Spray Foam Insulation VS Fiberglass: How To Choose?

As a polyurethane spray equipment manufacturer, I have found in the process of communicating with customers that many customers do not know how to choose the insulation method. Next, I will analyze the two common insulation methods of polyurethane spray insulation and glass fiber insulation.

What is Spray Foam Insulation ?

Polyurethane spray insulation is an insulation method that uses rigid polyurethane foam with a completely closed-cell structure as raw material . It is widely used in building insulation, pipeline insulation, farm insulation and vehicle insulation.

Advantage of PU Insulation Spray

1. Efficient insulation: Pu spray insulation material has low thermal conductivity and effectively prevents heat transfer.
2. Flexible and convenient installation:  Spray insulation materials can be applied to various special shaped structures and large area buildings.
3. Seamless and efficient insulation: The spray-molded foam insulation layer is seamlessly connected, effectively reducing the thermal bridge effect.
4. Efficient installation: Polyurethane spray insulation material is quickly formed and has high production efficiency.

Disadvantages of polyurethane insulation spray (H3)

1. High price: The price of PU foam material itself is relatively high, and professional spraying foam machine and technology are also required during the construction process . We can tailor suitable polyurethane thermal insulation spray materials and professional spraying equipment for you .
2. High construction technology requirements : PU spray insulation has strict requirements on the spraying technology of the construction personnel. They need to be able to master the spraying technology proficiently and solve various problems encountered during the construction process independently and effectively. We can provide you with operator training services to address this issue.
3. Easy to age: Polyurethane spray insulation materials are easily damaged by ultraviolet rays, affecting their thermal insulation ability and service life.

What is Fiberglass Insulation ?

Fiberglass is a thermal insulation material widely used in various fields, including industry, construction, and automotive . By processing fiberglass into different forms, it can be used to create a variety of highly effective insulation products that provide excellent thermal insulation, heat insulation, and fire protection.

Types of Fiberglass Insulation

Fiberglass felt rolls

It is commonly used for thermal insulation of building walls, roofs, floors, etc. Its advantages are easy installation, flexible laying, strong adaptability, and it is particularly suitable for large-area insulation projects .

fiberglass board

Fiberglass board is a plate-like structure made by pressing glass fibers. It has a certain strength and rigidity and is suitable for wall interlayers, equipment insulation, air duct insulation, etc. It not only has good thermal insulation properties, but also has a certain sound insulation effect.

Fiberglass shell

Fiberglass pipe shells are primarily used for thermal insulation in piping systems, particularly steam pipes, hot and cold water pipes, and other applications where heat loss and condensation must be prevented. Their structural design facilitates pipe wrapping, resulting in efficient construction and significant insulation.

Glass fiber composite materials

Glass fiber is often compounded with other materials (such as aluminum foil, aerogel, silicate, etc.) to make high-performance composite materials, which are widely used in insulation projects of industrial equipment, thermal pipes, and air-conditioning systems.

Advantages of Fiberglass Insulation

• High temperature resistance: The highest heat resistance temperature can reach 700℃.
• Excellent fire resistance: non-flammable, produces no toxic smoke when exposed to high temperatures.
• ‌Sound insulation and heat insulation‌: The internal air cavity structure effectively insulates sound and heat

Disadvantages of Fiberglass Insulation

• ‌Fragility‌: The material is brittle, has poor wear resistance, and is easily broken and exposed. Avoid folding or repeated stretching during use to prevent fiber exposure.
• Installation Risk: Broken fibers may irritate the skin or respiratory tract, so protective equipment must be worn during operation.

Comparing Spray Foam vs. Fiberglass

Spray Foam Insulation Cost VS. Fiberglass ‍

project	Polyurethane spray insulation	Fiberglass insulation
Material cost (yuan/㎡, regular thickness)	Higher, generally US$7-20 /㎡ (depending on thickness and formulation)	Lower, generally 4-8 USD / ㎡
Construction costs	Professional equipment + skilled workers, high cost	Manual laying, low construction cost
Comprehensive cost	The total cost per square meter is about 13-25 US dollars /㎡	The total cost per square meter is about 7-11 US dollars /㎡
Maintenance and replacement frequency	Low, lifespan of more than 20 years, basically no need to replace	High, may sink or change with tide after about 10 years of use, and need repair or replacement
Long-term cost-effectiveness	High, long service life, good energy saving effect, saving operating costs	Moderate, initially cheaper but may increase maintenance or energy costs later

Fiberglass insulation has a low initial investment and is suitable for projects with limited budgets;

polyurethane spraying is relatively high, it has the advantages of long-term energy saving and maintenance-free, so it has a better overall cost-effectiveness.

Installation Ease‍

project	Polyurethane spray insulation	Fiberglass insulation
Construction form	On-site spray molding	Sheet or felt roll laying
construction equipment	Special high-pressure sprayer	Manual laying or mechanical fixing
Construction efficiency	Fast and continuous spraying, suitable for complex structures	Low efficiency, complex parts need to be cut and adjusted
Seam treatment	Seamless, integrated molding	Multiple seams, requiring overlapping or tape treatment
Base surface requirements	Adaptable to irregular surfaces	Requires high flatness

Polyurethane spraying is flexible and adaptable, suitable for special-shaped structures and complex base surfaces;

Fiberglass construction is relatively simple, but it has more requirements on structural shape and construction details.

Differences in Thermal Insulation Performance

project	Polyurethane spray insulation	Fiberglass insulation
Thermal conductivity	0.020–0.025 W/m·K, excellent thermal insulation performance	0.035–0.045 W/m·K, slightly inferior
Closed-cell rate	≥90%, forming a continuous and dense foam layer	It has an open-pore fiber structure and is easy to absorb moisture.
Airtightness	Extremely high, windproof and heat-insulating	Poor, thermal insulation performance decays under wind pressure
Moisture resistance	Good, moisture-proof	Highly hygroscopic, requires additional moisture barrier

Polyurethane has stronger thermal insulation performance, especially excellent in moisture and wind resistance;

Fiberglass performs poorly in thermal insulation and is easily affected by moisture, which reduces its effectiveness.

Durability And Service Life

project	Polyurethane spray insulation	Fiberglass insulation
Service life	Up to 20-30 years or more	10–15 years, prone to compression deformation
Compressive strength	High, can directly bear the load	Low, not suitable for load-bearing layer
stability	Good thermal stability, not easy to age	Easy to sink and deform after long-term use
Corrosion resistance	Good, not susceptible to microbial attack	May become moldy or rot after absorbing moisture

Polyurethane spray insulation material has long life and high strength, suitable for long-term use environment;

Fiberglass is more suitable for situations where structural strength is not a high requirement.

Differences in Applicable Scenarios

project	Polyurethane spray insulation	Fiberglass insulation
Roof insulation	★★★★☆ (Recommended)	★★☆☆☆ (easy to absorb moisture)
Wall sandwich	★★★★☆	★★★☆☆
Special-shaped structure	★★★★★ (perfect fit)	★☆☆☆☆ (Construction is difficult)
Pipe insulation	★★★★☆	★★☆☆☆
Industrial cold storage	★★★★★	★☆☆☆☆ (Not recommended)

Polyurethane has a wider range of applications and is particularly suitable for projects with high requirements for thermal insulation and airtightness, such as cold storage, roofing, and special-shaped structures.

Fiberglass is suitable for conventional walls and projects with limited budgets

Summary

Polyurethane spray insulation : suitable for occasions that require high-efficiency insulation, strong airtightness, moisture resistance and aging resistance. It has high construction efficiency and integrated insulation, but has high requirements for construction equipment and operating procedures.

Fiberglass insulation : Suitable for building insulation needs with limited budget and simple structure. The construction is relatively simple, but the thermal insulation performance and durability are relatively weak.

Pioneer Insulation Spray Foam Project

We have over 30 years of experience in the polyurethane foam industry. We can provide a one-stop solution for your polyurethane insulation spray project. We can provide you with a five-year warranty and can provide you with a long-term and stable supply of polyurethane spray raw materials and polyurethane spray equipment.

Contact us today to learn more about our spray foam insulation equipment and to order our catalog to view our complete offering