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Crawlspace Spray Foam Insulation

Advanced Insulation Science that outperforms all other types of insulation

Our expert technicians use industry-leading materials to deliver a seamless, air-tight seal in your crawlspace, maximizing energy efficiency and creating a safer and more comfortable living environment for you and your family. Schedule your free estimate today and start experiencing the benefits of exceptional insulation!

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Crawlspaces & Basement Insulation and Remediation

There may not be an area of the home that creates a bigger hazard to the occupants' health than that of a typical crawlspace.

Most homes with crawlspaces are not properly insulated for moisture control and this can pose health concerns for the occupants, especially children.

Lack of properly sealed and insulated crawlspace can allow deadly and odorless gases to affect occupants. It can also become a breeding ground for insects, rodents and mold. In addition, it could cause damage to the foundation and the floor system.

The Stack Effect

The Stack Effect

The Stack Effect Graphic shows where air will infiltrate a home even if you have proper window and door sealing.

Crawlspaces are often damp, humid spaces due to water runoff from rain, irrigation systems or an elevated water table. While the building code requires crawlspace ventilation, this ventilation does virtually nothing to mitigate moisture problems and can actually make moisture problems worse.

Houses operate like chimneys.

If you introduce a hole at the bottom of a chimney, a natural draft ensues as air exits the top of the chimney.

This is called the stack effect.

Attic ventilation is the top of the chimney and crawlspace ventilation is the bottom.

As air is drawn up through your house, moisture, mold spores, odors and soil gases from the crawlspace find their way into the living space.

The Alaska Problem... And Solution

Crawlspace encapsulation involves sealing the underside of the floor with a Closed Cell Polyurethane spray foam application or fiberglass batting and covering the ground using a 6-mil poly taped or sealed with tremco carefully at the seams and adhered to the top or bottom of the concrete foundation wall.

There are a handful of problems with this method when it comes to Alaska. Because winter temps can drop so low, the best method to avoid freezing pipes is to run them in the crawlspace. If the floor underside is insulated, you not only have a colder floor with the insulation line directly below your feet, but you are essentially creating a cold space for your pipes to freeze in.

Our #1 preferred method is to spray foam the crawlspace walls and rim joist instead, fully encapsulating the exterior perimeter of the crawlspace. With this option, it is actually better to leave the floor underside un-insulated! What this does is create a completely conditioned space so there is no chance of pipes freezing, and the floors directly above are much warmer and more comfortable. Typically for crawlspace vents, we create a removable foam plug that stays in at all times unless a pipe bursts and the crawlspace needs dried out. Otherwise, an open vent is the equivalent of an open window when it comes to energy and heat loss.

The ground plastic is a bit of a tricky one. Per code, the seams should be sealed and ran 6" up the stem wall and sealed around the perimeter. One reason for this is radon gas, which Alaska does not have, or in only very small amounts. What can happen with this system is if any water gets into the crawlspace, it will pool on top the plastic and cause mold/mildew issues.

Our preferred method is to seal the edges of the ground plastic with the wall foam, so any water that might enter through the block wall would seep its way behind the foam, under the plastic, and back into the ground. For seams in the field, we find its better long term to actually leave them unsealed, but to do a full 18 overlap so there is good coverage, but water can get back under the plastic into the ground. In cases where the water table is high, it can still be wise to seal them, but its overall better to have a fully operating sump pump in conjunction with the spray foam and plastic.

For homes not on a crawlspace, such as cabins on pilings, there are options as well. Generally speaking, its best practice to install a crawlspace skirting, and insulate and treat it the same way you would a traditional crawlspace. If this isn't an option, we can still spray the floor underside itself. If this has to happen, any piping susceptible to freezing has to be treated carefully. It involves building a chase around the piping, that has warm air access from above and them encapsulating the outside of it with foam. If not done correctly, this can still freeze so lots of folks will add heat tracing around the piping as added insurance.

The Solution

We are very proud of our projects because our specs are superior and our prices even better! We do not pay any enormous franchise or licensing fees to national companies and therefore, we are able to design a system that fits your home and your budget.

Building Science Experts

Nobody understands the science of building better than .

If you want to build a thermally efficient and airtight home, it's not enough just to insulate. You must choose the right insulation and air sealing system for the application, and be sure it's properly installed.

Did you know.. An improperly insulated and sealed home delivers 4500 lbs. of excess greenhouse gases into the air each year? It can also waste 20 percent or more of the energy used to heat and cool the home.

Our Building Science experts understand the principles of heat, air and moisture flow, and how the building envelope interacts with a building's mechanical systems as well as its occupants.

N.A.S.A. applied one-inch of spray-on foam insulation on the Space Shuttle's External Tank that serves to insulate the tank. The closed-cell foam used on the tank was developed to keep the Shuttle's liquid hydrogen fuel at minus 423 degrees Fahrenheit and the liquid oxygen tank at near minus 297 degrees Fahrenheit even as the tank sits under the hot Florida sun while preventing a buildup of ice on the outside of the tank.

Properly insulating and sealing your homes with Spray Foam is a greener alternative.

We can help you in specifying the right insulation system for our local climate. Call or Fill Out Our Contact Form to Get in Touch with our Building Science experts.

TAP to expand the Better Building Performance - Theory vs. Practice section

It is now well established and accepted by most architects and builders that controlling air infiltration is the best and most cost-effective means of reducing wasteful heat loss and providing a comfortable indoor environment.

Most architects tend to design structures that are tight and energy efficient by incorporating the latest in proven, energy saving construction details into their drawings.

Unfortunately, too many buildings still perform poorly. Why is this?

We have found that since there is no performance specification to dictate building construction, there is no guarantee when it comes to building performance. Regardless of the contractor's ability, tight buildings are not created from a list of materials and drawings in the absence of specifications that dictate the building's designed environmental performance.

takes a different approach

To improve building performance, our company focuses on the basic building science principle that air infiltration compromises the effectiveness of the building envelope. Our approach is incremental - areas of infiltration are diagnosed and fixed in order of magnitude. This provides the most thorough and cost-effective solution possible.

has satisfied clients. Our clients have been extremely pleased as they benefit from cost-savings and an immediate improvement in comfort.

We operate two-part urethane injection equipment to superinsulate new and old buildings. Included in this equipment are special nozzles and guns to seal cracks and small openings which effectively stops infiltration that cause poor thermal performance.

There are other urethane contractors who provide typical spray foam services; however, very few go beyond the installation of conventional spray-roofing and spray-wall insulation processes.

Our capabilities, while serving these common markets in some cases, are specially designed to meet the unconventional needs of specialty markets.

By employing standard and custom equipment which processes foam through both spray and injection techniques, we can utilize numerous chemical systems with varying densities, speeds, closed-cell content, fire rating, vapor permeability, and other desirable environmental characteristics.

While there may be other foam contractors who provide spray and injection services, to the best of our knowledge, we are the only company that currently uses "ratio monitoring" equipment in the field for this process. Ratio monitoring enables our technicians to maintain the exact chemical formulation (mix) for the duration of the installation process.

It is impossible to guarantee that the appropriate mix is being maintained without the use of this equipment.



We start with a complimentary, in-home consultation with one of our licensed insulation experts. You will be quoted fair prices - with no hidden fees - and provided with a reasonable installation timeline from start to finish. Our estimates are sent directly to your email inbox, where you can see line-item pricing as well as terms and conditions.

We Keep Our Promises

Trust is the cornerstone of our long-term success. We have served thousands of happy clients and look forward to serving you!



We show up on time, maintain a tidy job site and perform high-quality work.


Keeping you and your family safe is the most important thing we do.


has the best warranties in the business.


Frequently Asked Questions

When can spray foam be installed?

spray foam insulation is professionally installed at the same point in the construction cycle as other types of insulation. That is, it should be installed after the rough plumbing, electrical wiring, and heating and air conditioning ducts have been installed, but before the interior walls are completed in new home construction. In some cases spray foam also can be applied in older homes, to the inside of roofs and under floors after construction has been completed.

How does spray foam work?

A two-part mixture is applied by trained applicators to the inside surface of exterior walls, to the underside of the roof, and beneath floors in basements and crawlspaces. The spray mixture expands rapidly to fill all cracks and voids, completely and permanently adhering to wood, masonry, metal studs and joists.

What types of spray foam products are available?

There are two basic types: closed-cell, rigid spray foam and "soft" or semi-flexible open-cell spray foams. See the article Learning the Difference between 1/2-lb and 2-lb Spray Polyurethane Foam for more information.

Which is better, closed or open cell?

When it comes to insulating your project, choosing the right insulation material is pivotal. Both open cell and closed cell spray foam insulations offer unique benefits depending on the application. While open cell foam may offer cost savings and better sound absorption, closed cell foam provides superior moisture resistance and structural support.

Ultimately, the decision between the two depends on your specific priorities, budget, and what application the foam is being used in.

You can read more about their differences here and our experts can help you navigate these factors and ensure the best choice for an efficiently insulated and durable structure.

How does closed-cell spray foam provide moisture protection, yet still breathe?

Unlike cellulose and fiberglass materials, closed-cell foam is impervious to water absorption and wicking. Yet, like Gortex® fabric, the closed-cell structure allows the passage of water vapor (high energy particles) to allow your home envelope to "breathe".

Liquid water has much larger particles and is unable to pass into or through a closed-cell foam barrier.

What innovative energy saving techniques does spray polyurethane foam allow?


  • You won't need house wrap with our system.
    The air and moisture sealing effects of the spray polyurethane insulation are far superior to what house wraps can do. Don't waste your money on house wrap if you are insulating with spray polyurethane.
  • You can encapsulate your entire exterior house shell with spray polyurethane.
    This reduces energy loss from recessed lights and drop ceilings while minimizing any chance of frozen pipes in colder climates. In effect, this creates conditioned space everywhere including attics, basements, and crawlspaces. When ductwork is run through these areas, it is kept within conditioned space, substantially increasing the energy efficiency of your home.
  • Spray polyurethane insulation will conform to any size or shape cavity.
    Bay windows, oval windows, angled walls, sloped ceilings, or any other unusual framing designs can be well insulated and tightly sealed the same as the uniform spaced stud walls.
How does the polyurethane insulation seal my house?

Our spray polyurethane insulation is sprayed on as a liquid which reacts and expands in place. This expansion action also seals all of the cracks and crevasses in your wall's exterior sheathing. The result is that air can no longer slip in: your house will be less drafty and more comfortable.

Air leakage can also introduce moisture into the wall cavity, resulting in wet insulation and mold and mildew. With the sealing effects of our spray polyurethane insulation, this will not be a concern.

Won't sealing my house lead to indoor air quality problems?

Most house design professionals will advise you to seal the house structure as tight as possible and provide the necessary ventilation through the heating and air conditioning system.

Many systems employ an "air exchanger" which is designed to pre-condition (either warm or cool) the incoming outside air with the outgoing exhaust air.

In this manner, you can build an extremely energy efficient exterior shell using spray polyurethane foam while still providing controlled and energy efficient ventilation.

Is spray polyurethane insulation code approved?

Yes. Building codes provide for the use of spray polyurethane insulation in the Foam Plastic section. This section of the code also describes the use of thermal barriers.

At what point in the construction of my house should spray polyurethane insulation be applied?

Normally spray polyurethane insulation is installed at the same point in the construction cycle as other types of insulation. That is, it should be installed after the rough plumbing, electrical wiring, and heating and air conditioning ducts have been installed.

If you decide to seal the entire exterior house shell with spray polyurethane, spray insulation may need to be applied in some areas before the ductwork is installed.

Can I use spray polyurethane to insulate an existing home?

Yes. A popular retro-fit use for spray foam insulation calls for applying it to your basement / crawlspace walls and rim joist to massively increase your energy savings.

Another area is attics that need upgrades - baffles are installed and foam is sprayed directly to the underside of roofing system, or to knee walls in the attic area that are prone to leaking air. This can replace the conventional blown in insulation used in the ceilings in some scenarios, but not all.

One technology on the market is Injection Foam; injection foam is used to fill existing walls by drilling small holes and injecting the foam from the outside of the structure. After exhaustive research, we have determined the foam type necessary for this isn't up to our standards, so don't offer this service (it is formaldehyde based and offers very poor R-values). We have found the best time to upgrade to spray foam is when the wall cavity will already be exposed during a remodel.

How does spray polyurethane insulation compare with glass fiber batts and blown-in cellulose?

    Air Leakage:

  • Glass fiber batts will not stop air leakage (it might filter out some dirt and dust).
  • Blown-in cellulose will slow down air leakage.
  • Spray polyurethane insulation will fully stop air leakage.
  • R-value:

  • Glass fiber batts have an R-value of about 3.5 (1-inch thickness).
  • Blown-in cellulose has an R-value of about 3 to 4 (1-inch thickness).
  • Spray applied polyurethane insulation has an R-value of 6.5 to 7 (1-inch thickness).
  • Lasting Ability:

  • Glass fiber batts can sag over time.
  • Blown-in cellulose can settle over time.
  • Spray polyurethane insulation completely adheres to wood and sheathing and is rigid; the result is a permanent barrier to heat loss and air entry.
  • Spray polyurethane insulation will add strength and rigidity to your house. Glass fiber batts and blown-in cellulose will not.
Will I save money if I insulate with spray polyurethane insulation?

Yes! The installed cost of spray polyurethane is somewhat higher than traditional fiber batts or blown-in cellulose. However, the higher initial cost is partially offset because you need not ventilate the roof, the HVAC system is downsized and you will save in your heating fuel and electric bills.

Studies suggest that homes insulated with spray polyurethane use 35 to 60 % less energy than homes insulated with conventional insulation. Your savings may be greater or less depending on your life style, appliances, house site, number and size of windows, etc.

Will spray polyurethane insulation lose R-value over time?

When first installed, spray polyurethane foam's R-value is about 10 for a one-inch thickness.

Over time, the R-value drops to between 6.5 and 7.0 (one inch) and stabilizes at that value. The time it takes to reach an R-value of 6.5 to 7.0 depends on a variety of factors, including total foam thickness.

We report a six-month aged R-value. Many industry studies indicate that a one-inch thick sample of foam will stabilize after six months and maintain that approximate R-value for decades.

Can spray polyurethane insulation be applied directly to electrical wiring? What about installed electrical devices like recessed lights?

Spray polyurethane can be applied directly to electrical wiring. Recessed lights or other fixtures may require a certain amount of air circulation around them for cooling purposes.

In these cases, a box can be build around the fixture with gypsum wall board; then spray foam can be sprayed directly to the outside of the box.

Will spray polyurethane insulation deteriorate over time?

Not that we're aware of. We've looked at 20-year old spray foam projects and we have not observed any signs of deterioration. We expect our spray polyurethane insulation system to insulate and seal your home for the life of the house.

How long has spray polyurethane been used to insulate houses?

Spray polyurethane foam was commercially developed in the United States in the mid-1960's. Homes have been insulated with spray foam since that time.

Will spray polyurethane insulation absorb or entrap moisture?

Most moisture problems in houses are due to moisture entry from air leakage. Because spray polyurethane insulation provides such an excellent air barrier, this source of moisture is virtually eliminated.

Other potential sources of moisture can be excluded with proper construction techniques and materials. Unusual building use (such as freezers or swimming pool buildings) may require a vapor retarder.

Does spray polyurethane foam contain formaldehyde?


What equipment do I need to apply spray polyurethane insulation?

Required equipment elements include a plural component proportioner pump with heaters, dual high pressure heated hoses, high pressure mixing and spray gun, and feed pumps and hoses. In addition, an air compressor and electrical generator may be needed.

Can a homeowner apply spray polyurethane insulation?

Not practically. Spray polyurethane application requires complex equipment and a skilled installer.

Will spray polyurethane insulation strengthen my house?

Yes! Our closed cell foam is rigid and structural. Your walls will be more resistant to winds and you'll notice less creaking and shaking when doors are slammed or when the kids are romping about.

How long does it take to install spray polyurethane insulation?

Quite quickly. A typical 2000 sf house can be fully prepped and insulated with spray polyurethane in less than several days. Large houses or houses with complex design features could take longer.




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