Getting Plastered

Old wall showing hard plaster

Now the frame is up and the electrical and plumbing work has been roughed in its time to do the plastering. In this house there are two types of plastering and two seperate trades doing that plastering. The first type of plastering is dry work using plasterboard that is either fixed to the studwork, to battens or directly stuck to existing walls. Where new studwork occurs the plasterboard is nailed to it in horizontal panels. At the old house metal battens were used where the wall was large, on small areas the plasterboard was ‘direct fixed’.

Plastered

The battens are fixed to the wall with small cleats. The cleats have ‘teeth’ on arms at different that are at different points away from the wall that allow the battens to be placed closer or further from the wall. Minor adjustments are made by bending the arms towards the wall so that the battens can be fixed plumb despite walls being uneven.

Battens

Where plasterboard is direct fixed the existing wall is scrapped back and cleaned at regular points so that blobs of adhesive plaster can be smeared on the wall (at approximately 450mm centres). The board is them pressed into position till it is plumb. This type of fixing was suitable for small bits of wall – not larger areas.

At the base of the new walls P50 stopping beads were fixed to create a 10mm rebate between the walls and the floors. This gives a great effect of lightness and flow (described in the ‘niblessness’ post). At corners metal trims are used to provide a crisp straight edge and to protect the corners. Finally wet plaster was smeared between boards and at the trims to join the plasterwork into a coherent whole. The plaster is then sanded back to give a smooth, continuous surface.

The other plastering was ‘rendering’ or wet plaster work. This is the traditional method of solid plastering over masonry to give a solid plaster finish. We did this in the old building where old plaster was disturbed at opened arches, switches, loose plaster and where skirting had been removed. This involved applying a grey cement, sand mix as a filler (for about 20m) then applying a plaster topcoat as a finish. The effect of this raw plaster looks great – a soft white, handmade look. Unfortunately it was going to be painted to match the rest of the house.

Plaster Batten With Cleat

We also had to plaster over textured walls that had been surfaced to hide imperfections in the walls prior to selling the house. To do this we had to paint the walls with Boncote, a type of glue that creates a strong surface capable of being plastered over. Then a topcoat was applied.

Advertisements

Bad floors

Floorboard

Tasmanian Oak

The existing house has 140mm wide by 28mm thick baltic floors that are old, dirty and not joined properly. Our choice was to either pull them up and redo the floors or try to match them. To redo the floors would have been expensive and, in any case, we preferred the slightly aged look of the existing floor, therefore we decided to match the floorboard. We drove to Urban Salvage in Melbourne and had a look at their recycled floorboards. We chose Tasmanian Oak instead of Baltic because Baltic is too soft for flooring in my opinion. (Hardness is measured on the Janka scale http://en.wikipedia.org/wiki/Janka_hardness_test).

The flooring over the new part of the house sits on battens bolted to the concrete floor. The concrete was sealed with a liquid, roll on, waterproof membrane prior to battens being laid. We asked our builder to lay the floors badly. By this we meant that he should try to match the old floor by leaving varying gaps between the boards. The top photo shows these gaps and a plastic ‘spacer’ that was used to ensure consistent spacing. I think this level of imperfection was hard to swallow for him but that’s the way it has been laid and it looks as if its been there a long time.

Towards the end of the job this floor will be sanded back and given a finish that I’ll write about later. We did sand around the base of the walls because there will be a rebated finish to the plaster that would be impossible to sand later.

Lighting

High ceilings, big windows and good lighting (which can be dimmed) is a recipe that makes it hard to make bad space. High ceilings and big windows are easy to understand but lighting is complicated. Lighting is described in a number of ways: Lumens, colour temperature, colour rendering, angle… All of these have a strong impact on the mood of a space.

Colour temperature is a key mood effect with lighting and describes the colour of the lighting. In nature an ember in a fireplace would have a very low colour temperature and it would appear red – this would often be associated as a cosy type of light, daylight has a very high colour temperature and would be appear white, even blueish – again humans associate this with a freshness and daytime. A ‘warm’ colour temperature would be around 2500K and would be like a 50W incandescent bulb, a ‘cool’ white light might be around 5000K and would be like overcast daylight.

Lumens describes the light level falling on an object and is measured in candela. It is taking over from wattage as a description of a light – eg a 1750 lumen fitting as opposed to a 100W light. This makes sense now that LED’s and other types of light are available. It is also better to describe the light output rather than the energy input.

Colour rendering is the ability of a light to accurately represent the actual colour of an object. In some case a light with be strong enough to light an object but the object may appear weird; reds might not show up accurately while other colours seem fine – this is a problem with colour rendering.

Finally, for the purposes of this post, lights come with different beam angles. The wider the beam angle the less lumens falls on an object. This is true even if the power of the light fitting is the same.

So what type of lights? Well current regulations seek to achieve a power usage level of 5W per meter square or less (in Australia). This means that the lights will predominantly be LED’s. These are very efficient, long lasting lights. On the downside they sometimes contain fairly poisonous material – so getting rid of them is hard. They also don’t change colour temperature as the power changes. Old incandescent and halogen lights went from a very warm colour when dimmed to a bright colour when not dimmed. This is what we expect to happen with lighting and gives a natural effect that is pleasing. When LEDs are dimmed a blueish ‘bright’ light can be dimmed to make a blueish eerie light that is deppressing.

Because I feel dimmable lights are so important I use warm white LED’s of 2700K or less were possible. This allows them to be dimmed without looking too odd. In a couple of places I have used halogen lights so that I get a better quality atmosphere where it matters. These halogen lights occur as wall washers in some areas and as pendant lighting over the dining table. We also plan to use plenty of loose lamps to create variety.

With light layouts it is important to light areas for specific reasons. Sometimes lights are spread evenly over a ceiling to give a general room light level. This approach leads to a fairly dreary quality of space more suitable for an office (if its a dreary office). The lights for this project are specific to tasks or moods we seek to achieve. Two examples are the bathroom and the main living area.

In the bathroom we have halogen wall lights on either side of the mirror on one dimmable circuit and an LED pendant with a red glass surround that hangs over the bath and which would be behind a person facing a mirror on another dimmable circuit. There is also an LED downlight in the centre of the room, again on a dimmable circuit, as general lighting. This means that the pendant can provide soft backlight to anyone looking at a mirror (and remember vanity is insanity) while the mirror lights can give flattering lighting to the face – the centre downlight would be off. If someone is reading in a bath (me) then the pendant has a small opening at the bottom of the glass that allows a beam of uncoloured light out, the rest of the room would be red and fairly dark from the coloured glass.

In the living area we have narrow beam (24deg) 13W LEDs spaced evenly along the wall about 500mm from the wall. These act as wall washers lighting the walls only, these walls are white and will reflect ambient lighting into the room. Four LEDs on adjustable gimbles sit withing two recessed boxes near the centre of the room, they light up the centre of the room and will be adjusted to point at the sofa, two chairs and a coffee table. This room will also need a floor light or lamps on furniture to add variety, scale and nighttime cosiness.Light Layout

Cladding

The house is clad in different materials. At ground level we are cladding the frame with brickwork to creat a brick veneer construction. The idea behind this is to try to draw the old and the new building together. The new brickwork was meant to match the old brickwork i.e. slightly messy but I fear the bricky couldn’t bring himself to be that sloppy. We are partially ‘bagging’ the exterior of the brickwork to help make the old and the new match better. ‘Bagging’ is where cement is rubbed over the brickwork to create a semi rendered effect. In our case this will be a very light application. Here are some bond patterns. Ours is a common bond.

brick wall bonds

Brickwork

At the upper levels we are using a product called Ezylte Panels which are a magnesium oxide board bonded to polystyrene insulation. The board is good for our purposes because it is fairly cheap, lightweight, has a 1.5hr fire rating and has good acoustic and thermal properties. Ezylite come as 10mm boards too and we are using these to provide fireproofing to the steelwork and to create the panelled green elevation described in an earlier post.

Ezylite Cladding

Finally the roof is clad with a 10mm foil sided bubble wrap type insulation material (name escapes me but I’ll add it in a future insulation post) that has an R2.5 insulation rating. This will be used in addition to 140mm thick batts. Over this we are using Lysaght Kliplok 406 metal roofing. This is a very common product that can be laid at 1 degree or 1 in 50. This allows us to maximise internal space and provide a flatish platform to support the solar hot water system and the solar panels.

Roof Sheeting

Clad House

Framing

This is a catch up post since the framing started in early December. The framing is made up of 90mm x 45mm studwork and will support the bricks at ground level (the bricks structurally aren’t required to do anything) and the Ezylite panelling to the upper storeys. All the framing is braced and tied down. The following photos show the framing going up.
Framing
Roof Rafters
The framing is then straightened using lasers and straight edges. Where any framing bows out it is sanded back and where it bows in it is filled with half mm packing strips. The framing sits on top of bitument paper on the slab.

Niblessness

A bit of an aside about niblessness. In ancient egypt they built temples that led from the outside into the building through a variety of ever more sacred and enclosed spaces. This can be seen hereEgyptian Temple Plan

To the left is the entrance and centre right would be the ‘Altar’. The effect of this spacial change would be to bring any visitor into a more and more solemn space. This being achieved in large part by a change in scale and a greater feeling of enclosure. Egyptian Temple Cut-away.

To some degree we want to achieve this spacial change in the house in reverse – more a flow into the garden. This can most clearly be seen moving from the dining room, to the meals area, to the living area and then to the garden. There is a hierarchy of rooms and an ever loosening flow of space.

The dining room is within the original house and was fairly enclosed with an arch to the West wall, a door to the North wall, a smaller arch to the East wall and a closed southern wall with a fireplace. We still want a sense of enclosure but not to this extent. The larger arch is being squared off, the smaller arch is being enlarged and squared off to match the first arch, the door is being removed and two new openings on either side of the fireplace are being created. These openings extend, nibless, to the fireplace and perpendicular walls. We have made these openings nibless to give a greater sense of spacial flow. More niblessness soon. The new dining room will still be enclosed to some extent and will have a sense of intimacy and even secular sacredness.

From here the meals area opens up with large openings to the kitchen and dining room and no obstructions to the sitting room. Importantly the opening to the sitting room has no ceiling bulkhead: The ceiling wraps up at the sitting area to form the study baluster. This forms a dynamic spacial relationship between the dining room and the sitting room.

Finally the siiting room opens up to be a very open space. The height doubles and the Eastern wall is glass. Deliberatly there are no wall nibs to the garden so that the room incorporates the garden better. This sketch shows two rooms, one with nibs and one without.Two rooms The effect is that one room feels more introspective and secure while the other is more flowing and open. One for a claustrophobic person and one for an agriphobic person. We achieved the second kind of space in our last renovation and liked it so we are doing this again. We are further pushing this link to the outside by running the internal wall out to form a garden wall, by having bifolds that pull away from this wall and by keeping the floor finish flush with the window/door sill finish. A finished example, on a more luxurious scale is this house by Marcio Kogan.Marcio Kogan 

Another master of the spacial flow, albeit a couple of centuries ago, was the thoughtful, soulful, Soane. The Soane Museum in London was his house and the following pictures show how well he manipulated the spacial relationship from one room to another, how light sources are incorporated into that relationship and how a range of spacial experiences are created.Soane House Plan

Looking up from crypt

Backlight

Solar Panels Or Not

Solar panelWhether to use solar panels or not was another choice we had to make. It is very difficult making this choice because there are so many variables. The Clean Energy Council of Australia has a very good website that talks about solar panels which is here http://www.cleanenergycouncil.org.au/cec/resourcecentre/Consumer-Info/solarPV-guide .

For us the equation was whether our mortgage plus our electricity bill would be smaller or larger if we chose to use solar panels. If we were to use solar panels, on a house we intended to stay in for a while, then it seemed that it was more efficient to choose a more powerful system over a smaller system.The size of the system is limited in many cases by how many solar panels can be placed on the roof. Using a panel size of 1600mm x 800mm I guestimated that a 4 or 5 kWh system would fit. With this information I went to a website called Solar Choice http://www.solarchoice.net.au/ who are brokers for solar power installers – probably one of many. I entered my location details and what size of system I was looking for and I quickly received quotes from a number of companies giving costs for different sized systems. The quotes were detailed giving warranties, brands and options.

I followed up on the quote of the company that had a competitive quote and that also offered good warranties. I rang them and given the size of our roof we would be able to use a 4kWh system. The quote for this system on this roof was $8105 (with an REC/ solar credit of $2765 – see clean energy council PDF) . I then tried to assess what a 4kW system would achieve.

It is hard to assess what our energy use will be, we know what it was but that was in an old house with electric heating. Trawling the web I get a figure of around 18kW/day as an average use for this size of house with this many people in it but we hope that it will be less because it is a better insulated building, with hydronic heating and LEDs throughout. A typical bill for a year, based on this assumption would be between $1200 and $2000. The saving we would expect to achieve with a 4kW system would be around $1200. This system would therefore cover most of our energy and would reduce the combined cost of our mortgage plus electricity. As a payback option (without using a loan with interest) the panels would take approximately 10yrs to payback assuming set-up costs are included – with a 30yr loan at 6% this increases to about 22years.

These figures are approximate because there are government incentives and changing rates at which you sell electricty – we sell back at a measly 8 cents per KW in Victoria currently. It is also hard to calculate because different power companies sell power at different prices at different times.

So to summarise it does seem to be a clear advantage to incorporate solar panels on our house.