Conservation at Croydon


Croydon Public School is a public, co-educational, primary school located in Croydon a suburb of Sydney that required conservation of its original administration building.

Established in February 1884, Croydon is historically important as one of the first schools built after the Public Instruction Act of 1880. The school currently caters for approximately 596 children from kindergarten to Year 6. The motto of the school is “in all things be prepared”.

Croydon Public was founded in February 1884. Due to the school being built in a very prosperous era, Croydon’s original building, built by William Kemp is in the “grand Classic” style and received many favourable comments at the time. Due to the expense of building such schools the Education Department was forced to restrict school building money from 1884, and therefore few of these types of extravagant style of schools were built.

 The original building at Croydon remains in almost original condition without extensive modifications. The school is being re-developed with the addition of new buildings.

Including in this redevelopment is a schedule of Conservation Works. These works were or the repair and conservation of the historical fabric in the context of development of the wider school site.

The administration building clocktower

The Importance of Conservation of Significant Buildings.

Croydon Public School is of state significance as an example of Victorian Italianate style. Can you imagine the many vast and diverse thoughts the students would have expierenced inside its walls? Although modern methods of education demand a different built environment, incorporating historic building aspects into the total context of an educational institution cements the aspirations, failures, successes and achievements with the current school cohort.

The original building of the Croydon Public School needed extensive repair works to bring it to an acceptable working space as the school administration wing. Over time poor quality repairs, general neglect including water and soil drainage problems saw the deterioration of the masonry walls.

Helitec Structural Services use the lastest technologies to reinstate the structural integrity and historical beauty of conservative buildings. Our conservation works are carried out so that the life of a building is extended without any effect on its historical fabric. We use modern materials that restore the structural integrity of a conservation building without leaving any evidence of the remediation works. Once installed the remediation technology is concealed and unseen. We use heritage mortars and masonries to simulate historical building methods.

Helitec Structural Services masonry craftsmen have built a wealth of skills and experience during completion of many successful Historical & Heritage refurbishment projects. We are “Approved Helifix Installers”.

Relaying of conserved bricks

Conservation Philosophy.

  • The following Conservation Philosophy guides all our decisions affecting a heritage fabric. 
  • Helitec Structural Services adhere to stringent guidelines whilst we are engaged on Historical and Heritage building projects.
  • All work should be undertaken in accordance with the principles of Australia ICOMOS, The Burra Charter, 1999. 
  • All work to the historic fabric of the place, where it remains, should involve the least possible physical intervention. 
  • The conservation and long-term maintenance of the building should be based on a respect for the existing building fabric. 
  • Conservation requires a cautious approach of changing as much as necessary but as little as possible. 
  • Traditional techniques and materials are preferred for the conservation of significant fabric. In some circumstances, modern techniques, detailing or materials which offer substantial conservation benefits may be appropriate. 
  • The use of modern materials and techniques must be supported by firm scientific evidence or by a body of experience. 
  • All significant fabric is to be conserved in accordance with relevant NSW Heritage Council guidelines. 
  • Competent direction and supervision should be maintained at all stages of the works from planning through to completion. All conservation work should be implemented by professionals and/or contractors with appropriate conservation experience and knowledge of traditional building skills and materials.
  • Where any significant fabric or spaces are to be disturbed, the advice of the Heritage Consultant is to be sought and implemented prior to any work commencing.

Methodology of Conservative Brickwork.

Helitec Structural Services undertake extensive investigations during conservation works on historical and heritage buildings including, the extent of damaged or missing brickwork, the extent of deteriorated or lost mortar to brickwork joints, the condition of pointing higher up the whole building should be closely inspected, confirmation if areas of rising damp are still active or have been remedied. Also Checking condition of steel lintels over openings that may be embedded in brickwork. 

Helitec’s Brickwork Methodology
  • Ensure any sources of damaging moisture penetration have been rectified, and the affected area dried out, prior to carrying out any repair works. 
  • Any underlying or ongoing causes of damage should be repaired prior to carrying out refinishing works. 
  • Wash down the wall surface to determine amount of staining and to provide a clean surface to commence repairs. 
  • Where redundant flashings are removed, carefully rake out flashing so as to avoid further damage to the wall surface and repoint. 
  • Remove all self-seeded vegetation. Take care when removing these plants from the mortar joints, early mortar is very soft and could easily dislodge the brickwork. Allow to apply an appropriate biocide as part of the cleaning phase of the brickwork. 
  • Any demolished bricks should be salvaged and retained on site for use in any proposed reconstruction or repair works. This is especially important as the older bricks may be of a slightly different size. 
  • Following the identification of damaged or missing brickwork allow to repair or reconstruct using either salvaged or bricks of a similar colour and character, laid in the same bond pattern as the surrounding brickwork. 
  • Depending on the type and extent of damage to an individual brick it may be possible to turn (reverse) the brick. 
  • Any new bricks are to be approved by the Heritage Consultant. Any new or reconstructed brick lintels are to be constructed in the same manner and profile as the existing. Voussoirs are to match in shape, edge profile and mortar joint thickness. Tuckpointing to be repaired. 
  • Repair holes or damage to brickwork caused by the removal of redundant fittings and services with an appropriate mortar, coloured to marry in with the body of the surrounding brickwork. Ensure that the area to be repaired is dust free and has sufficient tooth for the repair material to be sufficiently bedded to avoid later separation. 
  • If lintel repairs are carried out, care is to be taken to protect the tuckpointed gauged bricks. 
Reinforcing and crack stitching in corner.
Diagional crack stitching full wall height
Crack stitching above openings
Helitec’s Mortar Joints Methodology
  • As mortar joints form such a large part of the construction and character of a brickwork wall, repointing is an action which can significantly affect the appearance and condition of an entire wall. Only areas of damaged or missing pointing should be repaired. Mortar joints that appear weathered, however still carry out their protective purpose, should not be replaced. 
  • Carefully rake out affected joints back to a sound substrate, taking care not to damage the brick edges or widen the width of the existing joint; ideally this should be carried out with hand tools. Thoroughly clean out any loose debris and dust to allow good adhesion between the new mortar and the brickwork. 
  • Ensure that the surfaces are damp, not wet, at time of repointing. Where the edges of the bricks have weathered keep the mortar back from the face to avoid feathering the joint. 
  • Protect adjacent face brickwork surfaces from mortar stains. 
  • Deteriorated lime and sand mortar joints should be repaired with mortar that matches the existing in texture, composition and colour. 
  • To colour match, allow to reveal an unexposed and unweathered portion of mortar. Whilst the effect of the new mortar will be brighter than existing, over time it should weather to match the existing areas being cleaned and retained. It is not acceptable to introduce a new mortar colour. 
  • Any cement or later inappropriate pointing (that is, of a harder composition of the surrounding brickwork) should be raked out and replaced with an appropriate mix of lime and sand-based mortar. 
  • Replacement jointing material should be softer than the brickwork it surrounds to enable the egress of moisture. 
  • Ensure sufficient new mortar is applied to provide sufficient bedding for the surrounding brickwork and to avoid creating pockets which may trap water. 
  • New work to joints should match the technique and appearance of the original jointing to the Heritage Consultant’s approval. The jointing profile of new mortar should be struck to match that on the existing pointing adjacent. 
  • Allow to clean the face of the jointing as part of any overall final cleaning program.