Harry Puttock | Renovations...
RENDERING & BEYOND...
RENDERING & BEYOND...
Harry Puttock: Senior Architectural Manager, Sto NZ
OUTSULATION to Insulate
Sto offer ‘Refurbishment’ systems, a way to breathe new life into older facades, a sustainable choice in ‘reuse-repurpose’ rather than demolish and start again, saving money and resources (reducing the carbon embodiment).
A ‘Superhome’ solution where you make an existing cold, non-Superhome into a high-performance Superhome... with OUTSULATION solutions. It's a new cladding option that will allow the incorporation of insulation to the outside (best place) of the building, so there will be no interior size reduction.
We can repair many situations, cracks and damage, allow Roof apron Stop ends to be retrospectively installed.
There are two situations, the first being where you renovate with an extension addition, and this is best discussed and actioned by your selected designer; you can then discuss with them the best Sto Cladding-Façade options to use – there are many.
We address the second situation here, as this is where you have existing cladding that needs more than just a repaint. We call it ‘Refurbishment’, where you rejuvenate your current walls to a new and more modern look with a wide range of colours.
It is essential to know that the two texture types used to create many finishes vary and, in many cases, are unique as all are hand-applied.
MINERAL TEXTURE:
This is the original for Solid Plaster and is still replicated today on thinner render systems made of sand, cement, lime or acrylic modifiers. They are in a bag and mixed with water. They rely on paint for weatherproofing.
ACRYLIC TEXTURE:
Since the late 1980s, acrylic has replaced many mineral textures for those wanting better performance. It uses 100% Acrylic, is tintable (it comes in white), and is always in a pail, as it is premade. It is also weatherproof, more resilient, and more flexible for some resistance to fracturing. At Sto, we paint it as well.
RENDER:
The term “Render” describes a thinner Plaster compared to the Solid Plaster, which is 15-22mm nominal.
WALL TYPES:
1. EXISTING SOLID-PLASTERED HOUSE
(Maybe documented as ‘Stucco’) Has existed since the 1930s. Common issues are fractures and cracks over time.
2. EXISTING FIBRE CEMENT
With sprayed or trowelled textured (Mineral or Acrylic) finish/coating. Popular from the Mid-1990s to the present. A common issue is cracking at the sheet joints (normally every 1200mm)
3. EXISTING EIFS
(Exterior Insulation & Finishing System)
This uses Polystyrene, which comes in several types and colours. The common is white, the nest is grey, and then blue, green, and yellow. Plastered, tapping on the wall gives a hollow, almost tin-like echo. A fully meshed render system uses textures like the above, and many other styles were selected, including Adobe.
4. EXISTING or NEW BRICK WALLS
If bolstered (rather than smooth) we may grid back the high spots.
5. EXISTING or NEW MASONRY
From precast, in-situ through to concrete blocks.
BEFORE
AFTER
MAINTENANCE:
No matter your exterior they all require maintenance, there is no maintenance free system, just low maintenance. With our coats of the StoColour DRYONIC paint, repaint with regular maintenance can be every 12 years, it may be sooner with harsh environmental conditions.
COSTING:
The Refurbishment/Cost would be at least half the cost of the price to remove and reclad.
OUTsulation Cost, will range on what R value you want, but when considering the cost of removing interior linings to add Insulation and relining. Is Like the Refurbishment cost plus the Insulationsupply and fix.
To assist, we offer free advice, though involving a Superhome Architect will give you a greater range of solutions. Reuse and repurpose is a fantastic way to reduce impact on carbon emissions.
FOR EXISTING SOLID WALL:
(Masonry or Solid Brick), We will mechanically fix insulation (full envelope) directly to the outside using countersunk fixings to avoid thermal loss. We then apply the Sto Render and Finishing System.
FOR EXISTING TIMBER FRAMING:
We move to a Bracket and Rail System to allow outsulation over a rigid air barrier. A cavity and a lightweight sheet (incorporating up to 95% post-consumer recycled glass) weighing in at around 18kg/m2. It equals no additional bracing or stress on the existing building. Great on tight hill sites.
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