As a result of drilling and silicone injection having been previously used on the above Edwardian brick heritage property, located in the Melbourne suburb of Flemington, the failure of the process is evident in that, rising damp has still occurred despite the previous owner’s intent in trying to fix the issue.
Salt build-up behind the injected silicone is a very common result of injection which could have been avoided.
Despite the effort in trying to stop the moisture, the buildings previous owner was only trying to do what was right. The fact is that silicone injection seldomly works. It is really only for walls over 2 foot thick. It is certainly not for a heritage double brick structure. Discolouration, as seen above, affects both mortars joint and brick alike; hastening deterioration of both.
Visible deterioration of the mortar joint has occurred above the drill lines from chemical dampproofing.
By using a physical barrier instead, this wouldn’t have occurred. Rising damp is a very hard thing to prevent altogether. In all actuality, every masonry structure will encounter some form of moisture transferral from the clay sub-found material. In the case that physical barriers are installed, the decay of mortar and brick is slowed dramatically. By also increasing airflow under the floor, you are also providing a good natural method of easing rising damp.
Contact melbournebrickrepair.com for further details on how to prevent rising damp.
Is your house cracking up? Made it through winter and now you want to get the house airtight and weatherproof? You may need crack injection and/ or brick stitching.
Cracking at mitre corners is very common in masonry. Fix it with brick stitching.
First, the mortar material in between the bricks should be removed. This will provide longer serving results for the repair. Next, the joints are lined with the steel reinforcement. These elements are either galvanised or stainless steel.
The stitches are installed as regularly as required.
With the brick stitches in, next is the final tamp point.
Replacement mortar is reinstated, making the repair complete.
Raised Ribbon Pointing replacing older Brick Tuck Pointing on Ballarat Heritage Facade
When comparing traditional ribbon pointing as opposed to brick tuckpointing there are several differentiating factors.
As you can see from the above photo, the heavy oxide mix used on brick tuckpointing (top courses) can actually cause issues if not installed correctly. Mortar, often used in only one colour, is used to smear over the original bedding mortar which is visable where the red coloured mortar has fallen off. This is due to the smear coat method only being several millimetres thick or possibly too brittle to start with. In the instance above, this is definitely the case.
Another issue is that due to oxides’ cementitious effect on the mortar matrix, the mix can often be quite destructive to the 80-100 year old brick. Mortar, as also evident above, is smeared over the brick arris; partially covering the face. In tension, this can snap corners off and even break bricks clean in half–especially old, soft brick.
The biggest comparison, besides appearance, is that the traditional ribbon technique will protect the brick, whilst at the same time, provide depth and definition to the masonry facade. Standard tuckpoint can last quite a while but as opposed to the deeper ribbon pointing, the facade will age better and can last a lot longer.
Brick Tuckpointing, before and after lime putty ribbon
Although I am a devout traditionalist and prefer to keep the use of portland cements to a minimum, the patching process of mortar repair, when dealing with natural stone buildings, should allow for a strong and durable patch. All patching and pointing shall be installed utilising soaking methods; working with optimal moisture content in both substrate and mortar. This basically means that substrates remain dampened before and after pointing/ patching has occurred.
Bluestone cottage wall with joint removed. The three smaller stones, known as ‘bees feet’, used to fill the line, can be filled with darker mortar
Bluestone Cottage wall with darkened mortar patch
While the colour may look darker now, the patch will dry lighter to match the colour of the surrounding stone. The skill of the original mason from many years ago has been highlighted again by this restoration.
Turning random rubble into a dressed 300mm ashlar wall–Victorian Bluestone Georgian Cottage
Ribbon Pointing on Victorian Bluestone Cottage
Much care is taken in replacing the old mortar. In this case, the mortar removed was from the original construction from over 150 years ago! The lime based mortar has been replicated with the addition of grey cement.
Bluestone Cottage Restoration, Regional Victoria
Re-pointing ribbon pointing for cottage restoration
The following, true to traditional building style, is the back wall to the same building. The more dressed stones were selected and used for the front walls, as pictured above, with the offcuts and more random pieces used to construct the rear half of the house. Replacing and repairing the mortar on this bluestone cottage was long over due with the bottom image showing the difference of new, left, to old, right.
Mortar pointing/ jointing, for brick and stone buildings should be re-pointed every 30-50 years depending on exposure. Of course, a more hastened maintenance schedule, for aesthetic benefit, can be used and may be beneficial.
Always embossed in Georgian design, Bluestone window lintol, quions (and sill) with extended ribbon pointing to accentuate the rebate.
After we knock out the joints, the replacement material will be placed and shaped to create what is known as ribbon pointing. The idea of ribbon pointing is to effectively ‘flatten’ the wall.
the balance that this will create will be surprising and should come up really well. More to come…