How fire resistant is plasterboard?

This blog post will answer the question, “How fire resistant is plasterboard” and cover topics like fire-resistant properties of plasterboard and frequently asked questions related to the topic.

How fire resistant is plasterboard?

Two layers of 12.5mm fire plasterboard used in a partition or ceiling should give up to one hour of fire protection. Two layers of fire-resistant plasterboard on each side of a partition will give up to 2 hours of fire resistance.

What is pink Plasterboard’s fire rating?

The duration of time that fire-rated plasterboard protects against fire before it burns is used to determine its efficacy. Pink plasterboard should not be depended on primarily to prevent the spread of fire, but rather to stop it momentarily since it is not fireproof, just fire-resistant. Other fire-resistant goods, such as A1 non-combustible insulation, should be used in combination with fire-resistant plasterboard to provide extra fire protection.

Two layers of 12.5mm fire plasterboard used in a partition or ceiling should give up to one hour of fire protection. Two layers of fire-resistant plasterboard on each side of a partition will give up to two hours of fire resistance. When determining the amount of fire protection necessary for a structure, you should always consult an architect or other qualified specialist.

What are the different sizes of fire-rated plasterboard?

Plasterboard with a fire rating is available in two thicknesses: 

  • 12.5mm 
  • 15mm. 

Depending on the requirements for your application, any thickness may be utilized; however, a 15mm fire-resistant plasterboard will provide better fire protection than a 12.5mm fire-resistant plasterboard.

The sheets offered at Materials Market are all 2400mm x 1200mm in size, with 2700mm and 3000mm length sheets available upon request. The tapered edge and square edge versions of the 12.5mm are also available, with the tapered border being more popular than the square edge.

What is the color of fire-resistant plasterboard?

The face of the fire-rated plasterboard is pink paper. This is due to the qualities instilled in Gypsum during the production process, as well as the color of the paper strip used to distinguish it from other kinds of plasterboard with differing properties. The color of moisture-resistant plasterboard, for example, is green.

For this reason, fire-rated plasterboard is commonly referred to as “pink plasterboard.” These colors are consistent across various manufacturing businesses, so you’ll always be able to identify the product you’re searching for at a glance.

Is it possible to paint fire-rated plasterboard?

Yes, you may paint straight on the fire plasterboard or plaster it first and then paint it. Intumescent fire-rated paint may be utilized to preserve its fire protection for optimal performance. This will assist to improve the efficacy of the fire resistance and may also be used to give non-fire resistant panels a measure of fire resistance.

What is the best place to use fire-resistant plasterboard?

Using fire-resistant plasterboard makes great sense in several situations. One is the property’s kitchen, namely the walls, floors, and ceilings around the primary cooking equipment. It’s also a good idea to keep it near connection points or anyplace else that might cause an electrical fire. It’s also critical to apply it to structural components like flooring, walls, and supporting beams.

It’s crucial to think about all of the locations where fire-rated plasterboard can be beneficial, particularly in higher-risk regions, so that the project you’re working on can have the highest degree of fire safety as standard.

What is the best way to install fire-resistant plasterboard?

Plasterboard may be fastened to the wall using adhesives or fasteners. Hammering the boards would most certainly compromise their structural integrity, therefore that is not an option. To ensure the strength and longevity of the plasterboard, always hang it with the grain running horizontally.

It’s critical to measure and record the location of the stud wall behind the panels so that the boards may be attached flat and firmly to the building’s structure. Then it’s only a matter of arranging the boards as needed and pushing in the screws that will hold them in place.

How do I select the right plasterboard?

Plasterboard’s appeal is based on its adaptability. There are numerous primary varieties, each with its unique demands, as well as a variety of narrower options within most of the bigger categories. You can’t go wrong with basic wallboard, but knowing what’s available makes sense – the area you’re fitting up could need a different sort of plasterboard down to the ground.

With that in mind, the most prevalent plasterboard kinds are listed below.

  • Wallboard
  • Plasterboard with vapor check/barrier
  • Reduction of sound/acoustic
  • Fireboard
  • The board that is water-resistant
  • Impact board
  • Four-In-One Plasterboard
  • Tapered or untapered

I will now elaborate on the guidance given above.


The most basic sort of plasterboard is wallboard, which is by far the most popular. You’d very surely end up breaking through the wallboard if you tried to break through one of your walls.

When sound levels aren’t a concern, additional structural strength isn’t required, fire resistance isn’t required, and wetness isn’t anticipated, this is what you use. As a result, wallboard is the most cost-effective variety of plasterboard, albeit it may be placed at double thickness if more insulation or fire protection is required in a hurry. In general, one side will be ivory and the other will be brown; the ivory face will generally be plastered.

Plasterboard with vapor check/barrier

Examine the back of the vapor barrier or the vapor barrier’s reverse side. Look for a thin metallic coating on the plasterboard that stops heated vapor from permeating the board. It’s a feature that protects your home against interstitial condensation, a kind of structural dampening that occurs when moist air passes through a wall and condenses into the water behind it.

Interstitial condensation has a slew of nasty side effects, including:

  • Timber frames, and rafters decay and deteriorate, causing structural damage.
  • Respiratory issues as a result of mold growth behind your walls.
  • Moisture seeping into insulating materials causes an increase in sound and/or heat transfer.

A vapor control layer prevents warm wet air from passing through, lowering the chance of such issues. A vapor barrier or vapor check plasterboard is appropriate for any space that is likely to be humid, such as laundry rooms and bathrooms.

Reduction of sound/acoustic

Plasterboard in general insulates, but sound/acoustic reduction plasterboard is specifically developed and made for that purpose. Insulating materials are sometimes sprayed directly to the back of the board, although plasterboard intended to reduce sound transmission often includes a specific core that is far denser than ordinary. The capacity of your plasterboard to absorb sound waves grows as the core becomes denser.

Core materials and sound-deadening panels vary depending on the application, thus acoustic plasterboard designed to keep outside noise from entering your study walls would operate somewhat differently than one designed to keep sound from fleeing a home studio. Before you purchase, do your research. If you’re trying to block out outside noise, it’s a good idea to measure the decibels and locate a solution that matches. There’s no need to spend a lot of money on a sound level meter when there are dozens of applications for your smartphone.


The plasterboard comes with built-in fire resistance. Because gypsum contains a lot of water, panels that catch fire burn slowly, and the thermal energy released is transformed into steam and channeled away from the plasterboard, keeping the opposite side cold until the moisture runs out or the panel is penetrated.

To make a particular core, fire-resistant plasterboard combines gypsum with a variety of additives, including glass fiber, and the backing will be made of fireproof materials. Although no plasterboard can prevent a fire from spreading endlessly or completely, even the thinnest of fire-resistant boards may provide an hour or more of protection, while others can protect for many hours.

The distinctive pink face of fire-resistant plasterboard will help you identify it, and you’ll utilize it in areas where fires are more prone to start and spread, such as the kitchen. Protection levels vary significantly, with more costly fire boards preventing conflagration for many hours. Although most residential structures do not need such protection, business properties often suggest or are legally obliged to have heavy-duty fire boards.

The board that is water resistant

Water-resistant plasterboard should not be confused with vapor barrier/vapor check plasterboard. While the latter stops moisture vapor, the former has water-resistant chemicals in its core to prevent liquid water from penetrating. It’s the sort of plasterboard you’ll use in regions that are excessively moist or humid, such as under your bathroom tiles. The green face of water-resistant plasterboard may be identified, and it is normally left unplastered as plaster absorbs moisture fast.

Impact board

Stronger boards are often required in particular regions of properties. High-traffic areas, such as hallways, must be able to withstand daily knocks and bumps, and substantial core plasterboard is required to do so. Impact board is a term used to describe these types of materials. The additional resilience of the impact plasterboard is suitable for any location that will see a lot of foot traffic or frequent bumps. If a wall is required to support the extra weight, the additional load-bearing capability might be critical.

Facers composed of heavyweight paper or fiberglass matting strengthen a high-density core, and reinforcing fiberglass mesh is occasionally placed in the core to prevent penetration. Impact plasterboard offers simple repairs in addition to better durability since the denser core and harder faces are more resistant to subsequent work.

However, not all impact boards are made alike, since there are many elements to consider:

  • Surface Abrasion: Determines the abrasion depth before piercing the exterior board.
  • Surface Indentation: This test assesses the plasterboard’s resistance to dents caused by tiny, hard objects.
  • Soft-Body Impact: This test determines how well the plasterboard can withstand impact damage from heavy yet soft items.
  • Hard-Body Impact: This test determines how well the plasterboard can withstand impact damage from a huge hard item.

Four-In-One Plasterboard

4-in-1 plasterboard is a recent invention that can withstand impact, fire, water, and vapors, albeit it is uncommon in residential contexts. Although such durability is highly valued in specific building projects, 4-in-1 plasterboard is often reserved for special projects due to its high cost and scarcity.

Tapered or untapered

Most manuals just cover the many types of plasterboards, but there are also several types of plasterboard edges to consider.

  • Untapered Plasterboard: Because the edges are squared, it’s difficult to make a concealed seam without using more plaster.
  • Tapered Plasterboard has a tapered edge. It’s a more popular design that produces seams that are extremely simple to hide.

Frequently Asked Questions(FAQs), “How fire resistant is plasterboard?”

Can you get fireproof plasterboard?

Fireproof plasterboard, often known as fire-resistant plasterboard, is self-explanatory. Both walls and ceilings may be covered with the boards.

Does plaster burn in a fire?

Plaster is non-combustible and cannot be ignited. Despite its limited chemical reactivity, it can operate as an oxidizing agent under severe situations. It decomposes at high temperatures, creating deadly sulfur oxides. To form gypsum, it interacts with moisture in the air or water exothermically but slowly.

Is 12.5 mm plasterboard fire rating?

If the ceiling is plasterboarded, 12.5mm thick boards are needed to provide fire resistance for 30 minutes. You may need to apply another skim layer or more plasterboard to the ceiling.

Is 15mm plasterboard fire rated?

Knauf Fireshield 15mm is plasterboard designed to provide exceptional fire protection when used in partition, ceiling, and lining systems, as well as encasement and shaft wall systems.

Are plaster walls fireproof?

Compared to drywall, plaster is more fire-resistant. While plaster walls are smooth and level, they do have small surface trowel markings, which give a property a charming Old World atmosphere.

Does plaster burn wood?

Is it true that plaster burns in a fire? A flammable wall is one where the plaster is applied to a wood frame wall. Different plaster kinds and thicknesses will give different fire resistance ratings, but a wood stud wall will not be “non-combustible.”


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