It is no secret that undertaking renovations, alterations and additions to a terrace or older period style home in Sydney can present distinctive challenges. Enhancing the timeless allure of Victorian architecture can be successfully achieved through thoughtful construction planning and knowledge surrounding these historical treasures. In this article, we delve into the complexities that we’ve encountered and overcome across numerous projects across the Sydney’s Inner West, Inner City and Eastern Suburbs. Through sharing my experiences, I aim to provide you with valuable insights and equip you with practical construction knowledge necessary to identify the various issues that are all too common with these buildings. I also provide a snapshot of suggested solutions or pathways to deal with these challenges.
I am here to help so if you have any questions or need advice during your design and construction journey for your terrace or period style home in Sydney’s Inner West, East or Inner City suburbs, feel free to contact me on john@homebuildingadvisor.com.au
In the mean time, happy renovating!
WHAT TO LOOK OUT FOR WHEN RENOVATING OLDER HOMES IN SYDNEY’S INNER CITY SUBURBS
Building Settlement and cracked brickwork
In cases where foundations have settled over time, it’s common to observe cracks in the external or internal brickwork or render. Particularly, larger cracks emanating from windows, doors, and corners may signify subsidence in your property’s foundations. Uneven shifting or settling of the ground beneath your home could be the underlying cause. Additionally, poor stormwater control may contribute to the deterioration of footings below, exacerbating foundation issues. To address these concerns effectively, consulting with an expert is essential. They can analyse the nature of the crack and recommend the appropriate repair method. Some strategies for stabilising foundations include underpinning, repointing of brickwork, injection grouting, and helical tie systems, which reinforce the wall to prevent further deterioration of cracks.
Existing floor has deflection (is bouncy) or out of level
In older buildings, internal floor structures may exhibit a bouncy sensation or subtle humps as you walk through. This could stem from various factors such as inadequate timber floor structure, termite damage, or settling of the brick piers or strip footings beneath. One approach to address this issue involves underpinning the affected brick piers or strip footings and jacking up, then installing packers under the existing floor joists, thereby achieving more level floors that have less deflection.
Rising Damp to brickwork
Many period style homes in Sydney’s Inner-city suburbs have brickwork that has been impacted by rising damp. Rising damp occurs in older homes that were built on sandstone or brick foundations without a layer damp proofing membrane. This results to moisture travelling up from the ground through the walls by capillary action. Evidence can appear in the form of flaking, blistering or delaminating paint on a brick wall. In exposed brickwork, you often notice deteriorating mortar being sandy and bricks often being overly weathered compared to brickwork in other areas. It is caused by water and destructive salts entering the wall and having no were to go, and thus deteriorating the wall and mortar from the inside out. Also look out for yellow or darker stains along with evidence of mould the lower section of your walls.
Chemical-based products are available for injection into the mortar lines of walls to establish a damp-proof layer that prevents rising moisture penetration. Additionally, it’s crucial to ensure that stormwater lines are properly connected to pipework systems instead of discharging onto the ground below. Implementing a mechanical ventilation system and installing additional ventilation holes to the exterior are effective methods for promoting airflow within the subfloor, thereby reducing moisture levels.
Termite damage to floor joists
Following on from the point above, termites tends to thrive in dark and damp environments. Signs to watch out for include termite mud tubes and droppings, known as frass, which resemble tiny pellets found at the base of infested timber. It’s essential to verify that the ant caps over piers have been properly installed. Any timber structures severely impacted by termite damage must be replaced. Additionally, it’s advisable to have a specialist termite applicator administer chemical treatment to the subfloor to prevent further damage, regardless of whether termites are still active.
Water leaks from the roof
Signs of water leaks from the roof can appear as yellow discoloration on walls and ceilings below, typically noticeable in the upper segments. In attached terraces, it’s crucial to inspect the flashings between your property and neighbouring buildings. Over time, boundary wall flashings may have degraded, become loose, or shifted out of position, allowing water to seep into your home. This issue may arise particularly where the parapet is higher than the roofline or if there’s a box gutter adjacent to it. Another potential point of failure is around roof penetrations such as brick fireplace chimneys. Having a professional installing new flashings should address the water leaks from above.
Water leaks from the neighbours side ground level
During the design and building process, you will need to ascertain if your neighbours ground level is higher than your internal floor level. This becomes particularly crucial when building up to the boundary, as inadequate construction methods can lead to significant repercussions. Essentially, your internal wall acts as a retaining structure for the earth on your neighbour’s side. The subterranean section of the wall should be adequately waterproofed to prevent moisture ingress into your building. If you are constructing a ground floor slab on your property as part of the extension behind the original home, an effective approach to address this issue is to erect an upturned concrete edge beam at the boundary, positioned higher than the neighbour’s ground level, and waterproof it externally if feasible (positive pressure system). In situations where positive pressure waterproofing isn’t viable, a negative pressure system can be implemented to the internal face of the concrete upturn.
Drummy lime plaster render on walls
In many older buildings across Marrickville, Stanmore, Lewisham, Camperdown, Newtown, Paddington, and Surry Hills, you’ll often find a lime render covering the internal brick walls. Drummy walls, characterized by loose, hollow, or cracked render, are a common issue in these areas. You can identify these problem areas visually or by tapping on the walls. To rectify, the loose sections of lime plaster must be carefully removed, and the bricks should be thoroughly cleaned and prepared. Following this, reinforcing mesh is applied, and the walls are re-rendered. A white set plaster is then used to achieve a smooth, uniform appearance over the rendered surface. Some clients may choose to install plasterboard over the existing render, but this is only feasible if the render is securely attached. In cases where the render is loose, it’s advisable for the builder to scrape away all flaking render before glueing and anchoring new plasterboard directly to the brickwork.
Front patio tessellated tiles have delaminated
Another prevalent issue I have observed in period terraces in Sydney is the collapse of the front patio or the popping of tiles. In buildings predating the 1960s, the front patio often served as a repository for loose rubble remaining from construction projects, which was then compacted with cement to serve as a subgrade for tiling. If your tiles have popped and there are signs of substrate collapse in certain areas, then it is likely that they are not tiled over a concrete slab. To address this, it’s advisable to remove the old foundation and reinstall a solid concrete base on which to tile.
Shared sewer lines that are not picked up by Council or a Building Plan Approval
When extending your attached terrace in Sydney’s Inner West, Inner City and parts of the Eastern suburbs, you are may find a common sewer line that is shared by your neighbours. A Building Plan Approval (BPA) is an online approval system where Sydney Water determines if your home design plan affects any of their assets. Unfortunately, whilst these common sewer lines show up on an old sewer diagram, they are not picked up by Sydney Waters BPA. This means that your approved home design plan may be given the OK by Sydney Water and Council without the necessary investigation regarding the impact your design will actually have on the common sewer. If you are extending your home beyond the original ground level footprint, you will likely impact the “common sewer line” that services the other terrace homes upstream. The common sewer often shows itself as a deteriorating copper, cast iron or clay waste pipe. It is recommended that if you come across this situation and you plan on building over the common sewer, you should consult a licensed plumber to upgrade the portion of sewer to PVC and even consider concrete piering or encasing in order to protect it from new building loads created from your extension.
No boundary walls within the roof space of attached terraces
In order to comply with fire separation regulations, your property needs to have boundary walls with the appropriate Fire Resistance Levels that extend upwards within the roof space. If your property is part of a row of attached terraces, check if there is a fire wall in the roof space. I have come across a number of terraces in Annandale and Paddington that all shared a common roof without the adequate fire separation. In this situation, a fire separation system will need to be constructed in the roof space.
New Boundary Walls and Walls within 900mm of the boundary
New boundary walls and walls within 900mm of the boundary need to comply with a Fire Resistance Level (FRL) of 60/60/60. This means that means that the wall system used needs to pass the 60 minute criteria for Structural Adequacy, Integrity and Insulation respectively before failure. To comply, the FRL system needs to be implemented in a continuous form from the foundation up. This can have a major impact to design for upper walls that are offset from the boundary or walls below. It also impacts the method of construction and the type of materials used.
I am here to help so if you have any questions or are thinking of embarking on a design and construction journey for your terrace or period style home in Sydney’s Inner City suburbs, feel free to contact me on john@homebuildingadvisor.com.au
Thanks for reading and happy home building.
