What is crawl space encapsulation? 10 things you should know before you begin!

Posted on: January 9th, 2013 by

As a Crawl Space Encapsulation contractor we verify that crawl space encapsulation is the correct application as it is NOT a total solution for every crawl space. Below are 10 considerations to take into account for each individual crawl space.

1)      High Humidity Levels? (Look for water leaks, ground water, normally high relative humidity because of vented crawl space.)

2)      Unsealed mechanicals in crawl space? (This can effectively suck unhealthy crawl space air into return ducts and redistribute to living areas.)

3)      Dirt or gravel floor? (Humidity levels from 50% to 90% are easily found in dirt/gravel crawl spaces, 55% is enough to support the growth of harmful Black Mold, fungi, and microorganisms.)

4)      Vents in crawl space? (Vented crawl spaces allow relative humidity levels from outdoors to add to already high humidity levels in a crawl space leading to growth of mold, fungi, and other microorganisms. This air also carries dust, pollen, and other allergens.)

5)      Poorly installed plastic vapor barrier? (A sheet of plastic lying on the ground is not enough to keep ground moisture from entering the crawl space. Standard plastics are not sealed at the seams or perimeter walls, they develop dry rot, and are not strong enough to withstand foot/crawl traffic.)

6)      Is the crawl space conditioned? (The crawl space should be conditioned like any other room in the house, you don’t leave your basement windows open in the winter, and your crawl space is no different. A dehumidifier may still be needed after encapsulation to keep the relative humidity below 50%)

7)      Rodent issues? (If your crawlspace is infested by rodents, no thickness of liner material will stand up to the jaws of burrowing rodents.)

8)      Falling, wet, and moist fiberglass insulation? (Fiberglass insulation becomes heavy from the relative humidity and will fall to the moist ground where it becomes be a haven for mold, mildew, fungi, and other microorganism growth.)

9)      Hydrostatic pressure? (Is there is a high water table or water that is hydrostatically forced from the ground or crawl space walls? The introduction of a perimeter drain tile system with a sump pump may be required.)

10)   The “Stack Effect”? (When warm air rises and escapes from your living area it creates negative pressure and causes a sucking effect to replace the displaced amount of air. A typical crawl space can contribute up to 40% of the air replaced by the stack effect.)

Before we start a crawl space encapsulation, we do a ground up inspection of the existing conditions. We’ll evaluate the crawl space for higher than normal humidity levels and determine if a drain tile system is needed. It makes no sense to cover up a water issue without addressing the cause. Additionally, we’ll look for mechanicals that may be adding humidity to the crawl space; is there an air conditioning unit with faulty drainage, a leaking plumbing pipe, a bathroom with a leaking shower/bath? We will also look for evidence of rodents that may have burrowed under the foundation and into the crawl space. This may call for the introduction of a “Rat Slab” to prohibit their return into a newly encapsulated crawl space.

Looking up the walls, we’ll determine if there are active foundation cracks that may be letting water in by hydrostatic pressure. Are there open vents around the crawl space letting unconditioned air in from the outside?

Looking further up, we’ll determine if the floor joists are sagging or rotten from the exposure to years of high humidity levels. Is there damaged insulation that needs to be removed? Is there mold growth on the underside of the floor sheathing? All of these issues need to be addressed and remedied before any work begins.

If the project is in a frost prone region like Chicago, we recommend insulating the walls with SPF or Spray Polyurethane Foam. The Closed Cell spray foam is air impermeable and a rated vapor barrier. We will lay out a cross woven, puncture resistant, and UV stable plastic membrane over the dirt/gravel floor and lap the ends about a foot up the perimeter walls (these will be spray foamed to the wall later to seal the top seams). Any overlapped seams or penetrations will be sealed with a manufacturer approved seam tape to seal these areas. Any vents will be closed and sealed off permanently. Then spray polyurethane foam is sprayed on the concrete or brick walls and into the joist pockets around the rim joists). The area of the rim joist can account for up to 17% of the heating and cooling cost due to air infiltration. It will also make cold floors above the crawl space disappear.

After the encapsulation is complete, it is a good idea to monitor the crawl space for humidity fluctuations. Sometimes it’s necessary to introduce a vent into the crawl space to regulate humidity and in extreme cases, a dehumidifier may be in order to keep humidity to a minimum.

Houses that are NOT good candidates for crawl space encapsulation include; houses in a flood plane, houses built on piers, mobile homes with a skirting, enclosed porches without a continuous foundation. A good solution for properties described above is spraying closed cell spray polyurethane foam insulation to the underside of the first floor living space and floor joist. This will seal off any moisture/ air infiltration into the living area and be a FEMA approved material in a flood plane.

What is R-value for Spray Foam Insulation vs. Fiberglass Insulation?

Posted on: November 21st, 2012 by

Being in the Chicago spray foam insulation market, this question comes up a lot when comparing spray foam insulation to fiberglass. To understand R-value, you need to understand the ASTM 518 testing performed in a lab AND how the materials actually perform in the real world outside of the lab. The effects outside the lab that are not incorporated into the testing include: thermal bridging, air movement, air infiltration, thermal mass, moisture content, solar radiation, and performance at various temperatures. What is tested is conduction of energy from one plate through the test material (insulation) to another plate. Conduction is one of three ways heat moves, convection and radiation are the other two which are not tested in R-value.

Studies done by independent research facilities funded by the US Department of Energy have shown that fiberglass loses 8% of its R-value before it’s installed. When perfectly installed with access on both sides of a stud wall to ensure all six sides of the insulation sit square and are in contact with all surfaces, fiberglass loses 11% of its stated value. When commonly installed it lost 28% of its stated R-value in a completed wall assembly. This study did include thermal bridging but did not take into account air infiltration, moisture, and greater temperature differences which would reduce this number even more.

Spray foam insulation has shown to eliminate air movement and air infiltration which address convective currents in the wall cavities along with moisture. When tested at greater extremes than the ASTM 518 calls for, spray foam maintains its R-value and as temperatures drop, spray foam insulation actually preforms better than its stated R-value. Spray foam also reduces the effects of solar radiation and when thought has been put into wall framing, thermal bridging can also be addressed making SPF a logical choice in super insulating homes.

R-19 Fiberglass actual performance with lower climate temperatures.

Loose Fill Fiberglass

Metering Chamber (F)

Climate Temperature (F)




















How Much Money Does Spray Foam Insulation Cost?

Posted on: October 24th, 2012 by

The first question our clients ask us as a spray foam insulation contractor is “How much does spray foam insulation cost?” The answer is simple if you know the math behind the figures. Spray foam also referred to as Sprayfoam is normally calculated by a volume called the Board Foot which is 12″ Wide x 12″ Long x 1″ Thick.

The next part of the equation is based on the desired foam qualities and desired thickness which will determine the R-Value. There are two types of spray foam insulation commonly used, “Open Cell” and “Closed Cell“. These foams have different densities (contributing to R-value) and water repelling qualities. Quick examples are; Closed Cell can be used in below grade environments or where contact with water is likely/possible, i.e. basement or where high R-value is needed in a min thickness. Open Cell insulation is great in areas not exposed to moisture and where thickness is not an issue i.e. 2×4 framing and thicker for walls and 2×8 and thicker in an attic or roof assembly.

So after figuring out what type of foam is called for and the thickness needed for a desired R-Value we’re ready to figure out the volume. A quick example would be a 10′ wide wall(W) that stands 8′ tall(L) which has a cavity to be sprayed at 3-1/2” Thick(T) or 10 x 8 x 3.5 = 280 Bd Ft (board feet). We then need to multiply this number by the installed cost of the material per board foot. This number (based on Nov-12 prices) ranges from $0.45 – $0.60 per board foot for “Open Cell” and is based on the amount of prep, waste, trimming, hard to reach places, and other influencing factors. Closed Cell is priced anywhere between $0.98 – $2.00 a Bd Ft depending how confined the space is, i.e., a crawlspace, under a porch, the outside of a foundation wall, as well as the previously mentioned influences. There are other factors that can play into a quoted price like the size of the project. A small project may be on the higher side of the spectrum while a larger project on the lower. Some sprayfoam insulation contractors in the Chicago market have minimum charges.

We hope that this information is helpful in applying a general budget to your upcoming project. If you have any questions, please “Contact Us”

How Much Money Will I Save? & What’s the ROI?

Posted on: October 4th, 2012 by

Here in the Chicago spray foam insulation market, we are often asked how much money will I save and what is the return on investment? The answer is; How much money are you willing to throw out the window if you don’t insulate with spray polyurethane foam insulation? Our average customer saves over 50% on their heating and cooling.

The average stock market return was calculated at 8% a year when the economy was good. Chicagoland Spray Foam Insulation products could create a return on investment near 33-50% a year. Meaning your payback would be in 2-3 years at the current Chicago-land gas and electric rates. If rates continue to increase, as they always do, your return could be accelerated. After the initial investment, it’s “Money in the bank”.

Some other considerations that are commonly overlooked when factoring in the price of spray foam insulation are; Comfort, elimination of drafts make a home feel much warmer. A home where condensation is not allowed in walls eliminates harmful mold spores from festering. Less fossil fuel use is environmentally friendly and reduces harmful pollutants.

Service Area

Posted on: September 24th, 2012 by

Chicago and Chicagoland service area includes all surrounding suburbs such as Evanston, Wilmette, Kenilworth, Winnetka, Glencoe, Highland Park, Highwood, Lake Forest, Lake Bluff, North chicago, Zion, Winthrop Harbor, Oak Park, River Forest, Elmwood Park, maywood, Melrose Park, Berkeley, Bellwood, Northlake, Westchester, Elmhurst, Addison, Villa Park, Lombard, Glendale Heights, Carol Stream, Oakbrook Terrace, Glen Ellyn, Wheaton, Winfield, West Chicago, Licolnwood, Morton Grove, Golf, Glenview, Skokie, Northfield, Bannockburn, Deerfield, Lincolnshire, Mettawa, Green Oaks, Cicero, Berwyn, Riverside, North Riverside, Westchester, Countryside, Hinsdale, Clarendon Hills, Oak Brook, Westmont, Darien, Norridge, Park Ridge, Des Plaines, Mt. Prospect, Arlington Heights, Palatine, Rolling Meadows, Inverness, Barrington, Barrington Hills, North Barrington, Tower Lakes, Fox River Grove, Cary, Algonquin, Lake in the Hills, Summit, Bridgeview, Justice, Burr Ridge, Willow Springs, Lemont, Park Ridge, Wheeling, River Grove, Rosemont, Wheeling, Buffalo Grove, Vernon Hills, Mundelein, Round Lake, Round Lake Beach, Round Lake Heights, Round Lake Park, Lake Villa, Burbank, Evergreen Park, Oak Lawn, Chicago Ridge, Blue Island, Robbins, Midlothian, Oak Forest, Tinley Park, Worth, Palos Hills, Palos Heights, Palos Park, Orland Park, Morton Grove, Golf, Glenview, Deerfield, Libertyville, Grayslake, Riverdale, Dixmoor, Glenview, Northbrook, Calumet Park, Blue Island, Harvey, Markham, Thomton, Lake Villa, Long Lake, Fox Lake, Elmwood Park, River Grove, Franklin Park, Elk Grove Village, Schaumburg, Hanover Park, Streamwood, Hoffman Estates, South Barrington, Barrington Hills, Bensenville, Wood Dale, Itasca, Roselle, Carpentersville, St. Charles, Geneva, Batavia, Montgomery, Oswego, Sauganash, Edgebrook (North), Edgebrook (South), Sauganash Woods / River’s Edge, Ravenswood Manor, Ravenswood Gardens, Norwood Park, Edison Park, Belmont Heights, Garfield Ridge, Clearing, Mount Greenwood, Morgan Park, Hegewisch, Hazel Crest, Homewood, Flossmoor, Olympia Fields, Matteson, Richton Park and more. Zip Code : 60605, 60610, 60611, 60601, 60602, 60603, 60604, 60605, 60606, 60610, 60611, 60654, 60606, 60610, 60611, 60625, 60630, 60640, 60614, 60640, 60660, 60618, 60641, 60618, 60657, 60613, 60614, 60625, 60659, 60613, 60618, 60657, 60625, 60659, 60646, 60630, 60610, 60614, 60625, 60640, 60626, 60618, 60657, 60640, 60660, 60613, 60659, 60645, 60613, 60657, 60639, 60634, 60641, 60707, 60622, 60647, 60630, 60631, 60646, 60647, 60651, 60624, 60647, 60641, 60639, 60641, 60622, 60647, 60614, 60643, 60608, 60615, 60609, 60653, 60620, 60619, 60608, 60636, 60615, 60637, 60653, 60629, 60605, 60607, 60608, 60616, 60649, 60617, 60619, 60637, 60615, 60637, 60609, 60621, 60607, 60606, 60607, 60610, 60612, 60622, 60661, 60608, 60616, 60606, 60622, 60610, 60661, 60607, 60622, 60612, 60607, 60612, 60622, 60647, 60610, 60402, 60130, 60398, 60515, 60201, 60202, 60203, 60035, 60540, 60563, 60564, 60565, 60453, 60454, 60456, 60457, 60458, 60459, 60301, 60302, 60303, 60304, 60305, 60173, 60179, 60192, 60193, 60194, 60195, 60196, 60076, 60077, 60091, 60093