Firestop pillows are

passive fire protection Passive fire protection (PFP) is components or systems of a building or structure that slows or impedes the spread of the effects of fire or smoke without system activation, and usually without movement. Examples of passive systems include floor- ...

items used for

firestop A firestop or fire-stopping is a form of passive fire protection that is used to seal around openings and between joints in a fire-resistance-rated wall or floor assembly. Firestops are designed to maintain the fire-resistance rating of a wall ...

ping holes to achieve

fireproofing Fireproofing is rendering something (Building, structures, materials, etc.) resistant to fire, or incombustible; or material for use in making anything fire-proof. It is a passive fire protection measure. "Fireproof" or "fireproofing" can be u ...

. The various kinds of firestop

pillow A pillow is a support of the body at rest for comfort, therapy, or decoration. Pillows are used in different variations by many species, including humans. Some types of pillows include throw pillows, body pillows, decorative pillows, and man ...

s are intended to slow the spread of fire. They are often used to meet

fire-resistance rating A fire-resistance rating typically means the duration for which a passive fire protection system can withstand a standard fire resistance test. This can be quantified simply as a measure of time, or it may entail other criteria, involving eviden ...

s in conduits that need frequent access.

Description and use

Firestop pillows are used for firestopping holes in wall or floor assemblies, particularly in openings that require frequent access (e.g., cable changes), requiring the removal of the firestopping and resealing after the changes are completed. The products are required to have

s and to be used in accordance with a

certification listing A certification listing is a document used to guide installations of certified products, against which a field installation is compared to make sure that it complies with a regulation (e.g., a building code). Typically, products or items are r ...

Pillow types

There are three types of firestop pillows: * rockwool batts with

intumescent An intumescent substance is one that swells as a result of heat exposure, leading to an increase in volume and decrease in density. Intumescence refers to the process of swelling. Intumescent materials are typically used in passive fire protectio ...

resin inside

plastic Plastics are a wide range of synthetic polymers, synthetic or Semisynthesis, semisynthetic materials composed primarily of Polymer, polymers. Their defining characteristic, Plasticity (physics), plasticity, allows them to be Injection moulding ...

bags *

vermiculite Vermiculite is a hydrous phyllosilicate mineral which undergoes significant expansion when heated. Exfoliation occurs when the mineral is heated sufficiently; commercial furnaces can routinely produce this effect. Vermiculite forms by the weathe ...

with intumescent

graphite Graphite () is a Crystallinity, crystalline allotrope (form) of the element carbon. It consists of many stacked Layered materials, layers of graphene, typically in excess of hundreds of layers. Graphite occurs naturally and is the most stable ...

inside of

fibreglass Fiberglass (American English) or fibreglass ( Commonwealth English) is a common type of fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass c ...

bags * intumescent

foam rubber Foam rubber (also known as cellular rubber, sponge rubber, or expanded rubber) is rubber that has been made with a foaming agent so that its structure is an air-filled matrix. Commercial foam rubber is generally made of synthetic rubber, natural ...

The intumescent

resin A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Commo ...

s in batt-based firestop pillows contains

hydrate In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ...

s, or chemically bound water. On the fire side, the plastic bag burns off exposing the intumescent to the fire, which releases the water in the form of vapour or

steam Steam is water vapor, often mixed with air or an aerosol of liquid water droplets. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Saturated or superheated steam is inv ...

. The steam rises and hits the plastic bag interior on the unexposed side, where it condenses back to water, and runs back down to cool the installation below. Batt-based pillows are held in place by compressing them, allowing

friction Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Types of friction include dry, fluid, lubricated, skin, and internal -- an incomplete list. The study of t ...

to restrain them. The

fabric bag and the graphite are noncombustible. There is also no significant release of chemically bound water. The foam-based pillows intumesce, swelling as a result of heat exposure.

External links

Würth Pillows DIBt Approval
{{Fire protection Passive fire protection Firestops