Internal walls: partition walls

H+H aircrete is ideally suited to the construction of both loadbearing and non-loadbearing internal walls.

Using aircrete blockwork creates a stronger, more robust partition. It will be less prone to damage than a studwork wall and will provide a more secure fixing for cabinets, bookcases, TVs etc. There is the added benefit of increased sound insulation too, with the best internal sound insulation being achieved with the use of masonry beams, floors and walls.

While giving many of the benefits of traditional masonry or dense concrete, aicrete is much lighter in weight, meaning that timber joists can support non load bearing internal walls made of the aircrete blocks. The joists must be properly designed and sized to suit the span and loading. Steel or concrete beams, concrete floors or beam and block floors can also support aircrete partitions.

Internal applied finishes

Most types of plaster can be applied to H+H aircrete. The choice of plaster type and application should be made with reference to BS EN13914 “Design, preparation and applications of external rendering and internal plastering” Part 2: Internal Plastering.

Traditional sand cement (dense) plasters should  not be stronger than the backgrounds onto which they are applied and the mixing ratios of various plasters are listed in the H+H brochure Designing and Building with Aircrete.

Prior to applying traditional dense plaster, the surface of the blockwork will need preparation.  Mortar joints should be raked by 15mm to provide a good key. Where the wall is constructed of Thin-Joint blockwork we recommend the application of a PVA bonding coat to improve the bond for plastering. The total thickness of plaster is normally 13mm.

Spray finishes

Proprietary plasters with a total thickness of 3-4mm can be applied directly to blockwork, provided it has been constructed with sufficient accuracy. This method of finishing internal walls is particularly appropriate for Thin-Joint systems because of their inherent accuracy.

Dry Lining

Both standard plasterboard and laminated thermal boards can be fixed by bonding directly to the blockwork using dabs or adhesive. Boards with a layer of bonded insulation should be fixed with a suitable adhesive combined with secondary nailing to ensure that laminated linings remain attached to the blockwork in the event of fire.

Plasterboard can also be fixed using battens: timber or a proprietary metal furring system.

Tiling

Internal ceramic tiling is generally applied to blockwork walls over as render or plaster finish. However, if the walls have been well built, to the standard required for plumb and accuracy for the recommended thickness of bedding material, tiles can be fixed directly to block walls.

Fixings

Fixing into aircrete is easy. Plugs, with screws of nails as appropriate, will provide a very secure and reliable fixing.

As a general rule, fixings should not be closer to the free edge of the block than the depth of embedment, nor should they be over-tightened as this can affect the pull-out strength.

Advice on the most appropriate types of fixing for a given situation and pull-out values for a range of plugged and screwed fixings is available on a technical download or from our Technical Services Department.