The Durability of SIPs: How Long Do They Last vs. Others?

SIPs (structural insulated panels) have become greatly popular in modern construction systems for their durability, making them the best choice over other alternatives like ICFs and spray foam. 

But do they last longer than these alternatives?

This article will discuss how SIPs differ from other alternatives like ICFs and spray foams, the potential benefits, and what problems you may face when using them.

So, let’s go into it!

How Long Do SIPs Last?

SIPs panels may last for over 60 years on average.

However, some may last for 90 years if they are not installed in moist areas.

Structural insulated panels can withstand category 4 and 5 hurricanes and most tropical storms, but homeowners must maintain them regularly.

The Average Lifespan of SIPs

Structural insulated panels are largely known to last 60+ years.

Unlike ICFs and spray foams, they don’t degrade since they’re wind and watertight. Their longevity depends upon the material of the insulation foam and whether you install them correctly.

SIPs are construction systems built by sandwiching foam insulation between two boards or oriented strand boards (OSBs).

Since it reduces cold-bridging by removing poorly performing timber within the walls, it helps to increase their lifespan. 

Additionally, structural insulated panels are usually used in hurricane-resistant homes.

That means even if you live in a hurricane-prone area, your panels will last at least several decades with proper maintenance. 

SIPs vs. Other Alternatives 

SIPs panels are generally considered a better option than other panels as they’re more cost-efficient, easier to assemble, and more eco-friendly.

Let’s discuss how they differ from other alternatives, like ICFs and spray foams.

Structural Insulated Panels vs. ICFs 

Although both are widely used in modern commercial building systems to combine structures and insulation, they have considerable differences in durability, design, and cost.

SIPs are made with sandwiched concrete form, while ICFs are made of a foam-insulating material filled with concrete.

ICFs (insulated concrete forms) are complete from all sides, while SIPs are ready to assemble factory-made blocks. 

ICFs are more energy-efficient and fire-resistant because of their Fox blocks.

In addition, thermal bridges in construction and two insulations in their structure make ICFs strong heat insulators, and the foam board and concrete design make them incredibly durable. 

However, the most common issues with insulated concrete forms are the higher cost of specialized labor to manufacture these panels, low rebar reinforcement, and indoor humidity problems.

SIPs will be a better choice if you live in a warmer climate since they generally have higher insulation ratings than insulated concrete forms. 

Most builders won’t recommend ICF structures if you live in cold areas as they transfer heat from the inside, leaving your building even cooler.

That said, you may use both ICFs and structural insulated panels to construct your house quicker and make it more efficient.

For example, you can use ICFs in walls and SIPs as roof panels, and it will let the heat come inside through the panels and go out from insulated concrete form walls, eventually improving ventilation and temperature.  

Structural Insulated Panels vs. Spray Foam 

You’ll probably consider buying a structural insulated panel or spray foam when you want an air barrier for your building. Both are used to seal walls, floor, and ceiling holes to make the building airtight.

However, what’s best for you depends on where you live and your budget. 

Spray foam is easy to use and can help you fill all types of cavities in either new or old buildings, while structural insulated panels will require skilled labor to fix the boxes.

Structural insulated panels are factory-made boxes and fit well, while spray foam may have placement problems which eventually will form air bubbles and rot. 

Additionally, spray foam may shrink over time due to temperature variations and low coverage, but structural insulated panel insulation will last longer and is more energy-efficient.  

Advantages and Disadvantages of SIPs

Despite being energy-efficient, better insulated, and eco-friendly, structural insulated panels have a few downsides, like lower fire resistance and moisture damage.

However, these don’t really affect the panel’s durability if you resolve them soon enough. 

First, let’s weigh the benefits of SIP construction. 

Advantages of SIPs Panels

• On-site construction is possible – since they are ready-to-assemble blocks, it becomes easy to do on-site construction, which saves you time. 
• Airtightness – SIPs offer better control over the air inside your home by creating a thermal envelope, which is excellent for insulation. 
• Unique ventilation – Mechanical Ventilation with Heat Recovery (MVHR) is often used in SIPs to allow fresh air to circulate inside and let the pollutant air leave the building. 
• Reduced construction waste – Structural insulated panels are pre-built and pre-designed blocks that only need correct assembling on the site, which reduces on-sight waste.

Disadvantages of SIPs Panels

Despite the multitude of pros, structural insulated panels have a few drawbacks worth considering. 

These downsides include the following: 

• Low fire resistance – OSB and other construction materials in structural insulated panels have low fire resistance. 
• They may attract pests – like other wood products, these panels may attract pets like termites.
• Proneness to moisture damage – in moist weather conditions, structural insulated panels are more prone to catch water from the air and get damaged. 

Factors Affecting the Durability of SIPs

Now that you know how long SIPs last, what are the factors that affect the material’s durability?

Let’s explore the main factors that determine how long your SIPs can last.

• Core Materials: SIPs typically consist of a core material, such as expanded polystyrene (EPS), extruded polystyrene (XPS), or polyurethane foam, sandwiched between oriented strand board (OSB) or plywood. The durability of SIPs heavily relies on the quality and resilience of these core materials.
• Facing Materials: The facing materials, usually OSB, metal, or fiber cement panels also affect durability. Generally, you can expect SIPs with metal as the facing material to last longer.
• Sealing and Joinery: Proper sealing and joinery techniques are crucial for preventing moisture infiltration. Any gaps or poorly sealed joints can compromise the integrity of SIPs, leading to issues such as mold growth, rot, and reduced structural strength.
• Presence of Vapor Barriers: Incorporating effective vapor barriers within the SIP assembly helps manage moisture levels. A well-designed vapor barrier prevents condensation within the panel, reducing the risk of decay and promoting long-term durability.
• Installation Practices: The durability of SIPs is significantly influenced by the precision and care taken during installation. Improper handling, cutting, or fastening can compromise the structural integrity of the panels, leading to long-term issues.
• Adhesive Quality: The adhesive used in bonding the core material to the facing materials plays a critical role in durability. High-quality adhesives ensure a strong bond, contributing to the overall durability and longevity of SIPs.

Final Thoughts 

Structural insulated panels will last for a long time—as much as six decades.

However, how long SIPs last primarily depends on how well you assemble and take care of them.

You’ll need to provide proper cover to them if you live in cold areas, as it will prevent moisture damage. 

In addition, you’ll also have to inspect them after severe storms and patch up any damage to increase their longevity.