• A range of lightweight, robust, load bearing units manufactured using Class 1 aggregate for fire resistance.
  • Provides an excellent key for plastering and rendering.
  • Available in solid format.


Suitable for use above and below dpc internally and above dpc externally. Not suitable for beam and block flooring and cannot be used in part walls and are restricted for use in flanking wall Robust Detail types E-WM-2, 4 and 11.


Locally sourced materials under strict environmental and social legislation. 100% of the product can be recycled thus reducing the amount of material that is sent to landfill.

Related literature

The following content references this product:

Standard product features


440 x 215 mm.


BS EN 771–3 and complies with Category 1 masonry units.

Mean unit strength:

3.6 N/mm².

Colour/ Finish:

Natural colour with standard finish.

Thermal conductivity:

  • Internal: 0.29 W/mK.
  • External: 0.32 W/mK.

Reaction to fire:

BS EN 13501-1: A1.


NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-80-50/304 Autoclaved aerated concrete (AAC) blocks

NBS Specification

NBS Buliding logo
This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Aggregate Industries - Masterblock concrete blocks


+44 (0)1285 646900

Product reference

Masterlite Ultra


[100 mm]
[190 mm]
Special order.

Manufacturer details

North End Farm Works,
Ashton Keynes,
Wiltshire, SN6 6QX
Tel +44 (0)1285 646900
Fax +44 (0)1285 646891
NBS Plus