Q: What is polyfoam?
- Polyfoam, at its core, is a polyurethane resin. Some of our foam expands (two-component) while some act as a permeation grout (single-component). The two-component resin, as the name suggests, starts off as two separate chemicals and once mixed, expands from 14 to 50 times the liquid state. Single-component permeation resin reacts with ground moisture (natural or introduced) to infiltrate and combine with soil to create a water-impermeable mass.
- Polyurethane itself has been around since the 1930s and is found in multiple areas of your life today. Fast-forward to 1960 and you have the introduction of polyurethane grouting. Its initial application was used for underground utility grouting. In addition to the original task, you can now find polyurethane resins used for stabilizing soil, lifting slabs and sealing leaks.
Q: How strong is foam?
- Currently, polyfoam is being used to support airport runways, major highways, railway beds and commercial structures. If you’ll indulge our inner-nerd for a second, stiff clay and crystalline bedrock have a load-bearing capacity of 4,000 psf and 12,000 psf, respectively. Our lifting foams yield a compressive strength of 100 psi. in a free rise state, or put another way, 14,000 psf. When injected into soil or under concrete, the strength of polyfoam can increase between 39% and 79%, depending on the state of the injected environment.
Q: What is permeation grouting?
- Unlike its brother, expanding foam, permeation grouting has low expansive qualities. This type of polyurethane resin is a single component that permeates, encapsulates and combines with existing soil and turns the treated area into a solid, water-impermeable mass. Permeation grouting is used for stabilizing weak soil and sealing leaks.
Q: Will polyfoam save me money?
- It certainly can. In some instances, we have seen as much as 60% savings versus a “tear out and replace” method. Not only can it be less expensive from a hard cost perspective, but our processes require far less downtime for you. And we all know that time is money.
Q: Will foam lift my driveway?
- Absolutely! Not only will expanding foam lift your concrete, but it will also compact and combine with the soil underneath your concrete to create a solid connection from soil to slab. Currently, expanding resins are used to lift commercial structures and support runways and railway beds. If it’s strong enough for a railcar, it’s strong enough for your driveway.
Q: How much downtime can we expect?
- Minimal downtime! Obviously, downtime will vary from project to project and whether the project is residential or commercial. For an average driveway lift, our completion time is less than one business day. All of our products (expanding and permeating polyurethane) reach 90% of their full cure within 15 minutes! Treated areas are ready for normal traffic by the time our repair rig leaves the site.
Q: How much does polyfoam cost?
- Just like downtime, pricing will be different from project to project. Pricing structure also varies between our expanding foam division and our permeation grouting division.
- Two-Part (Expanding): Priced by the pound
- Single Component (Permeation): Priced by the gallon
- The amount of polyurethane resin required is based on the square footage of the area and soil conditions (voids, compaction, moisture, type).
- On average, a standard driveway repair can cost between $2,000 and $5,000. Keep in mind this is an average; some can be more and some can be less.
- Commercial applications vary, Contact one of our experts here.
Q: Does foam make a mess? Are there any signs of repair?
- Polyfoam does expand at a rapid rate (some of it up to 50 times its liquid state). That said, our professionally trained technicians do a great job of keeping the foam under the ground and not on top. Throughout the repair process, foam will find its way to the top of soil and out from under concrete. This is by design and means it is working. All visible foam will be removed before our technicians leave the site.
- All foam is injected through a 3/8- to 1/2-inch hole, unlike mudjacking that is approximately a 2-inch hole and certainly unlike traditional foundation repair that can have holes big enough for a grown adult to get lost. Once sealed, our holes are difficult to notice unless we point them out.
Q: Is foam waterproof?
- Yes! And in some repair processes, our resins are used to create water-impermeable barriers!
- The majority of the resins we use are hydrophobic, meaning they have properties designed to repel water. As our resins expand, they push water out of the treated area. These resins also do NOT shrink or swell.
- We also offer a hydrophilic resin (a resin that seeks out water,) when necessary.
Q: How long will foam last?
- Until you remove it! Our material is warrantied for 10 years (guaranteed not to shrink or swell), but we can show you projects with polyurethane resins that are 20-30 or more years old. Some chemists have said the life expectancy of polyurethane resins could be 100 years or more.
Q: How does foam lift concrete?
- You may think, “Foam, there’s no way foam can lift concrete!” Au contraire! As foam is injected under a concrete slab, a reaction takes place from the combination of two chemicals (resin and ISO for short). This reaction causes an expansion process. As the slab becomes pressurized from expansion under the concrete, lifting will begin.
- All lifting processes are monitored with multiple devices (dial indicator, zip level) to ensure proper lifting elevation.
Q: How do you stop erosion with polyfoam?
- Erosion is tricky business and is caused by several factors. Erosion can be mitigated with both permeation and expanding resins. First course of action is to determine why the erosion took place. Was it water, decomposition of organic matter, soil slide, etc.? Polyfoam has a repair application for all of the aforementioned erosion factors.
Q: How does polyfoam stop leaks?
- Due to the low viscosity of polyurethane resins, we are able to inject resins anywhere water can go. Depending on the repair, we utilize both hydrophobic and hydrophilic resins, some of which are semi-rigid and some of which have a high elasticity content.
- During a concrete, leak seal repair, polyurethane resins are designed to seek out and seal all cracks (hairline or otherwise) in a structure. Products are designed to create a bond with concrete or with concrete and soil (if present) to lock out water and create an impermeable barrier.
Q: Can polyfoam stop emergency high-flow leaks?
- Absolutely! We have several methods for sealing leaks in pond dams and levees. Polyurethane resins are a suitable repair for leaks in both earthen dams and concrete structures. Due to the low viscosity (liquid “thickness”) of polyurethane resins combined with the injection pressure, we are able to seal off all water pathways, large or small, high-flow or seeping.
- Our leak seal process can be used for high-flow or low-flow leaks.
Q: Can foam fill voids under structures?
- You bet! Void filling is a staple repair for two-part, expanding polyurethane resin. Most of the time, voids are in an inconvenient location. Due to the less invasive injection methods of polyurethane resins and the expansion rates, polyfoam is able to reach areas otherwise unreachable.
- The other beauty of utilizing polyfoam to fill voids is, the expansion pressure of polyfoam is able to compact weak soil around a void, which would be difficult to do with simply backfilling.
- There is no limit to the size void that can be filled with polyfoam.
Q: Is polyfoam a good option for fixing a sea wall?
- Polyfoam is a great option for fixing a seawall! Seawalls come in all different forms, some metal and some concrete. There is a “poly-repair” for all of them. As with any repair, the utilization of polyurethane resins will depend on the severity of the damage or “wear and tear.”
- The beauty of seawall repair utilizing polyurethane resins is in the time and money savings. We don’t require a “tear out and replace,” and our on-site footprint is small and quiet.
- Not all polyurethanes are created equal. Make sure you know the right approach for your seawall.
Q: How do you keep from overlifting concrete with polyfoam?
- All of our lifting processes are monitored in three ways:
- Dial indicator: Monitors pressure and movement every 1/1000th of an inch.
- ZipLevel: Monitors and measures elevation to determine total lifted height.
- Physical observation and trained technicians: lifting jobs require a minimum of two technicians on-site, trained to observe 360 degrees during the entire process. Our technicians are highly trained on when to introduce material and at what rate.
- Polyfoam begins to set up in 15 seconds and is finished expanding within one minute of pumping with a 90% cure time of 15 minutes. This means that once we reach a desired height based on the measuring methods outlined above, we stop pumping and the material does not continue to expand. The lifting process moves relatively slowly, so with proper monitoring methods and a trained technician, overlifting is not a worry.