What kind of foam goes under concrete slab?

The most common types of under slab or concrete insulation include rigid foam insulations, such as expanded polystyrene (EPS), extruded polystyrene (XPS) and radiant insulation, such as Prodex.

Should you put foam under concrete slab?

Putting rigid insulation under the concrete slab is a great way to ensure that your new space will be energy-efficient for as long as it stands! It's required for many new structures to meet code, and it can also protect the concrete from water damage.

What is the best base to use under a concrete slab?

The best sub-base for a concrete slab is gravel. The soil has to be prepped first before the gravel can be laid down; pouring concrete directly onto rock is not considered a best practice. You can use different kinds of gravel for the subbase as long as it is clean and uniform in shape and size.

How thick should foam be under concrete?

Because concrete is solid, heat or air won't escape as easily as other floors. Therefore, when adding insulation, keep it at least two inches thick, depending on the type of insulation you use.

How do you insulate under a concrete slab?

For under-slab applications, the rigid foam insulation typically should be installed over a gravel base, with a poly vapor diffusion retarder between the gravel and insulation. Additional insulation is applied along the edges of the slab, because that is a primary surface for heat loss.

The RIGHT WAY to Insulate Your Concrete Floor

Why is styrofoam used in concrete slab?

Foamex Diamond Pods, a polystyrene waffle pod system, is leading the way in alternative concrete slab filling solutions, providing concrete slab support and increased thermal insulation. Using Foamex Diamond Pods, construction is quicker and more cost effective than traditional concrete slabs.

How do you insulate a concrete floor before pouring?

What is the best fill under concrete?

The top 6 to 12 inches of the backfill under the slab should be filled and compacted with well-graded gravel or crushed material. “Walls are typically backfilled with the removed earth or with a granular, open-graded material,” says Tull.

What can I use for base under concrete?

What Material is Used for a Slab Base? The base in concrete construction is usually a form of crushed stone. Most concrete contractors want a mix of coarse and fine aggregate to create a compactable base that is going to be safe for settlement and drainage.

What is the difference between XPS and EPS foam?

XPS is manufactured in a continuous extrusion process that produces a closed cell form of foam insulation. EPS, on the other hand, is manufactured by expanding spherical beads in a mold and then using heat and pressure to fuse the beads together. Each product has proponents claiming one out performs the other.

What is the best insulation for concrete floors?

EPS is a good choice for insulating a concrete floor because it has a long-term R-value, alongside a consistent level of thermal resistance, and it is produced in easy-to-manage sheets to allow easy installation.

What do you use to insulate a concrete floor?

Another option for insulating your concrete floor are some more flexible materials such as Knauf rock wool insulation slabs or Rockwool insulation slabs, which also offer a level of sound insulation, apart from known as being great and versatile insulators.

What's the best way to insulate a concrete floor?

Can I use expanding foam to lift concrete?

Polyurethane foam is great for leveling concrete. As the foam is injected under the concrete, it moves and expands. As the foam expands it fills any holes, cracks, and crevices beneath the concrete slab. Once voids are filled, the foam begins to lift the sunken concrete.

Can you level concrete with spray foam?

Concrete Leveling Solutions with Spray Foam

Polyurethane foam can level your concrete slabs by providing a supportive, strong layer below your slab. PolyPier is one of the best products for this! PolyPier is a two-part polyurethane product launched by ECP in January of 2018.

What type of rigid foam insulation should I use?

Choose the right type of rigid foam for your needs

Polyisocyanurate: Known as polyiso for short, polyisocyanurate foam has the highest R-value per inch (R-6.5 to R-6.8) of any rigid insulation. This type of rigid foam usually comes with a reflective foil facing on both sides, so it can also serve as a radiant barrier.

Is XPS foam a vapor barrier?

XPS is manufactured in both an unfaced form or with different plastic facings. However, XPS is considered a vapor retarder, not a vapor barrier.

Is rigid foam a vapor barrier?

Rigid foam board, especially foil-faced polyisocyanurate, creates a vapor-impermeable barrier, so the wall would have limited drying potential. Even more permeable types of insulation, such as expanded polystyrene, are vapor barriers when the installation is thick enough.

Can I pour concrete directly on dirt?

Long story short, yes you can pour concrete over dirt.

How deep should I dig for a concrete slab?

Most concrete slabs will sit 1 to 2 inches higher than the dirt and 2 to 3 inches below the surface of the dirt, making the needed depth of the hole 3 to 5 inches.

What mil plastic should be used under concrete?

The most commonly used vapor barrier under concrete slabs is polyethylene (poly) plastic sheeting with a thickness of 10 mil or 15 mil.