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Let’s start with Crawlspace Basics

Vented vs. Unvented (Conditioned)

A Vented crawlspace is built with multiple foundations vents located in the perimeter walls of the crawlspace. These vents allow outside air into the crawlspace area. The traditional school of thought was by venting with outside air that would help control moisture and improve the overall air quality within the space. However, wall-vented crawl spaces can cause moisture buildup and other complications in households, especially in the Southeast.

An Unvented (Conditioned) crawlspace does not have vents – it is sealed against outside air infiltration. Think of the crawlspace as another room in your home – like a basement.

One of the most common terms used for creating an unvented crawlspace is “Encapsulation”. This type of crawlspace is insulated at the perimeter walls and not the crawlspace ceiling. To protect from ground generated water vapor a true “vapor barrier” must be installed. The vapor barrier must be properly sealed at the seams, edges, etc. so that vapor cannot penetrate into the crawlspace. You can “condition” the space by installing a properly sized dehumidifier.

The principal disadvantages of a vented crawl space over an unvented one are that (1) pipes and ducts must be sealed and insulated against heat loss (cooling loss in the summer) and freezing, (2) a larger area (the crawl space ceiling typically is larger than the area of the crawl space walls) usually must be insulated, which may increase the cost, (3) under hot humid conditions warm humid air circulated into the cool crawl space can cause excessive moisture levels in structural wood components (especially floor joists) that can cause mold and decay, and (4) an airtight, continuous thermal envelope at the crawl space ceiling is very difficult to achieve in practice.

· Credits: DOE Building Foundations Handbook, North Carolina Advanced Energy Corporation

Vapor Retarder vs. Vapor Barrier

A true vapor barrier must have a vapor permeance rating of less than .001. Typical builder grade 6ML black poly does not meet this requirement. It’s a vapor retarder not a vapor barrier.

Typical builder grade 6ML black poly is made from recycled content. This may sound environmentally friendly, but each time polyethylene is recycled, reground, etc. it loses its original performance characteristics. It will break down, turn brittle and not perform its role as a vapor retarder. It will need to be replaced several times during the life cycle of a home’s crawlspace.

Crawlspace Insulation

New Construction (Building Permit): First – always refer to the local building codes to determine what edition of the International Building Code they have adopted. For our area you have typically have a couple of options. Insulate between the floor joists of the crawlspace ceiling to R19 or insulate the perimeter walls of the crawlspace to R10.

There are several methods that could be used to achieve either of these requirement’s – the most common is R19 fiberglass batts between the floor joists of the crawlspace ceiling. You must present an insulation certificate that states the R-values of what was installed prior to receiving a Certificate of Occupancy.

Retrofit: There a couple ways to change or upgrade your existing insulation. You can DIY the install or hire a professional insulation install company. Either way, since a building permit is not involved, you may decide to install as you see fit. However, some words of caution, if you do not perform the installation to current building code standards this could really cause a problem down the road. An issue will most definitely arise if you decide to sell your home. Most every home sale requires a home inspection. Home inspectors are very up to date on current code requirements and will most certainly note any deficiency in the insulation on their reports. It will be a condition you must correct prior to the home selling.

Our Systems

encapsulation diagram

Encapsulation

The ultimate non-vented crawlspace system. Vapor Barrier will be the Viper CS 10 ML – Reinforced: White

Foundation vents will be sealed and insulated with Closed Cell Polyurethane Spray Foam. Exterior walls and rim joist of the crawlspace will be insulated and sealed with Closed Cell Polyurethane Spray Foam.

More About Encapsulation

Vapor Retarder:

A Standard Builder Grade Vapor Retarder System using Black 6ML Poly. The 6ML Vapor Retarder will be installed over the floor of the crawlspace and approximately 10″-16″ up the exterior perimeter walls of the crawlspace.

The Vapor Retarder will be mechanically fastened to the exterior perimeter walls for long term security. All seams will be taped using Black Seam Tape.

encapsulation diagram

Viper Reinforced Vapor Barrier

6.5 ML

Viper Reinforced 6.5ML White is a true Vapor Barrier System. The Viper 6.5ML Vapor Barrier will be installed over the floor of the crawlspace and approximately 10”-16” up the exterior walls of the crawlspace.

The Vapor Barrier will be sealed to the exterior perimeter walls of the crawlspace with Viper Double Bond Butyl tape. Once sealed to the exterior perimeter walls the Vapor Barrier will be mechanically fastened for long term security. All seams will be taped using a white Seam Tape approved for use in a crawlspace environment.

Key Performance Characteristics:

  • Permeance Rating – ASTM E96: .0095 Perms
  • Puncture Resistance – ASTM D6241: 255 LBF
  • Tear Resistance – ASTM D7004: 117 LBF

Viper CS 6.5ML Crawlspace Vapor Barrier warranty: ISI Building Products warrants, to the original Purchaser, crawl space vapor barriers manufactured by the Company. Viper CS will, for a period of 25 years, be free from defects in material and workmanship, under normal and proper use, storage, and operating conditions. Warranty details available upon request.

vapor barrier

vapor barrier

10 ML

A premium 10ML Vapor Barrier System featuring the Viper Reinforced White 10ML Poly. The Viper 10ML Vapor Barrier will be installed over the floor of the crawlspace and approximately 10″-16″ up the exterior perimeter walls of the crawlspace.

The Vapor Barrier will be sealed to the exterior perimeter walls of the crawlspace with Viper Double Bond Butyl tape. Once sealed to the exterior perimeter walls the Vapor Barrier will be mechanically fastened for long term security. All seams will be taped using a white Seam Tape approved for use in a crawlspace environment.

Key Performance Characteristics:

  • Permeance Rating – ASTM E96: .0016 Perms
  • Puncture Resistance – ASTM D6241: 626 LBF
  • Tear Resistance – ASTM D7004: 138 LBF

Viper CS 10ML Crawlspace Vapor Barrier warranty: ISI Building Products warrants, to the original Purchaser, crawl space vapor barriers manufactured by the Company. Viper CS will, for a period of 25 years, be free from defects in material and workmanship, under normal and proper use, storage, and operating conditions. Warranty details available upon request.

Why Viper for your Crawlspace Vapor Barrier?

The manufacturing of Viper CS starts with top-quality virgin resin which contains no recycled content. The resin then is converted into strands of polyethylene and formed together with a very tight hatch style pattern. The membrane that has been cross-woven is completed by coating the two sides with proprietary extrusion layers.

Viper CS is not like other products which contain reground or recycled plastic material as it is puncture and tear resistant when being installed and it won’t break down over the duration of time following installation.

cross woven

Cross-Woven

lifetime warranty

Lifetime Warranty

moisture barrier

Moisture Barrier

odor free

Odor Free

radon barrier

Radon Barrier

tear resistant

Tear Resistant
Designed for Crawl Spaces

For a clean and fresh look in your crawl space, Viper CS comes with a brilliant bright white color. This impressive vapor barrier is able to prevent detrimental effects that come from moisture, mold, mildew, and radon.

Having Viper CS installed correctly is essential when it comes to the long duration of powerful performance encapsulation projects. In order to provide the finest professional grade installations and best practices, ISI currently supports a distribution network as well as annual training opportunities.

Product Warranty

ISI Building Products
Lifetime Warranty
For Viper CS Crawl Space Vapor Barriers

Crawl Space Vapor Barrier & CrawlSpace Vapor Barrier Murfreesboro, TN, Brentwood, TN, Mt Juliet, TN, Nashville, TN, Columbia, TN & Franklin, TN

Vapor Barrier Maintenance Murfreesboro, TN | CrawlSpace Vapor Barrier Brentwood, TN | Vapor Barrier Replacement Mt Juliet, TN

Vapor Barrier ReplacementVapor Barrier ServiceVapor Barrier InstallationVapor Barrier RepairVapor Barrier Maintenance ∴ Franklin, TN ∴ Murfreesboro, TN ∴ Columbia, TN

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This entire experience was wonderful from beginning to end with this company. After they installed the foam the next morning my roommate and I both woke up and could immediately feel the difference in the main living area. Jeff explained every detail of how the process worked at point of sale and was patient with all of my questions after the fact. Freddy and his brother Henry were kind, professional, and friendly during the installation process. I couldn’t have asked for a better team for our first step in renovating the attic!

McKenzie H.

I needed to replace the insulation in my crawlspace. Jeff, at Complete Insulation, helped tremendously by discussing all my options and the pros and cons of each. They offered a competitive price and the installers did a great job. I highly recommend Complete Insulation!

Gerald R.

There aren’t many people like Jeff and Arnaldo in this world who are so passionate about their jobs. Jeff is so knowledgeable about insulation and is just such a nice guy. And the work ethic on Arnaldo is Amazing he moves with speed and efficiency. The before and after is amazing I am really impressed and couldn’t be happier with complete insulation.

Said A.

This company was professional from Day 1! Their bid was the lowest of all I gathered. Jeff Wells, their salesman, was very helpful! The installation crew arrived on time, was efficient, and kept my home clean. I would definitely recommend this company to anyone needing new insulation!

Ted S.

Complete Insulation excelled in every area. Jeff was quick to give an estimate on spray foam and blown insulation. He was extremely kind and impressionable. The day after I accepted their quote, Arnoldo and Mario were at my door ready with blown insulation. They, too, are a great representation of this company. I was impressed with their work and am so thankful they were able to install the insulation before the summer heat rolls in! I definitely recommend this company to anyone looking for insulation.

Savannah W.

We can already tell a difference in the “draftiness” of the house and the heat doesn’t seem to run as long even though it has gotten down in the 20’s in the evening. If you have the need for an insulation contractor, I couldn’t recommend Complete Insulation any more highly.

Patrick S.

I was building my own custom home and “interviewed” several spray foam insulators. It was clear Moody Ozier had a deeper knowledge of air sealing, R-value, and building codes than anyone else, so I went with Complete Insulation. He really took an interest in my hyper efficient build and came up with additional engineering ideas to further improve the efficiency of my home. I cannot say enough good things about Moody and Id tell anyone he’s trustworthy, efficient, and knows the insulation and air sealing business to great depth. Jose, Fredy, and their crews showed up on time, in uniforms, with clean trucks and did a wonderful job on instal AND cleanup. They were incredibly professional at every step and it was clear they had years of experience. I recommend Complete Insulation to anyone with encapsulation and/or insulation needs whether you are new construction, retro fit, investor, or otherwise.

Chad K.

Bravo. Insulation Complete is Complete Insulation. The 1937 house I purchased, had previous owners, who remodeled a crawl space or attic into a bedroom. The burning sun beating on the roof was excruciating. Jeff Wells, workmanship to spray insulate, was the solution. This action, provided a barrier that was essential for temperature control. Many thanks.

Judith F.

We had barrier and insullation replaced in the crawl space and the experience was great. Jeff was very informative and polite, couldn’t have asked for a better person to work with. The installation guys were great and it was complete in one day. The floors are warmer. The morning after the instsallation when I woke I could definately tell a difference in the air quality.

Carol R.

After calling several insulation companies and leaving messages and getting no responses I called Complete Insulation where a real person answered and assured me that they didn’t do business that way. Jeff Wells responded within a few minutes and was out promptly the next morning to look over our new home.
He was very personable and honest. He submitted an estimate that we felt was very fair. It was only a few days before a friendly and courteous crew was on site to install fiberglass batt in our walls. Jeff even recommended a drywaller who did our whole house. After the drywall was installed another great crew was out promptly to install the blow in insulation in our attic. The whole process was easy and it was a pleasure working with a company that is so responsive and does what they say they will do. I would definitely recommend Complete Insulation to fulfill your insulation needs.

Tim P.

I had a fire in my attic and needed all of the contaminated insulation removed. I am *AMAZED* at how thorough the hard working folks at Complete were. You could almost eat off the floor of the attic. The entire crew was courteous, quick and more than fair with the price. Highly recommend.

Derik H.

The team who came from Murfreesboro, TN to our house in Chattanooga were amazing. We have a very large home. They removed all the old insulation from our three attics, sprayed with a decontaminate and then sprayed all the new insulation. All in one very long day. They were great to work with, came went they said they would, answered all our questions. Had to put the tubes all the way from the attic down to the first floor and out to the truck. They covered all the floors, stairs etc and left the place spotless. We are very pleased and would highly recommend this company.

Lorraine F.
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