong risk of condensation.

NOTE: This Research Study’s Conclusions (plus another source shown just below) Counters Common Opinions That Attic Insulation Doesn’t Lower Humidity.  

Another Source:

  • High-quality insulation offers enhanced humidity control.  Insulation is able to help keep moisture out of your home.
  • With the vapor-retarder ability of insulation materials — the amount of moisture able to transfer into your home is reduced.

Source: https://www.homelogic.co.uk/does-insulation-help-with-humidity-the-definitive-answer

Copy The Link Below Into Your Browser To Read The Entire Report — That We Summarized Above.

https://www1.eere.energy.gov/buildings/publications/pdfs/building_america/compact-buried-ducts-hot-humid.pdf

(Conclusions Begin On Page 30)


Perm Rating Definitions:

  • Perm Rating: Represents how much humidity can pass through a material.
  • The lower the Perm Rating — the less moisture can pass through it.
  • A Vapor-Barrier prevents humidity from passing through it.
  • A Vapor-Retarder slows humidity passing through it.

PERM Rating:

  • <.1           Class I—-  Impermeable                    Example: Polyethelene (plastic) sheeting.
  • .1 0 – 1.    Class II — Low Permeability            Examples: Paper-faced fiberglass batt insulation (Perm=1).
  • .1-10.00  Class III — Permeable                        Examples: Unfaced Batt & Blown Fiberglass insulation.
  • > 10.        Class IV — Highly Permeable           Example:   Drywall: Perm 50.

Source: https://www.aepspan.com/high-permeability-underlayment-blog/

  • Blown Fiberglass Insulations Perm Classification: Class III-Permeable.   
  • This classification shows that blown fiberglass insulation has some vapor-retarding ability.
  • This Explains The Study’s Findings — that DewPoint within (inside) the attic insulation was notably lower than (above) the insulation.

Source: https://www.buildinggreen.com/sites/default/files/BG_Insulation_Recommendations.pdf

Sources: 

  • (Report): U.S. Department of Energy Building America Program
  • (Study Performed By): Home Innovation Research Labs
  • (url) https://www1.eere.energy.gov/buildings/publications/pdfs/building_america/compact-buried-ducts-hot-humid.pdf    PAGE 16


Can An Existing Home’s

Hanging Flex-Duct Be Moved To The Attic Floor — Then Bury Attic Ductwork With Insulation

At Present, Texas Building Code Is Based On The 2012 International Residential Code (IRC).

The 2012 IRC Did Not Allow Attic Flexible Ductwork To Be Buried In Insulation.

NOTE: Any Texas Municipality May Choose To Exceed Texas’ State Building Codes.

Many Texas Municipalities Have Adopted The 2018 or 2021 IRC Codes.

Call Your Municipality To Confirm If You Violate Their Building Codes If You Move Ductwork To The Attic Floor & Cover It With Insulation.

 

Beginning With The 2018 International Residential Building Code (IRC)

Flex-Duct Is Allowed To Be Buried Within Attic Insulation In Humid (Climate Zones 1–3 DFW is in 3).

  • The IRC requires a minimum of R-13 (attic insulation on top of the flex-duct — in addition to the flex-duct’s attached insulation.
  • This is to prevent ductwork condensation in humid climates (including DFW).

NOTE: To constantly adapt Building Codes to innovations in Building-Materials (what it’s built of) and Building-Science (how it’s built) –The IRC is updated every 3 years.  When this article was written, the 2021 IRC had been adopted.

At Present, Texas Building Code Is Based On The 2012 International Residential Code (IRC)

On June 7, 2021: Governor Greg Abbott signed Texas House Bill 738 – which amends sections of Texas’ Local Government Code — and establishes these as the statewide codes for residential construction in Texas.  The 2012 IRC Does Not Allow Ductwork To Be Buried In Attic Insulation.

  • 2012 International Residential Code (IRC)
  • 2012 International Building Code (IBC)

Source: https://www.prnewswire.com/news-releases/international-code-council-celebrates-updates-to-texas-statute-for-building-and-residential-codes-301323137.html


These Details Discuss Attic Ductwork Installation On The Attic’s Floor

So You Can Bury Attic Ductwork With Insulation

roof trusses

Image Source: Shutterstock

Shown: Attic Trusses

  • Ideally, the ductwork should lay on the attic floor (the ceilings in the rooms below are attached to the attic’s floor).
  • Running ductwork on the attic floor — typically means it’s sitting on the bottom board of attic trusses (trusses shown just above).
  • Choose From; metal, flex-duct, or fiber-board ductwork.
  • Ductwork must be insulated to R-8 or higher (DFW building code).
  • The duct insulation must also include a vapor-barrier cover.  Note: Today’s flex-duct has a vapor-barrier.
  • Mastic-seal all duct connections to prevent air leaks.
  • Install loose-fill (blown) insulation to cover the ducts + the attic floor — to Texas Code of R-38 or higher (DFW building code).
Copy The Link Below Into Your Browser To See Attic Flex-Duct Being Installed On The Attic’s Floor

Click Here To See Flex-Duct Being Installed On The Bottoms Of Attic Trusses:  Flex Duct Installed On Bottoms Of Attic Trusses

Photo Source: “Professional Builder” Magazine.  A trade-magazine that’s published for new home builders.

Notes: The bottoms of attic trusses are at the attic’s floor.  The bottoms of attic trusses are what the drywall ceilings below are attached to.

Common Problems With (hanging) Flex-Duct — Are Caused By Improper Installation

  • Improperly supported flex-duct will sag.
  • This increases air resistance & slows airflow.
  • Flex-duct supports can be up to 48 inches apart.
  • Attic trusses are installed up to 24 inches apart.
  • Flex-Duct, installed on the attic floor (versus hanging) — has up to twice as many points of support.
  • Flexible ducts may rest on attic trusses — everywhere flex-duct support requirements are met.

AND

  • Flex-duct, installed on the attic floor, can be buried in attic insulation.

SOURCES:

  • https://basc.pnnl.gov/resource-guides/support-intervals-flex-ducts
  • https://www.energyvanguard.com/blog/buried-ducts-allowed-2018-building-code
  • https://codes.iccsafe.org/content/IRC2018/chapter-16-duct-systems

NO: You Cannot Bury (original, uninsulated) Metal Ductwork With Attic Insulation.

ductwork for hvac system

Image Source: Shutterstock

Shown: Uninsulated Metal Ductwork

If you bury uninsulated ductwork in attic insulation — it’s likely it will sweat (condensation).

Dust (in the insulation) + condensation may cause mold in the attic.

AND condensation may drip off the ductwork onto the ceilings below.  Over time, this may cause water damage & mold to ceilings.

NOTE: It’s rare for metal ductwork to be insulated on the inside.  Dust in the HVAC’s airstream would stick to interior ductwork insulation.  It would also prevent the ductwork from being cleaned.

 

YES: You Can Bury (original, uninsulated) Metal Ductwork With Attic Insulation

AFTER It’s Insulated (R-8 or higher) + A Vapor-Barrier Is Added.

OR The Ductwork Is Encapsulated (surrounded) With Closed-Cell Spray Foam.

Copy The Link Below Into Your Browser To See (hanging) Flex-Duct That’s Encapsulated With Closed-Cell Spray Foam:

https://www.google.com/search?q=insulating+ductwork+with+spray+foam&sxsrf=APq-WBv_k8lCDPjX3jIzgg-jbTdFrA8lxg:1643645878024&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiriciFstz1AhVonWoFHerrAOwQ_AUoA3oECAEQBQ&biw=960&bih=484&dpr=2#imgrc=CGsVORKysky8rM

 

NOTE: You Can Wrap Uninsulated Metal Ductwork With Insulation + Vapor-Barrier Products Specially Made For That Purpose. 

See A Sample Product Below.

NOTE: Many Of These Products Include A Vapor-Barrier (required)

Image Source: Amazon.com Embedded Link

Shown:

Click On Image To; View Product, Read Details, or Purchase From Amazon.com

NOTE: This Product Has A Foam-Core Between Two Outer Foil Layers.   It’s Not: “Bubble Wrap”.

The Manufacture’s Website Says:

    • 1/4″ (5 MM) thick.
    • A layer of Closed-Cell Foam — is bonded between 1 layer of highly-reflective, metalized-aluminum, polyester film — on each side.
    • Reflects 97% of radiant heat.  Rejects the sun’s heat inside the attic — during summer.
    • Emits less than 3% of heat from ducts during winter.
    • Not affected by moisture or humidity.
    • Inhibits condensation.
    • Does not promote the growth of; fungi, mold, or mildew.
    • Hold it in place with; staple, nail, glue, or spray-adhesive.
    • Does not compress, collapse or disintegrate.
    • Class 1 / Class A Fire-Rated radiant barrier that has passed the ASTM E84 test & ASTM E259.

Source: https://www.usenergyproducts.com/products/R-8-hvac-duct-wrap-insulation-reflective-2-sided-foam-core-4-x-125-500-sq-ft

NOTE:

  • This product can be used to cover uninsulated metal ductwork.
  • All 4 sides must be covered.

NOTE: Foil-Wrap Insulation Must Be Attached To The Ductwork. 

One way to attach it is with spray glue.  Below is one of many brands.  Gorilla brand products have an excellent reputation for performance.

Note: This brand of spray glue works very well.  It’s unlikely you can pull the insulation off to reposition it.

Image Source: Amazon.com Embedded Link

Shown: Gorilla Brand Spray Adhesive.

Click On Image To; View Product, Read Details, or Purchase From Amazon.com

 

Image Source: Amazon.com Embedded Link

Shown:

Click On Image To; View Product, Read Details, or Purchase From Amazon.com

NOTE: Use Metal-Foil Tape At The Foil Insulation’s Seams. 

Don’t Use (cloth) Duck Tape — DFW Attic Heat Causes That Product To Fail In A Short Time.

 

NOTE: To Make This Installation Easier & Faster — Wrap The Ductwork Around Corners Wherever Possible.

It Reduces The Number Of Foil-Tape Seams That Must Be Installed.

Note: Al’s Plumbing, Heating, & A/C Does Not Endorse Any Specific Brand Of; Ductwork Insulation, Metal-Foil Tape, or Spray Adhesive.

Only Because We Don’t Have First Hand Knowledge Of All Products Available.



On Another Note: In Older DFW Homes — Metal Ductwork Was Poorly Or Not Sealed (for leaks).

According To The EPA ENERGY STAR® Program:

  • Duct leakage should be less than 5% in a newly installed HVAC System.
  • A typical home leaks 20% of cooled/heated air through leaking ductwork.
  • In older homes, it is not uncommon for duct leakage to be 30%-50%.

In Older DFW Homes:

  • Ductwork sealing products could not hold up summer attic temps (up to 170 degrees).
  • Early sealing products (like duck tape) — failed in as little as a few days.
  • In a Houston, TX study: The cost to seal ductwork (for a 1,650 square foot home) — ranged from $575-$2,675.
  • In that same study — sealing ductwork reduced annual cooling/heating costs by $200-$400 per year.
  • Ductwork Sealing Payback Period= 2.5 years To 7 years.
  • The Duct-Sealing price range depends on the type of sealing performed.
  • Sealing can be done inside the ductwork (details below) OR outside the ductwork.
  • Cost is much lower with inside ductwork sealing.

Source: U.S. Dept. Of Energy  https://www.nrel.gov/docs/fy12osti/53494.pdf


Exterior Ductwork Sealing Can Be Done Inside The Attic

But There’s A Simpler & Less Expensive Solution. 

Airborne (inside) HVAC Duct Sealant

Image Source: YouTube Embedded Video

Shown: A Demonstration Of Aeroseal Duct Sealing System.

NOTE: Al’s does not endorse any specific ductwork-sealing system — only because we don’t have first-hand knowledge of every system.

A Google search will provide contractors in your area.

 

Here’s How Airborne (inside) Ductwork Sealing Works

  • First, the ductwork is cleaned.

Click Here To See A Before & After Ductwork Cleaning Photo: Before & After Ductwork Cleaning

Next:

  • Air registers (can be shut off) and grilles (can’t be shut off)– are covered with plastic
  • An airborne polymer mixture is injected into the ductwork under high air pressure.
  • This polymer remains airborne — until it encounters a leak.
  • At leaks, the polymer’s particles begin to exit at leaks.
  • Then, the particles stick together and seal the leak.


This Information Is Not For DFW.   

It Applies To Some Areas Of The U.S.

For Homes Built Up To The Early 1980s

With Ductwork Located Under The Slab Foundation. 

Some Of The Ductwork Is Made Of Concrete That Contains 15-25% Asbestos. 

If it’s not been painted — A Black Stamp Reads: “JM-TRANSITE”.

Click Here To See A JM-Transite Stamp: JM Transite Stamp

Click On Link To See Transite Ductwork Under A Slab Foundation: Transite Ductwork Under A Slab Foundation

  • Transite was created in 1929 — for asbestos-concrete building materials.  Transite™ is a Trademark of Johns-Manville Corporation.
  • The word: “transite” is often (generically) used to describe products made of asbestos-cement.
  • Transite ductwork was popular in SOME 1960s & 1970s homes — that have HVAC Ductwork under their slab foundation.
  • These homes’ heat vents are in the floors.  No attic ductwork homes have Transite.  It’s made of concrete, and would be too heavy.
  • Some people describe: “under-slab ductwork” as “transite”.   This is an incorrect use of the word.

NOTE: Most under-slab ductwork is NOT Transite.

Source: https://inspectapedia.com/hazmat/Asbestos_Transite_Ducts.php

Transite Ductwork Creates The Risk Of Asbestos-Fibers Being Released Into The Home’s Indoor Air.   

If Removed — Transite Ductwork Removal Must Be Performed By A Qualified Asbestos-Abatement Contractor.

NOTE: MOST IN-SLAB DUCTWORK IS NOT TRANSITE. 

A Home Inspector Can Determine Which Material(s) Your Home’s Ductwork Is Made Of.

Source: https://www.snipsmag.com/articles/94147-are-sub-slab-hvac-ducts-problematic

NOTE: IT’S DANGEROUS TO HAVE TRANSITE DUCTWORK CLEANED.

CLEANING DISTURBS THE INTERIOR SURFACE,

WHICH MAY RELEASE ASBESTOS FIBERS INTO THE AIR


NOTE: Some Companies State That They Can Spray A Product Inside Transite Ductwork To Reduce The Risk Of Airborne Asbestos.

Because DFW Homes Don’t Have Under-Slab Ductwork,

 We Have No First-Hand Knowledge Of These; Products, Services, or Contractors.

A Google Search May Locate Contractors In Your Area.



Mesothelioma Is A Form Of Cancer Caused By Inhaled Asbestos Fibers.

Mesothelioma Tumor(s) Can Form In The; Lungs, Abdomen, or Heart.

When anything containing asbestos is disturbed — microscopic asbestos fibers are released.  These fibers can remain airborne almost indefinitely and can travel great distances.

Asbestos Materials Are Either:

Nonfriable:

  • Durable products keep asbestos fibers safely contained — as long as the materials are not damaged.
  • Vinyl Asbestos (VAT) Floor Tile is one.
  • Removing VAT Tile safely must be done by a qualified Asbestos-Abatement Contractor.

Friable:  Easy to break or crumble by hand.

  • Friable asbestos materials easily release asbestos fibers into the air.
  • Damaged or Deteriorated asbestos ductwork or pipe insulation would be an example.

Prior to 1978 — Asbestos May Have Been Used In The Manufacturing Of:

  • Assorted types of insulation
  • Wallpaper
  • Linoleum floor tiles and sheet flooring (1 large piece).
  • Linoleum sheet flooring poses a significantly greater risk than floor tiles or wallpaper.
  • Because it was often made with a friable asbestos backing (easily sheds asbestos fibers).

Source: https://www.asbestos.com/products/vinyl-products/

Inhaled Asbestos Fibers Can Become Permanently Lodged Inside The Body — And Pose Serious Health Threats. 

  • Asbestos is known to cause disease and cancers — and symptoms may not appear for up to 20 or more years later.
  • There is no known safe level of asbestos exposure.
  • Thousands of tradesmen who worked with asbestos-containing building-materials have died of related diseases.
  • Even though the use of asbestos is now limited in the U.S. – thousands continue to die each year — due to past asbestos exposures.

Source: https://www.iowadnr.gov/portals/idnr/uploads/air/insidednr/asbestos/asbest_reg_brochure.pdf

Source: https://www.asbestos.com/mesothelioma/

Source: https://www.asbestos.com/blog/2018/07/13/asbestos-floor-tile-diy-removal/

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This article is written to detail how to bury attic ductwork with insulation.  Al’s Plumbing, Heating & A/C in Plano, Texas provides maintenance & repairs for all brands of; Central A/C, Gas & Electric Furnace, and Heat Pumps.  Additionally, we sell and install new HVAC Systems from; American Standard (same company as Trane), Ameristar, Standard), and Coleman HVAC (same company as York).

Al’s also provides full-service plumbing maintenance, repairs, and replacements for every plumbing component in your home.  Al’s sells and installs gas & electric water heaters.  Al’s is near your home in; northeast Dallas, TX; Richardson, TX; and Garland, Texas.  We service all homes in southern Collin county Texas and northeast Dallas County, Texas with no additional travel charges.

Call Al’s today to discuss any concerns or problems you have with your HVAC System or Plumbing.

We’ll Arrange An Appointment At Your Convenience.