Tag Archives: Affordable

The Role of Ceiling Fans & Exhaust Fans

 

ceiling fans

Ventilation is the active process of “changing” or replacing air to regulate temperature and moisture. It should always occur under controlled conditions, by opening windows or with ceiling or exhaust fans, NOT through gaps and air-leakage.

Exhaust fans

Exhaust fans should always be self-closing, so that the replacement of air is controlled and not accidental. With out a self closing mechanism they are one of the main contributor of air leakage.

However, if they are self-closing they are an effective way to replace air, especially in rooms where no natural ventilation is available, or where natural ventilation might not be sufficient, such as kitchens or bathrooms.

Ceiling fans
Ceiling fans are an easy and cost effective way to improve the indoor air quality in summer and also to gain points towards the desired energy rating stars.

Ceiling fans provide additional air movement/wind, increasing the Relative Air Velocity (‘wind chill factor’) resulting in the apparent temperature felt on exposed skin to be 3 °C colder than the actual air temperature, thereby reducing the need for additional cooling.

Nowadays there are so many efficient fans available on the market.
If choosing a ceiling fan make sure you get one with at least 3 speeds, with the lowest speed being slow enough to still move air, but not to create a cool feeling draught, so that you can use them in winter mode)

 

Thermal Mass: material and colour selection

Material and colour selection

FullSizeRender-3
Generally speaking, the more thermal mass the better and the heavier a material, the better its ability to store heat. The optimum would be a masonry home with a reverse brick veneer construction and concrete floors. Or using something like concrete block walls and insulate at the outside, with isolation boards.

If this option is too expensive use as much thermal mass as possible, concrete slab is preferable. In warmer climates the ground is colder and can help to cool the concrete. Therefore the indoor air temperature will be reduced. In colder climates, however, the concrete slab needs to be insulated from the ground in order to minimise heat loss in winter.  When looking a the energy start rating,  insulating the slab on ground can add up to 1 star to your star rating.

If a timber subfloor is requested or required, the focus should be at least on internal brick walls to the north which need to be exposed to the winter sun and are therefore able to absorb and release heat. Other materials that have a good thermal conductivity are water, sandstone, rammed earth and earth blocks, mud brick etc.

Moreover, colours and coverings can influence the performance of thermal mass. For example carpets and timber floors will minimise the ability of thermal mass to absorb and release heat as they work as additional insulation. This can lower the required heating in winter, but it will increase the need of additional cooling in summer, as the thermal mass can absorb less heat. On the other hand, hard floor finishes such as tiles, stone or slate on concrete slab can increase the ability to store heat. Dark colours or dark materials also tend to absorb more heat, however, light-coloured walls are more desirable as they maximise natural daylight. Dark walls will increase the need of artificial lighting, as they absorb light and can make rooms appear smaller. In short, material and colour selection can promote or adversely affect the performance of thermal mass.

One alternative to adding thermal mass as a actual building material is to add something that acts as thermal mass, but is light weight. There is one product on the Australian market, calle BioPCM. This phase change material acts as thermal mass, without the weight actual thermal mass has, and hence standard light weight construction and footings are sufficient, which are usually significantly cheaper than if you are building with brick and or block work.

“BioPCM™ is a lightweight smart thermal mass, providing design flexibility and easy installation for a cost effective and simple approach to integrating sustainable technology into buildings.
BioPCM™ absorbs excess heat during the day and releases this energy back in the evening as buildings cool.”

 

We have used the BioPCM to line the walls of a pantry, to keep it cooler and create some sort of cool – room. And the result was really great. The room always stays much colder then the rest of the well insulated weatherboard home.

 

 

Winter heat loss through Windows

Winter heat loss

Screen Shot 2016-03-31 at 8.23.38 pm
Unprotected glazing and single glazing in particular means the surface of the glass is noticeable colder than the warm air in the room. This lowers the room temperature and produces draughts. The Relative Air Velocity ends up too high and occupants will feel winter discomfort. For this reason, all windows require protection from heat loss in winter. To minimise winter heat loss, it is important to trap a layer of insulation still air between the window and the room. This can be achieved for instance by using internal coverings, such as drapes, Holland blinds, Roman blinds or Australian blinds, and thin or lace curtains combined with pelmets.

 Effect of window treatments on winter heat loss
(According to Sustainable Energy Authority Victoria 2002)

  • Unprotected single glazing: 100%
  • Vertical or venetian blinds: 100%
  • Unlined drapes or Holland blinds, no pelmet: 92%
  • Heavy, lined drapes, no pelmet: 87%
  • Unlined drapes or Holland blinds, pelmet: 79%
  • Standard double glazing: 67% (the higher the U-value the less the heat loss can be)
  • Heavy, lined drapes, pelmet: 63%
  • Double glazing with Low-E coating: 57%
  • Double glazing, heavy drapes, pelmet: 46%

Double glazing
The most effective way to protect windows against heat loss in winter is a combination of double glazing and internal window coverings. However, if internal coverings are inappropriate or not desired, for instance in highlight or clerestory windows, in kitchens or simply where unobstructed views are wanted, double glazing is an indispensable measurement in order to prevent heat loss in winter. Yet double glazing won’t prevent sun coming into the building, which means that the windows need to be protected from harsh summer sun by means of external shading.

Window frames
Another, often underestimated roll in the energy efficiency of a window, is the frame itself, as it can effect negatively on the overall performance. As we talked about in the blog “Adequate Insulation”, some materials, such as metal, glass or aluminium, allow heat to pass through them more easily, therefore they shouldn’t be used for windows frames if at all possible. If metal frames are used, such as aluminium, they should have thermal breaks to reduce the heat transfer. Generally speaking, PVC and timber frames perform better than metal frames.

 

Summer heat gain through Windows

heat transfer

It is important to protect windows with external shading devices, through appropriate window sizing and location, in order to minimise heat gain in summer.

Comparison of heat gains through different treatments for windows in summer

(According to Sustainable Energy Authority Victoria 2002)

  • Unshaded single-glazed window: 100%
  • Standard double glazing as available in Australia: 90%
  • Vertical blinds/open weave drapes: 76%
  • Internal venetian blinds: 55-85% (Effectiveness is reduced as the colour darkens)
  • Internal drapes or Holland blinds: 55-65%
  • Tinted glass: 46-65%
  • Solar control film/reflective glass: 20-60% (Available in different kind of configuration with varying effectiveness)
  • Trees, full shade: 20-60%
  • 1 metre eave over north wall: 30%
  • Roller shutters: 30%
  • External awnings: 25-30%
  • 2m pergola over north wall covered with deciduous vines or shade cloth: 20%
  • Outside metal blind or miniature louvers, parallel and close to window: 15-20%

External shading devices are an effective way to minimise heat gain through glass in summer and keep a building cool. They provide far better protection from heat gain than internal window covering. However, if external shading is not possible, internal coverings can at least reduce the unwanted heat gains. Shading devices should always enable ventilation outside the window, as shading fitted too closely to a window can trap warm air which can be conducted into the house.

Eaves, verandas or pergolas are commonly a part of the building structure, they are durable and do not require ongoing adjustments. It is essential to have a certain distance between the underside of the shading devise and the top of the window. But these fixed shading devises should only be used over north-facing windows, as they lack flexibility and aren’t adjustable. East and west-facing windows need a flexible shading devise that can be completely retracted in order to let the valuable sun through in winter, but to protect from the harsh summer sun. Adjustable shading includes amongst other things canvas blinds, different types of shutters, angled metal slats, louvers or shadecloth over pergolas. Adjustable shading requires action from the occupants, as they have to respond to climatic conditions.

Apartment Renovation St Kilda – update

No matter how small or large a project, you have always to expect the unexpected. And no matter how well you detail and plan ahead, almost always there will be some complications or unexpected developments down the track, that will slow you down and will add to your well planned budget. Therefore it is imperative to always allow for some contingency within the budget as well as the time frame. And this is even more so the case when renovating. You never know what awaits you once you start pulling down walls, opening floors etc.

Even with this little straight forward renovation we had a few unfortunate setbacks, that did cost time and money. Originally it was planned just to replace the old dodgy power points with new ones. But when the kitchen was out the electrician advised us that the entire wiring was in a really bad condition, not up to current standards anymore and that he could not just install the power points as we wanted. We had to get the switchboard replaced as well as some of the wiring inside the walls. Which is a quite time intense and expensive job when working with massive brick walls throughout.

Also, once the old bath and the tiles came out we had to realize that the former plumber had done a really messy job, there where a lot of pipes where they didn’t belong and a lot more work involved then was anticipated.

Please check out the finished apartment under ‘Projects’

CropperCapture[176]

view from living room into kitchen

CropperCapture[177]

chalkboard wall in kitchen

CropperCapture[181]

new shower in the making

CropperCapture[180]

 

 

Apartment Renovation St Kilda

This small 2 bedroom apartment in the hear of St Kilda is getting a major face lift. New kitchen, new bathroom and a fresh splash of colorful paint including some new funky interior design features.

Stay tuned how this low budget renovation will transform the entire look and feel of the apartment.

Here some before shots.

CropperCapture[162]

Existing kitchen

CropperCapture[165]

Existing Bathroom

CropperCapture[166]

Existing bath which probably never ever saw cleaning products….

CropperCapture[164]

Living Room

CropperCapture[169]

Bedroom