CSR Panel Systems manufactures Hebel Autoclaved Aerated Concrete (AAC). The AAC in Hebel products is manufactured from sand, lime and cement to which a gas-forming agent is added. The liberated gas expands the mixture, forming extremely small, finely dispersed air pockets, resulting in lightweight aerated concrete.

CSR Panel Systems has manufactured Hebel products that have won wide acceptance as innovative and environmentally preferable building materials. This is due to their lightweight nature, excellent thermal, fire and acoustic properties and design versatility. These inherent properties of Hebel products help achieve quick and cost efficient construction practices as well as providing for comfortable operating environments inside the buildings all year round.

Build a premium home with Hebel PowerBlock 

Hebel PowerBlocks are large AAC Blocks with a standard face dimension of 600mm x 200mm, laid in much the same way as bricks but using Hebel Adhesive to form a monolithic structure. Typically, external walls use a single skin of 250mm thick blocks while internal, non-loadbearing walls use 100mm thick blocks. Hebel’s tight manufacturing tolerances deliver beautifully flat, true surfaces that are easily rendered and painted.

Walls built with Hebel PowerBlock are strong and durable, providing the security of solid masonry coupled with exceptional thermal and acoustic insulation properties. With over three times the thermal resistance of double brick, Hebel PowerBlocks exceed the Building Code of Australia (BCA) for energy efficiency regulations for zones 1,2, 3 and 5 without the need for additional bulk insulation.

Hebel PowerBlocks are non combustible and can achieve an Fire Resistance Level (FRL) of up to 240/240/240.

For detached houses, this is well above the requirements for building right up to the boundary line and making Hebel an ideal choice for bushfire prone areas.

Compared to traditional double brick construction, Hebel PowerBlock walls can be laid much faster, saving building time and costs. Building with Hebel Blocks may create more internal floor area for the same building dimensions. Hebel Lintels can be used over windows, doors and garage door openings. Hebel also supplies sill blocks for under windows to complement the overall look of your home.

Fig 1.1 Isometric Concept House

Solid and strong: Hebel PowerBlocks are made from Autoclaved Aerated Concrete (AAC), a strong, solid masonry building material with the advantage of being 25% the weight of conventional concrete.

Acoustic Performance: Significantly reduced sound transmission from room-to-room.

Thermal Resistance: Unique thermal properties result in a more stable inside temperature, reducing the energy required to heat and cool your home, thereby reducing energy bills.

Environmentally friendly: 73% less embodied energy and 61% less greenhouse gas emissions than comparative masonry products*.

*Source: LCA Report GECA 2006.

Fire Protection: Non-combustible blocks with frameless construction deliver superior fire resistance. Hebel PowerBlock systems also allow you to build right up to your boundary line.

Pest resistance: Not a food source for termites or vermin and no cavity construction eliminates the chance of harbouring pests.

Design Freedom: Hebel PowerBlock Wall Systems provide absolute freedom to design and build your ultimate dream home – without compromise.

Technical Support: Competent technical support through Hebel distributors.

Energy Efficiency

The unique combination of thermal resistance and thermal mass make building with Hebel a smart choice for meeting Australia’s stringent building regulations.

The thermal performance of a building depends on a number of factors such as orientation and size and aspect of windows. The R-Value of walls and floors can significantly affect the energy-rating outcome of dwellings. A 250mm Hebel PowerBlock has 3 times the R-Value of a cavity brick wall (BCA Vol. 2 Figure 3.12.1.3). The use of Hebel in walls and floors will provide increased thermal performance that can allow more flexibility with other design aspects of a building.

The thermal efficiency of Hebel systems will also reduce the reliance on heating and cooling appliances. The combined effects of running a heater less in winter and fans or air conditioning less in summer can have a big impact on energy costs and the environment.

Single Skin Construction

The AAC masonry constructed from Hebel PowerBlock products is called “Plain Masonry” and the blocks are masonry units referred to as a “Solid Unit”. The type of solid unit is “Autoclaved aerated concrete masonry unit” complying with AS/NZS 4455 – Masonry Units and Segment Pavers.

The larger face dimension and being a single skin, Hebel PowerBlock walls are erected quickly when compared to double brick construction.

Image 2.1: Hebel PowerBlock home

Table 3.1: BCA Energy Efficiency Compliance

*Note: For elevated ground floor slabs an R-Value of 1.9 is required.

Table 3.2: Wall Element R-Value

Table 5.1: Acoustic Performance

Important Note

It is the responsibility of the architectural designer and engineering parties to ensure that the information in the Hebel PowerBlocks Design and Installation Guide is appropriate for the intended application. The recommendations of this guide are formulated along the lines of good building practice, but are not intended to be an exhaustive statement of all relevant data. Hebel accepts no responsibility for or in connection with the quality of the recommendations or their suitability for any purpose when installed.

Scope

The Hebel PowerBlocks Design and Installation Guide has been created to provide information for detached residential buildings. The design information in this guide has been condensed from the Hebel Technical Manual and AS3700 Masonry structures. The design basis is AS3700 Masonry structures, Section 12 Simplified design of masonry for small buildings. The footing and slab design is based on AS2870 Residential slabs and footings – Construction.

Refer to Table 6.1 for Building Geometry Limitations.

Design Parameters

The structural design information in this guide is based on the data and assumptions in Table 6.2, 6.3 and 6.4.

Design Sequence

Fig. 6.1 details Hebel recommendations for how to design a Hebel PowerBlock home.

Fig 6.1: Flow Chart

Table 6.1: Buiding Geometry Limitations

Where the building geometry is outside the above limitations, the designer must refer to the Hebel Technical Manual and AS3700 Sections 1-11.

Table 6.2: Design Parameters

Table 6.3 Design Parameters – Permanent and Imposed Actions

Image 6.1: Hebel PowerBlock home       Image 6.2: Hebel PowerBlock home

Site Classification

Site Classifications are generally carried out for new housing developments, be they part of a subdivision or an individual allotment. The purpose of the site classification is to assess the subsurface conditions and therefore enable determination of the most appropriate foundations / floor slabs (i.e. the classification will generally determine the appropriate dimensions for house footings and / or floor slabs).

Site Classification is carried out in accordance with the Australian Standard AS2870-1996: “Residential Slabs and Footings”.

The available Classes include S (slightly reactive), M (moderately reactive), H (highly reactive), E (extremely reactive), or P (problem site). Classes S, M, H, and E refer generally to sites in which clayey soils will form the founding strata. The classification indicates how reactive the clay subsoil is to changes in moisture content. The reactivity (shrinking and swelling) of the clay can have a significant impact on the footings/slabs of a building slab, which need to be designed to counteract the movements of the clay soils.

Sites classified as Class P generally present difficulties for the proposed construction. The P classification more often than not suggests deep and/or uncontrolled fill, which cannot provide suitable bearing for the house. In these situations, the house is either founded on the stable materials beneath the fill (i.e. deep footings/piers), or the fill is removed and replaced with compacted, controlled fill.

Slab Design

All Hebel PowerBlock homes must have footings and slabs designed to AS 2870 “Full Masonry”. Local engineering advice should always be sought.

Fig 7.1.2: Slab on Ground

Table 7.1.1 Slab on Ground

GENERAL NOTE: This table is to be read in conjuntion with the requirements of AS2870 and AS3600.

NOTES:
1. A 10% increase in the spacing is permitted where the spacing in the other direction is 20% less than specified.

2. Where the number of beams in a particular direction satisfies the requirements of the maximum spacing given above, the spacing between individual beams can be varied provided that the spacing between any two beams does not exceed the spacing given in the above figure by 25%. These allowances for increased beam spacings do not override the maximum spacings between edge beams and first internal beams as required by clause 5.3.9.

3. For two storey timber framed floor or Hebel floor panel construction, the width of the edge beams must be increased by 100mm and the bottom reinforcement must be increased by one bar of the same diameter.

Table 7.1.2 – Strip Footing 

GENERAL NOTE: This table is to be read in conjunction with the requirements of AS2870 and AS3600.

NOTES:
1. For all beams 700mm or deeper, as specified in the table above, internal footings shall be provided at no more than 6m centres, and at re-entrant corners to continue the footings to the opposite external footing.

2. Internal strip footings shall be of the same proportions as the external footing and run from external footing to external footing ‘side slip joints’ consisting of a double layer of polyethylene shall be provided at the sides of the footing only.

3. Provide ventilation to the sub-floor in accordance with the BCA.

Sub-Floors On Elevated Sites

Hebel PowerBlock must not be used at or below ground level. When building a Hebel PowerBlock structure on a sloping site that is not suitable for a concrete slab, a solid core-filled concrete block or brick substructure may be erected on a strip footing to raise the building and floor system to a level that is clear of the ground resulting in a level building platform that allows sufficient airflow under the floor.

The first course of Hebel PowerBlocks must be laid on a DPC to stop rising damp and to act as a bond breaker between the different building elements.

Termite Protection

Hebel PowerBlocks are not a food source for termites. Solid wall construction still requires termite protection. There are many methods to protect your home against a termite invasion and a qualified professional pest control should be consulted to determine the most suitable method for your design.

The Building Code of Australia recognises an exposed slab edge to a depth of 75mm above finished ground level as adequate termite prevention.

For masonry sub-floor construction a continuous ant cap installed between the brick/ concrete block work and the Hebel PowerBlock also satisfies the Building Code of Australia termite protection requirements.

7.2 Hebel PowerBlock Walls

Generally, the minimum recommended wall thickness is:

• 250mm for external walls
• 150mm for internal load-bearing walls.
• 100mm for internal non-load bearing walls.

Hebel suggests considering a wall as having top and bottom lateral restraints only (one-way vertical span) and designing the appropriate wall thickness, so that retrofitting or changing the location of the movement joints will not be detrimental to the lateral load capacity of the wall. In determining the appropriate wall thickness, the designer shall consider a range of factors relating to relevant codes and project specific considerations, these factors may include:

• Movement joint location
• Bracing considerations
• Vertical (compression) loading
• Out of plane wind/earthquake (lateral) loading
• Required fire rating level (FRL).

The particular project loading configurations could result in walls that exceed the above minimum requirements.

Fig 7.2.1 Typical Hebel Ring Beam Detail

Bond Beam (for vaulted roofs)

A bond beam is a continuous beam around the perimeter of a building for the purpose of providing lateral stability and bracing to the walls for vaulted/cathedral roofs, to minimise cracking at openings. As a minimum, bond beams are to be located at the top of the walls for each floor level, or at a maximum vertical spacing of 3m. Bond beams are constructed of reinforced concrete which is poured in situ between two Hebel PowerBlocks. The minimum dimension of the bond beam must be 100mm wide and 200mm high. Bond beam reinforcement should be not less than 2 rows of 12mm deformed bars placed top and bottom in the centre of the beam (overlapped at least 400mm where it joins).

Where bond beams intersect a control joint, it is important to continue the control joint through the beam. The reinforcing bars must pass through the control joint and terminate 400mm past the joint. Where the reinforcing bars are bridging the control joint, the bars that extend for the 400mm should be fitted into conduit sleeves to allow the wall to expand and contract without causing excessive stress on the wall.

Bond beams must be continuous around a built-in corner.

The ring beam at the base is still required. See Fig. 7.2.1.

Fig 7.2.2 Typical Hebel Bond Beam Detail

Compression

The assessment of Hebel PowerBlock wall compression capacity in this Design and Installation Guide is based on the scope of this design guide (see Section 6.0 and Table 6.1). Three top support conditions are applicable:

1) Supporting concrete slab above (see Section 14 and Fig. 14.26)

2) Supporting floor other than concrete slab above (see Section 14 and Fig. 14.28)

3) Face supported framed floor (See Section 14 and Fig. 14.27)

No vertical support of the wall is considered as worst case in the compression capacity assessment. Under that constraint and for wall heights up to 3000mm:

• 250mm load-bearing external PowerBlock walls have adequate compression capacity for all top support conditions.
• 150mm load-bearing internal PowerBlock walls to 3000mm height have adequate compression capacity for the first two top support conditions, but is not suitable for face loaded framed floors. If face loaded timber framed floors are designed both sides of the wall, their spans are within 20% and loading is the same, this can be considered top support condition 2. Otherwise 250mm Hebel PowerBlock wall is required.

Roof loading on top of the wall through the top plate is considered top support condition 2.

Bending

250mm Hebel PowerBlock walls up to 3000mm height have adequate bending capacity without edge support in wind classifications N1 to N3.

Table 7.2.1 provides maximum wall lengths between edge restraints for wind classifications N4 to N6 and C1 to C4. Both ends of these walls must have edge support.

Edge support must be an engaged perpendicular wall (bracing wall) or a built-in 89x89x5 SHS column. The designer must detail the plate connections at the base and top of the SHS column and specify adequate ties to the Hebel PowerBlock work.

Shear

Horizontal forces, such as wind and earthquake loading, applied to a building are to be resisted by bracing walls. Bracing walls are located generally at right angles to the walls subjected to these forces. All bracing components in the building shall be interconnected to adequately transfer the imposed loads to the footings.

Table 7.2.1

Refer to Appendix K in AS3700 for total ultimate racking forces for houses in wind classifications up to N4/C2. Those tables are based on wall height up to 2700mm. For wall height greater than 2700mm up to 3000mm, factor up the loads by 15%. Earthquake categories H1 and H2 are covered by N3/C1 tables and earthquake category H3 is covered by N4/C2 tables.

Table 7.2.2 provides ultimate racking capacities of unreinforced 150mm and 250mm Hebel PowerBlock walls. This table does not include sliding which the designer must also check depending on compression loads on wall in all wind cases and dowel action at base of wall through hold-down rods.

Lintels General

The minimum bearing lengths at the end of all Hebel lintels is 150mm or L/8, whichever is greatest. The bearing PowerBlock must extend past the end of the lintel by min. 100mm.

Hebel Lintels

Hebel lintels are reinforced sections similar to panels. The lintels are used as supports over doorways, windows and other opening.

Lintels shall be installed so that the surface marked ‘THIS SIDE UP’ is uppermost, as the section reinforcement may not be symmetrical. Hebel lintels are not to be cut on-site.

Table 7.2.4 presents the range of standard Hebel lintels and the associated capabilities.

For larger spans, use structural steel lintels as designed by the project structural engineer.

Steel Lintels

Can be used to support PowerBlock work above openings. refer to Tables 7.2.5 and 7.2.6.

Control Joints

During the life cycle of a building, the building and the materials that it is constructed from will move. These movements are due to many factors working together or individually, such as foundation movement (shrinkage and swelling), thermal expansion and contraction, differential movements between materials, climate and soil condition. This movement, unless relieved or accommodated for, will induce stress in the materials, which may be relieved in the form of cracking. To accommodate these movements and relieve any induced stresses, control joints (vertical gaps) shall be installed to minimise cracking in Hebel masonry walls.

Location of Control Joints

Where control joints are required they are best positioned:

• At no more than 6m spacing unless more stringent requirements are specified in accordance with AS2870.1996.
• At intersecting walls and columns.
• At changes of wall height or thickness, or where chases occur.
• To coincide with movement joints in adjacent elements of structure (floor or roof )
• At junctions of dissimilar materials.
• Where architectural or structural features create a ‘weak’ section.

Movement joints are not normally required below DPC level.

Construction of Control Joints

Straight, unbonded vertical joints are the most common type of control joint. Typically, the vertical joint is 10mm wide and filled with an appropriate backing rod and flexible sealant.

Where stability of the design requires continuity across the joint, Hebel control joint ties should be set in every second bed joint.

Movement joints must be continuous through the entire block wall and all surface finishes. When the control joint is aligned with a window or door opening, the joint must be continuous and may need to be offset to deal with the lintel spanning the opening. In such a case a slip joint must be provided under that end of the lintel. Control joints must also be continuous through any bond beams which have been installed in the wall. This can be achieved by breaking the bond beam at this joint during it’s construction. To maintain lateral strength and continuity of the bond beam, the reinforcing rods should bridge the joint with one side of the beam having conduits cast in for the rods to slide while still keeping the wall in plane.

The control joints should be installed as the wall is being constructed as the joint ties must be installed in the centre of the block ensuring the tie is fully bonded with Hebel adhesive.

Service Penetration

To penetrate services through Hebel walls, core out an appropriate sized hole (typically 10mm larger diameter than the service) and run the service through. A flexible sealant should be used to seal the gap around the service, this will also prevent any cracking/movement issues that may occur with the stress imposed on the blocks if the services were placed hard against the Hebel PowerBlock.

For penetrations through fire rated walls, an appropriate fire collar must be used with fire rated sealants. To affix the services to the Hebel walls please refer to the fixing guide in this manual.

Chasing Services Into Hebel

• Services should be run through cavities where possible to avoid unnecessary chasing into Hebel.
• Where chasing is necessary some basic guidelines need to be followed.

- All Hebel products 100mm or less must not be chased
- All chases must comply with the BCA
- The depth of the chase must not exceed 25mm.
- The width of the chase must not exceed 25mm.
- The maximum number of chases allowed is 2 chases per 1 metre length of wall.
- All chases must be backfilled with a material that will adhere to the wall (Hebel Patch or a sand /cement patching mix).
- Chasing can be done with a Hebel Hand Router or a power router fitted with dust extraction.

Table 7.2.2 Unreinforced Wall

Table 7.2.3 Top-Plate & Hold-Down selection Table

Table 7.2.4: Lintel Selection – Hebel Lintel

NOTE: Hebel lintel for 250mm external wall comprises 100mm lintel on outside face and corresponding 150mm lintel on inside face. Top plate to bear across both lintels, min. 25mm bearing on 100mm lintel.

Table 7.2.5: Lintel Selection – Equal Angles

NOTE: For unequal angles, the long leg is vertical.

Table 7.2.6: Lintel Selection – Galintel

7.3 Floor Panel Systems

Hebel Floor Panels are reinforced AAC panels designs as loadbearing components in commercial, industrial and residential construction applications.

A preliminary thickness of the floor panel can be determined from table 7.3.1 in this guide. Contact your local distributor to confirm the selected floor panel thickness is adequate for the design parameters of span, load, deflection, limit and fire resistance level rating.

After the panels are laid, reinforcing bars are placed between the panels in the recess and around the perimeter of the floor to form the ring anchor system in accordance with Hebel specifications.

The joints and ring anchor sections should be lightly pre-wetted, filled with minimum 15 MPa concrete grout, and rodded to ensure complete and level filling of the notch and groove. A mix of CI:S3:A2 (5mm maximum coarse aggregate) with 150mm slump is usually suitable. The grout should completely cover the reinforcing.

The hardness of Hebel Floor Panels is greater than the PowerBlocks. When ring anchors are placed accurately and mortar is poured carefully and screeded properly, the surface is level and smooth.

When Hebel panels are used in external floor areas such as patios or balconies, it is important to use an approved waterproofing membrane.

Hebel Floor Panels provide an excellent, solid, stable base for tile, slate, marble and other hard surface flooring, including bathroom, laundry and other wet area applications.

The smooth flat surface is also perfectly suited to carpet, vinyl, timber boards, parquetry and decorative plywood flooring.

Panels in General

Panels should not be cut on site unless they are ordered as cuttable. It is preferred they are ordered from the factory at the desired length. Where panels have been cut the exposed reinforcing should be with coated with Hebel corrosion protection compound or an approved equivalent.

Hebel panels are supplied ready for use. They can be simply and easily laid into position with only the joints needing to be mortared. Installation is therefore largely dry and generally no formwork or bracing is necessary. The reinforcing in the panels is custom designed for each project.

Panels installed on Hebel PowerBlock work or steel beans can offer a flooring system that can be laid down exceptionally fast. As well as providing the benefits of rapid construction, differential movement between floors and walls is minimised.

Framed Floors

Hebel PowerBlock construction can incorporate floor construction using joists. Typically the joists are installed onto bearing plates which distribute the floor loads evenly into the supporting blocks. Hebel PowerBlocks are easily shaped to infill between the joists. The infill blocks will provide support for the blocks above the floor framing.

Image 7.3.1: Installed Floor Panels

Table 7.3.1: Hebel Structural Floor Panels

With Flexible Coverings / No Walls Above (L/250 deflection)

With Rigid Coverings / Walls Above (L/600 deflection)

NOTES TO FLOOR PANEL TABLES:
• Length is calculated based on the minimum bearing.
• Minimum bearing is panel length /80 but not less than 60mm.
• Maximum clear span is panel length less than 2x minimum bearing.
• (Length) is maximum standard panel length in metres.

7.4 Decks, Verandahs and Pergolas

When attaching a deck, verandah roof or pergola to your Hebel PowerBlock Wall, the building designer / project engineer must calculate and determine the loads that will be imposed on the Hebel PowerBlocks. For conditions equal to or less than those outlined in table 7.4.2, a timber or steel waling plate may be attached to the block wall as shown in Section 14 details 14.34 and 14.35. This must be affixed using the appropriate number and type of fixings as outlined in Tables 7.4.1 and 7.4.2. The fixings must be either Fischer Injection Mortar 10mm x 80mm long or Ramset Injection Mortar 12mm x 160mm long.

Where the loads that will be imposed on the waling plate exceed the table or the structure is to be detached from the Hebel PowerBlock Walls, a detached post and beam structure may be erected adjacent to the Hebel wall which will ultimately transfer the load directly into the foundation. This type of construction must be designed and certified by the project engineer.

Table 7.4.1 Deck/Verandah Floor Walling Plate Connection

Table 7.4.2 Roof Walling Plate Connection

 Note: Walling plate span capacity to be checked by building designer project engineer. 

 Image 7.4.1: Decks, Verandahs and Pergolas

Hebel stocks many of the products and materials required to construct your Hebel home.

Product	Description	Product	Description
	Hebel Thermoblocks50mm – 300mm (25mm increments)		Hebel Adhesive 20 kg bagUsed for gluing the blocks together at vertical and horizontal joints
	Sill blocks600x200x50mm thick or 100mm thick, 30º slope
	PowerFloor Panels 1800mm x 600mm x 75mm		Hebel Mortar 20 kg bagUsed as thick bed mortar base to provide a level base for the first course
	Custom PowerFloor Panels150mm – 250mm x 600mm by up to 6m
	Hebel Lintels To suit openings up to 5m		Hebel HighBuild render 20kg bagUsed as a preparation coat to level surface providing an even true surface
	Stair treads300mm x 175mm x 1m or 1.2m
	Control joint tieUsed at every third course in control joints		Hebel Patch 10kg bagUsed to prepare minor chips or damage to blocks
	Sliding joint tieFixed to RHS/SHS column every second course
			Corrosion Protection PaintTo coat exposed reinforcement during cutting

1. These notes and details are to be read in conjunction with the project’s contract documentation.
2. All materials and workmanship shall be in accordance with this Installation Guide, the current edition of the Hebel Technical Manual and other Hebel documentation.
3. Refer to architectural drawings for all setting out dimensions.
4. Do not scale drawings, use written dimensions.
5. Should any omission, penetration, cutting of panels, discrepancy or fault exist, contact the designer immediately for a decision before proceeding with work.
6. All load-bearing walls, bearing on Hebel floor panels, shall be supported separately in accordance with the project engineer’s design.
7. Hebel accepts no responsibility for the design or selection of supporting walls, lintels, beams, columns or other structural members.
8. Corrosion protection of all structural steelworks shall be specified by the project engineer or architect.
9. The temporary restraint of walls is the responsibility of the builder or installer.
10. PowerBlocks on site should be protected against rain and water saturation. This can best be achieved by leaving the shrink-wrap cap on the top of pallets and covering the top of blockwork if rain threatens. PowerBlocks should not be laid in the rain.

IMPORTANT
12. Ensure engineering tie-down rods are present and located in accordance with the engineer’s documentation.
13. Ensure control joint locations are marked out in accordance with the engineering documentation

Fig 9.1: Wall Construction Diagram

Coatings

Table 9.1 details Hebel recommendations for Coating System options for Low Rise and Detached Residential construction to deliver a durable, monolithic appearance.

Hebel and Dulux Acratex have developed coating systems designed specifically for the Hebel AAC substrate and warrant these systems for 7 years. Performance requirements for alternate system options are provided. In such circumstances, the project specifier must satisfy themselves that systems are engineered and suitable for relevant project requirements.

General purpose, site or pre-bagged sand and cement renders must not be used on Hebel PowerBlock walls, owing to potential variability and unsuitability of formulation for Autoclaved Aerated Concrete (AAC).

Conventional exterior low build paint systems must not be used, as their ability to accommodate normal expansion and contraction in order to maintain a crack free protective layer is not assured.

Refer to “High Performance Coating Systems” brochure on the website, for more information.

Reinforcing Mesh Installation

Fully meshing all rendered Hebel surfaces using alkali-resistant glassfibre mesh is recommended to assist in maintaining render integrity and minimising consequential cracking. The minimum requirement is to mesh at corners of wall openings (doors and windows) to minimise corner cracking. The mesh should be embedded into the wet first pass of Hebel HighBuild.

Linings

Plasterboard can be direct fixed to internal Hebel PowerBlock walls. It is recommended that battens be used behind plasterboard linings on the inside surface of external walls. Fibre Cement sheet linings must be installed on battens.

Table 9.1 Coating systems for Hebel PowerBlock

PowerBlock Laying Procedure

1. First Course

1. Mix Hebel Mortar according to the directions on the bag.
2. Mix Hebel Adhesive according to the directions on the bag.
3. Lay a DPC (damp proof course) slip joint membrane at the base of all external and internal walls to allow for differential movement between the blocks and the slab/ footing. Cut the DPC around tie rods as required. The DPC must be installed on the slab/footing prior to the application of Hebel Mortar. 
4. Lay Hebel Mortar to get first course level and plumb. Accurately position a block and tap into place with a rubber mallet. Ensure that the block is level in all places.
5. All loose particles and dust must be brushed from the base and vertical end surfaces of all first course blocks before bedding in Hebel Mortar and applying Hebel Adhesive.
6. Apply Hebel Adhesive to the perpend of the base blocks using a Hebel notched trowel that matches the block thickness. Ensure full width coverage with 2-3mm final joint thickness.
7. Position the next block vertically adjacent the first block. Place the block down into position and gently tap the block end horizontally with a rubber mallet to fully close the vertical joint.
8. Tap the block vertically into the base mortar and level with the first block.
9. Repeat until the first course is complete.
10. Bore holes in blocks for tie-down rods using a 40-50mm auger bit and place over rods where required. Rod must be central in hole.

2. Second and Subsequent Courses

1. All loose particles and dust must be brushed from the top of the first course before applying Hebel Adhesive.
2. Apply Hebel Adhesive to the horizontal surface using a Hebel notched trowel that matches the block thickness. 
3. Overlap the block joints a minimum of 100mm over joints in the previous course. Normal practice is to overlap by thickness of the intersecting wall.
4. Install wall ties where required, locating centrally accross block thickness and bed into the Hebel Adhesive.
5. Position the first block in the second course and gently tap accurately into place with a rubber mallet. Joints must be 2-3mm thick.
6. Apply Hebel Adhesive to the perpend of the first block. Position the next block vertically adjacent the first block. Place the block down into position and tap the end with the rubber mallet to fully close the perpend joint. Joints must be 2-3mm thick.
7. Tap the top of the block until level with the previous blocks laid.
8. Repeat for subsequent blocks.
9. Excess adhesive should be cleaned off the block face at the end of each course within 1-2 hours.
10. Large holes can be patched using Hebel Patch in accordance with the directions on the bag.
11. Bore holes in blocks for tie-down rods using a 40-50mm auger bit, and place over rods where required. Rod must be central in hole. 
12. Where required construct a bond beam in the top course of loadbearing walls. Minimum dimension is 100mm wide x 200mm high. Use minimum 50mm thick blocks each side to form up bond beam. Reinforcement to be minimum 2x N12 deformed bars. Refer to Floor Panel Note 2 for grout specification. 
13. Where required construct a ring beam in the top course of the non-loadbearing walls. Cut/rout 60mm x 60mm recess and place 1x N12 deformed bar centrally. Refer to Floor Panel Note 2 for grout specification.

3. Finishing

1. Ensure that all perpends are completely filled with Hebel Adhesive.
2. Ensure holes and chips are completely filled with Hebel Patch. Sand back level.
3. Clean off any remaining Hebel Adhesive runs.
4. The blocks can be sanded when dry to ensure a good surface is presented for surface coatings.

4. Base Rendering and Sealants

1. Mix up Hebel HighBuild render in accordance with the instructions on the bag.
2. Apply alkali- resistant glass fibremesh at corners of wall openings (doors and windows) to minimize corner cracking. The mesh should be embedded into the wet first pass of Hebel HighBuild.
3. Hebel HighBuild should be applied with a hark and trowel with minimal thickness of 6mm. General purpose, site or prebagged sand and cement renders must not be used on Hebel Autoclaved Aerated Concrete.
4. Render must be stopped at control joints to allow the joint to open/close and function correctly Hebel PowerBlock Design and Installation Guide 22.
5. All control joints and gaps between blockwork and framing around windows must be caulked with an appropriate flexible sealant.
6. Install backing rods approx 10mm from surface.
7. Apply primer to the surfaces. 
8. Installed sealants to manufacturer’s specifications.

5. Coatings for External Walls

1. Coatings must comprise a high build acrylic texture coat and finish elastomeric paint membrane. 
2. Conventional exterior low build paint must not be used.
3. Allow Hebel HighBuild to fully cure (approx 24 hours depending on weather conditions). 
4. Apply primer to the Hebel HighBuild.
5. Apply texture body coat such as Dulux AcraTex. Ensure texture coat stops at control joints. 
6. Apply finishing sealants in control joints.
7. Apply first finishing paint elastomeric paint membrane.
8. Apply second coat of elastomeric paint membrane as required. 
9. Refer to manfuacturer’s guidline for coating on AAC PowerBlock work and Hebel HighBuild.

6. Internal Linings

1. Plasterboard can be direct fixed to internal Hebel PowerBlock walls. 
2. It is recommended that battens be used behind plasterboard linings on the inside surface of external Hebel PowerBlock walls. 
3. Fibre cement sheet linings can not be direct fixed to Hebel PowerBlocks. Installed fibre cement sheets linings on battens.
4. Hebel HighBuild render may be directly applied to internal block walls as per pervious instructions.

Floor Panel Notes

1. The ring anchor reinforcement shall be a minimum of N12 grade in accordance with AS1302, unless noted otherwise by the project engineer.
2. Hebel Mortar should be used as grout for the ring anchor system. A nominal composition of 1 Cement: 4 Sand (5mm maximum coarse aggregate) can also be used. Minimum compression strength of f’cg= 15MPa at 28 days.
3. Additives to reduce the grout shrinkage shall only be used in accordance with the manufacturer’s instructions.
4. The installer shall support (chair) reinforcement to enable grout to fully surround the reinforcement. Reinforcement shall not be in contact with the panel when grout is placed.
5. Grout shall be rodded to ensure complete filling of notch and groove.
6. The installer shall provide notch and groove at panel joints as per Hebel standard detail 5.3.5 on page 7.60 in the Hebel Technical Manual.
7. Ensure notch is cleared of all loose material and reinforcement cleaned of all foreign material.
8. Lightly pre-wet notch prior to pouring the grout.
9. Panels shall only be cut on-site as indicated on the engineer’s drawings, otherwise contact your distributor or sales representative.
10. Propping of panels may be required to accommodate minor misalignments until 3 days after ring anchor grout is poured.
11. All propping shall be removed from Hebel Floor Panels before any walls are erected over.
12. Traffic on floor panels is to be avoided for a period of 3 days after the ring anchor grout is poured.
13. All panel dimensions are the responsibility of Hebel’s client and are subject to approval by the client before commencing manufacture of panels.

String Line – A string line is required to accurately set out and lay Hebel PowerBlock Walls.

Brick/Block-laying Profiles – used to gauge the block course are being laid level.

Mixing Bucket – a minimum 20 litre bucket is required for mixing Hebel Mortar, Hebel Adhesive and Hebel HighBuild render.

Electric Drill – an electric drill is required to mix the Hebel Mortar, Hebel Adhesive and Hebel HighBuild render. It is also used to drill clearance holes in the blocks so they can be placed over the tied down rods where required.

Stirrer – fitted to the electric drill, the stirrer is used to mix the Hebel Mortar, Hebel Adhesive and Hebel HighBuild render inside the mixing bucket.

Notched Trowel – the notched trowel is used to apply the Hebel Adhesive to the Hebel surfaces. The width of the trowel must match the block thickness to ensure the adhesive is applied with full and even coverage.

Rubber Mallet – a rubber mallet is required to ‘tap’ the Hebel PowerBlocks onto the adhesive and into place.

Spirit Level – required to install the blocks level and plumb.

Hand Saw – a Hebel handsaw can be used to cut Hebel PowerBlocks to length and height.

Powered Bandsaw – a bandsaw is ideal for cutting Hebel PowerBlocks. (perfect when there are many site cuts to be performed).

Hebel Square – a purpose built square is available for use when marking and cutting Hebel PowerBlocks.

Steel, Plastic and Timber Trowels – these trowels may be required for the installation of the Highbuild render and texture coatings.

Sanding Float – used to even out inconsistencies in the Hebel PowerBlock Wall in preparation for render/texture coats.

Hebel Hand Router – may be used to chase services into solid Hebel walls.

Circular Saw – (fitted with a diamond blade) may be used to chase services into solid Hebel walls.

Electric Router – may be used to chase services into solid Hebel walls.

Crane – may be required to lift large Hebel Lintels and Hebel custom floor panels

Lifting Grabs – required for use in conjunction with crane for lifting Hebel lintels and custom floor panels.

Scaffold – Scaffold is required when building block walls. The amount of scaffold depends on the height of the walls.

Sealant Gun – required to fill the control joints in the Hebel PowerBlock Walls.