Fire ResistanceFyfestone Fire Resistance Picture of a fire escapeFyfestone Fire Resistance Fire Escape symbol

All FYFESTONE Blocks provide excellent protection against the effects of fire.

Fire resistance of a masonry wall is taken to be the time elapsed from the start of the test, to failure of stability, integrity or thermal insulation. (30 minutes–6 hours)

Notional periods of the fire resistance for masonry walls to comply with the building regulations are given in Table 14 of BS 5628: Part 3.

 

Relevant factors affecting the use of masonry units for fire resistance purposes are as follows:

Designation of aggregates

Class 1 aggregates

Include limestone, aircooled blast furnace slag, foamed and expanded slag, crushed brick, wellburnt clinker, expanded clay or shale, sintered pulverised fuel ash and pumice.

 

Class 2 aggregates

Include all gravels and crushed natural stone, except limestone.

Relevant factors affecting the use of Fyfestone units for fire resistance are as follows:

  • The function of the wall (load-bearing/non load-bearing)
  • Wall construction - single leaf / cavity
  • Width of the units
  • Wall finish – plaster/plasterboard etc

 

The fire resistances quoted on the individual Fyfestone product data sheets are based on:

  1. Made with class 1 or class 2 aggregate
  2. Load-bearing or non load-bearing
  3. Single leaf (cavity wall construction in bold font.)
  4. No finish

 

For alternative forms of construction, please contact the Fyfestone technical advisory department on 01285 646800.

 

For panel walls which are to provide fire resistance where edge isolation is necessary, special consideration should be given to the edge details.

 

In walls designed to resist fire, any movement control joints necessary should be fitted with a non-combustible material capable of accepting the anticipated movement and sealed with an appropriate material to give the same fire resistance as the blockwork.

Fire Resistance Properties

For Architectural Masonry, Polished and Standard
(With Class 1 Aggregate as BS 5628 Part 3)

PRODUCT LOAD-BEARING CAVITY WALL LOAD-BEARING SINGLE LEAF WALL NON-LOAD-BEARING CAVITY WALL NON-LOAD-BEARING SINGLE LEAF WALL
65mm Solid 1 Hour 1 Hour 4 Hours 2 Hours
90mm Solid 6 Hour 2 Hours 6 Hour 2 Hours
100mm Solid 6 Hour 6 Hour 6 Hour 2 Hours
140mm Solid 6 Hour 6 Hour 6 Hour 4 Hours
190mm Solid 6 Hour 6 Hour 6 Hour 6 Hour
215mm Solid 6 Hour 2 Hours 6 Hour 6 Hour
140mm Hollow 6 Hour 2 Hours 6 Hour 3 Hours
215mm Hollow 6 Hour 2 Hours 6 Hour 4 Hours
100mm Cellular 6 Hour 2 Hours 6 Hour 2 Hours
140mm Cellular 6 Hour 2 Hours 6 Hour 3 Hours

NOTE: All the above products utilise Class 1 Aggregate.

 

The fire ratings shown can be as consistent for all Fyfestone products with the same thickness as product description, providing the product in question utilises a Class 1 Aggregate (Limestone).

 

For further information on products utilising a Class 2 Aggregate (Granite etc.), please contact the Fyfestone technical advisory department on 01285 646800.