How to cut rigid fiberglass sheet?

Fiberglass sheets are sheets made of thin, small diameter superfine glass reinforced with plastic. The sheets have exceptional tensile strength with resistance to corrosion, fire and chemicals, such as organic solvents, bleach, and acids. The most valued aspect of fiberglass sheets is their strength-to-weight ratio, which is due to the fibers carrying the load while the plastic distributes the weight. Fiberglass sheets are available in thicknesses that range from 1.5 mm up to 75 mm.

How to cut rigid fiberglass sheet

Fiberglass sheet is a commonly used insulating material. But for many people, cutting hard fiberglass sheet can be a challenging task. Here are some useful tips to help you cut hard fiberglass sheets efficiently and safely.

Wear protective equipment

First, you need to make sure you’re wearing proper personal protective equipment, including glasses, gloves, and a mask. When cutting hard fiberglass boards, dust and debris are produced, which are harmful to health.

Use the right tools

For smaller cutting tasks, you can choose to use a steel ruler and blade. In the position to be cut, use a steel ruler to secure the fiberglass board and use a sharp blade to cut along the steel ruler. Maintain steady hand movements while cutting, but do not exert too much force to avoid accidental injury during the cutting process. For larger cutting projects, you may need to use a power tool such as a chainsaw or cutter. Make sure you are familiar with the operating instructions and follow all safety measures. When using power tools, you should also ensure that your hands remain stable to avoid accidental injury.

Measure and mark the insulation

Before you start cutting, measure and mark the insulation to ensure that it fits perfectly into the space. Use a tape measure or ruler to measure the length and width of the area where you’ll install the insulation. Then, mark the insulation with a pencil or marker using the measurements as a guide.

Cut from the back

When cutting fiberglass insulation, it’s best to cut from the back or non-faced side. This will prevent the fiberglass fibers from pulling and fraying, which can lead to itchiness and irritation. To cut from the back, flip the insulation over and cut through the backing paper.

Score and snap

To make the cut, score the insulation with your utility knife or insulation knife, using the straightedge as a guide. Once you’ve made the score, snap the insulation along the line. This will ensure a clean and straight cut.

Safety and cleanliness

When cutting hard fiberglass board, ensure that the work area is clean and tidy. Remove discarded debris and dust quickly to ensure safety and cleanliness. After cutting, check whether the incision is smooth and neat, and trim if necessary.