Meeting The Specification for 10 N/mm2 Blocks with Celcon Hi-Tene Aircrete Blocks

Sponsored by H + H CelconAug 2 2006

BS 5628: Part 1: 1992 “Code of Practice for the Structural Use of Masonry”, Clause 32.2 defines the design strength of masonry as the characteristic strength multiplied by a capacity reduction factor, b, and divided by the appropriate partial safety factor for material, γ_m.

The capacity reduction factor, b, allows for the effects of slenderness of the wall and eccentricity of loads and is not related to the type of masonry units being used. The wall strength is therefore related to the ratio:-

Celcon Hi-Ten^e blocks have a specified compressive strength of 8.4 N/mm² and are manufactured to the ‘Special’ category of manufacturing control as defined in BS 5628: Part 1 Clause 27.2.1.2. This means that the lower value for γ_m given in Table 4 of the code may be used for design purposes. The following table shows how the strength of a wall built with Celcon Hi-Ten^e blocks is equivalent to that built using 10N/mm² solid blocks for which only ‘Normal’ category can be taken.

Typical block thickness	Celcon Hi-Ten^e (γ_m =3.1)		10N/mm² Solid block (γ_m = 3.5)
Typical block thickness	f_k (BS5628: pt1:Table 2 mortar designation (iii)	f_k / γ_m	f_k (BS5628: pt1:Table 2 mortar designation (iii)	f_k/ γ_m
100mm	7.2N/mm²	2.3N/mm²	8.2N/mm²	2.3N/mm²
150mm	5.8N/mm²	1.9N/mm²	6.5N/mm²	1.9N/mm²
200mm	4.9N/mm²	1.6N/mm²	5.5N/mm²	1.6N/mm²

This information has been sourced, reviewed and adapted from materials provided by H + H Celcon.

For more information on this source, please visit H + H Celcon.

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APA
H + H Celcon. (2019, April 23). Meeting The Specification for 10 N/mm2 Blocks with Celcon Hi-Tene Aircrete Blocks. AZoBuild. Retrieved on July 18, 2025 from https://www.azobuild.com/article.aspx?ArticleID=7866.
MLA
H + H Celcon. "Meeting The Specification for 10 N/mm2 Blocks with Celcon Hi-Tene Aircrete Blocks". AZoBuild. 18 July 2025. <https://www.azobuild.com/article.aspx?ArticleID=7866>.
Chicago
H + H Celcon. "Meeting The Specification for 10 N/mm2 Blocks with Celcon Hi-Tene Aircrete Blocks". AZoBuild. https://www.azobuild.com/article.aspx?ArticleID=7866. (accessed July 18, 2025).
Harvard
H + H Celcon. 2019. Meeting The Specification for 10 N/mm2 Blocks with Celcon Hi-Tene Aircrete Blocks. AZoBuild, viewed 18 July 2025, https://www.azobuild.com/article.aspx?ArticleID=7866.