Roof Insulation

You put a hat on your head and keep your body heat in. Thermal insulation in your roof will do the same for your house.

If you do not have insulation in your roof, up to 30% of your heat could escape, costing you money and contributing to atmospheric pollution and global warming.

If you have already insulated your roof, you may want to replace it or add another layer to improve its performance and bring it up to current Building Regulations Standards. (more…)

When old man winter comes knocking at our door,  as he most certainly has today, I start to think about keepping warm.  Inevitably, I want that to be as cost effective as possible but also as environmentally friendly as possible.  Thankfully staying warm and green on those long, winter nights without seeing your monthly bills skyrocket as the temperature falls in not out of the question.

A good place to start is checking for drafts coming from the doors and windows. Look to see if the caulking or weather stripping is damaged. If it is damaged or even destroyed, replace it immediately.

When replacing old weather stripping or caulking, it is important to remove it thoroughly before placing the new materials onto your windows and doors.

Another good tip for preventing drafts from your windows is to hang thick curtains, preferably lined ones.  Draw the curtains closed during the evening and night hours. Open them to the warmth of the sun during the daytime hours.

Additionally, you can also invest in a draft excluder for the bottom of your door to prevent drafts from entering your home. Ideally, you should follow this strategy at night when the air is typically at its coldest and the draft excluder will be less of an inconvenience.

If ther draft is really bad you may consider replacing old, outdated windows and doors. Replacing energy-inefficient windows and doors with energy-efficient windows and doors will save on heating costs. Plus, they should not require annual bouts of caulking and weather stripping.

Although this type of home improvement can be expensive, most home improvement stores offer sales throughout the year – with the downturn in construction there are some really good deals to be made at the moment. In addition, discontinued styles are often sold at cost or close to cost just so the manufacturer can make room for new merchandise. This type of home improvement can raise the market value of your home, while also lowering your utility bills at the same time.

Another money-saving strategy for the winter is to purchase and install programmable thermostats in each room where it is possible to do so. Programmable thermostats can help to reduce the cost of heating your home. They can be set to lower the temperature during the times throughout the day and evening when you do not need the heat. This strategy saves on energy use and cost.

Another money-saving strategy is to replace your incandescent bulbs with compact fluorescent bulbs. If you simply cannot do away with all of your incandescent bulbs, replace the ones that you can afford to replace. Fluorescent bulbs use less energy, and this fact can be particularly important in the winter months when lights are needed more frequently.

Finally, if at any time you intend to replace any of your appliances, purchase replacements that feature the Energy Star® logo. They really do use less energy and save you money in the process. During peak periods of winter energy use, you will be glad that you replaced your old, outdated hot water heater, furnace, or oven with an energy-efficient model.

It is important to follow as many of the above strategies as you can in order to exercise winter energy conservation. After all, what is the point of staying indoors if you can’t snuggle up?

source: www.eco-wisdom.com

Guide to Wall Insulation

Up to half of the heat loss from a house occurs through the walls. This can be reduced by two-thirds by insulating the walls.

Most houses built before about 1980 have no wall insulation. Many (though not all) houses built during the 1980s have some wall insulation. Houses built since the 1991 Building Regulations came into effect are required to have wall insulation.

Insulation may be placed on the outside, in the cavity or on the inside of a wall, without altering the overall insulation properties.

When considering wall insulation, first you should find out whether your house has cavity walls or solid walls. A  building contractor, BER Assessor or architect will be able to tell you if you have cavity walls in your new or older house.

Cavity wall insulation

The walls of many houses consist of two ‘leaves’ of brick or concrete block with a cavity or space between them to resist rain penetration.

In older houses insulation can be injected into this cavity through holes drilled through the outer leaf, by means of a blowing or pumping machine.

Since the work is done from outside, it cause minimum disturbances inside. The drilled holes, which are typically about 25mm (1 inch) in diameter and spaced a metre or so apart, are then filled to match the wall appearance as closely as possible. The job typically takes less than a day.

In relation to the pumping of your walls with a bonded bead system you would noticeably improve the overall thermal properties of your house and in turn reduce your energy bills for the winter months.

Suitability of Cavity Insulation

It is important before deciding to insulate existing cavity walls that you check their suitability for cavity insulation. This assessment will take account of the degree of exposure of the house to wind-driven rain and the construction details and condition of the walls. Any ventilation openings in the wall will also be checked to ensure that these will not be blocked by the insulation.

There are a number of issues you should be aware when filling your wall’s cavity:

If there were any frost or structural damage to any of the house’s external walls pumping of beads into the cavity would not be advised.

The width of the cavity between your external wall leaf and the installed aero-board should be at least 50mm.
 

If there is any problem with dampness in the internal leaf it would not be recommended to add the beads to the cavity as they would only increase the path for water to travel into the wall.

If the wall suffers from rain penetration at times, this problem must be remedied first.

In some cases, the walls may be found to be unsuitable for cavity insulation or may require some remedial work beforehand.

Savings

The cost of cavity wall insulation depends on a number of factors, including the width of the cavity, but it is typically in the region of €5 to €7 per square metre. For a typical semi-detached house, this gives a total cost of about €550-€700. With annual fuel savings of €200 to €320, the payback period will be in the region of 4 to 7 years.

You may be able to negotiate a lower price if you can persuade some of your neighbours to have their walls insulated at the same time.

I intend over the next few weeks to explain all the main elements of passive house, from triple glazed windows, through heat recovery ventilation, airtightness and so forth. I would like firstly to explain what exactly a passive house is, however, so here goes.
Firstly, I need to clarify that the term passive house is perhaps a little misleading because you might have the wrong impression that it concerns only ‘houses’, but that couldn’t be further from the truth. I have visited a range of passive house projects across Europe, including passive house schools, passive house offices, passive house community centres, passive house churches and, believe it or not, even a passive house fire station. So, you can build pretty much anything to the ‘passive house standard’ (including a passive house house, by the way!). 

The next common urban myth about passive houses is that you have to follow a very strict design style in order to achieve the required standard. Week in week out we receive planning permissions drawings from people who want to test their house design to see if it can achieve the passive house standard. We’ve seen all sorts of shapes, sizes and orientations and the vast majority of them, with enough insulation, high quality glazing and good airtightness can pretty easily achieve the required standard. So, the passive house standard is not as limiting as many people assume in terms of building design.

Next, I need to emphasise that the passive house is not magic. You’ll read from time to time that passive houses are buildings that don’t need heating, but that is simply not true. All buildings in a climate even as mild as Ireland need some form of heating – even if it is a tiny fraction compared to a conventional building. As a example, my demonstration home, ‘Out of the Blue’, in Wicklow, uses just 10% of the heating energy compared to a conventional house, but it does need that 10%. So a passive house is not a zero-heating house, but a building that needs a very small back-up heating system and without the need for radiators or underfloor heating.

At a more technical level, there are three criteria that must be achieved in order to reach the passive house standard, as follows:
- Maximum annual space heating demand per square metre of 15 kWh
- Minimum airtightness of 0.6 air changes per hour measured at a pressure of 50 Pascal
- Maximum annual primary energy demand per square metre (for all electrical use, even white goods) of 120 kWh

So I would conclude that the passive house standard is a method of design and construction that delivers a building with a very low heating energy demand. Nothing more, nothing less. I will be giving a step by step guide on the main elements of the passive house over the next few weeks, so stand by.

What’s a green building?  One covered in solar panels and bristling with turbines?  One that proclaims its greenness by looking different?  One that costs 15% more than a ‘conventional’ building?

For British architect Howard Liddell, the answer is none of the above.

At a one-day symposium on sustainability in TCD recently, Liddell outlined his ideal green building: it looks conventional, costs no more to build, but is so well insulated and airtight that there is almost no need for heating, and certainly no need for what he calls “eco-bling”.

The main problem, as he sees it, is that technologies are an expensive add-on with a long payback time.  The sensible and cost-effective route to a green and eco-building is effective insulation.

Unfortunately, eco-bling is flavour of the month, and Liddell was particularly critical of new building regulations in some British local authorities that now require a minimum 10% of on-site renewable technologies — expensive and ineffective wind turbines on top of buildings, when they should be on remote, windy sites.

In an inspiring presentation, Liddell,  principal architect with the British-based Gaia Group, argued that we need to make insulation sexy. “Eco-minimalism, not eco-bling.”

Effective insulation alone, he said, could halve the energy demand, and significantly reduce fuel poverty.

The main challenge, in Ireland as in Britain, will be to retro-fit a high standard of insulation to existing buildings. What’s more, each building will need an individual solution.

And you can’t just fill cavity walls with foam, he argues: those walls were designed to breathe so, if you block them up, you simply create a moisture problem on the inside.

Likewise, it is not enough to seal every crack with gunge.  For a start, the gunge will crack, so you won’t get an airtight seal. And again, you have to worry about moisture buffering.

Other issues that he identified are: effective testing of a building’s air tightness; and indoor air quality in an airtight building (especially moisture content, and off-gassing from materials and furniture), making choice of materials essential.

To be truly ‘green’, he recommended using sheep’s wool insulation, as he felt there were issues with the chemicals used to treat insulation made from recycled newspaper.

In a wide ranging and fascinating talk, Liddell also recommended: mass-timber construction (not just beautiful to work with, but also good for sequestering carbon dioxide); ‘nail-free building’ (securing well designed, well fitting pieces with just a few screws), which doesn’t damage the wood and makes repairs and alterations, and recycling much easier; and low-flush toilets that use less than 2 litres of water — already achieved on aircraft toilets.

If Liddell is right, and every building leaves a customised solution, then on the plus side this would be a major job creation project architects, and the insulation and construction industries.

For more on Howard Liddell’s eco-minimalist architecture, check out his new book here.

Mary Mulvihill’s new guide to easy, sustainable living is Drive Like a Woman, Shop Like a Man (2009).  Click here to suggest a tip, and be in with a chance to win a copy of the book.

(c) Mary Mulvihill 2009  http://marymulvihill.net/

The average Irish home is falling far short of the desired BER energy efficiency rating.

Energy ratings are graded on a sliding scale: A1 is awarded to the most energy efficient homes, while G is given to the worst.  With most houses in Ireland scoring E1, the Home Energy Saving scheme, which provides grants for insulating homes is now available.

The €50 million Energy Saving scheme is open to houses built before 2006 and will help homeowners save up to €700 a year
Home improvement measures will include:

Terms and Conditions:

• Be sure that prior to applying you have read and understand the scheme’s Terms and Conditions (to be published once the scheme is open for homeowner applications) and in particular please note the following:- 
•  Grant Approval must be in place prior to any purchase of materials or commencement of measures undertaken.
•  You may apply several times, however the grant value of your first application must be €500.
•  The BER assessment grant cannot form part of the €500 amount. 
•  All works must be carried out by a contractor registered with Sustainable Energy Ireland for this particular scheme.

To find a BER assessor in your area log onto the GreenMe Directory

Anyone interested in increasing their BER rating may register their “Expression of Interest” by calling 1850 927 000 or by visiting www.sei.ie/hes

A recent email from my friend in New Zealand raised the old question of: What is the best wall for a building in terms of energy efficiency and environmental conservation?

Green Wall Types

Many solutions have been tried and many more are still being tested. People around the world have experimented with natural wall materials ranging from peat, sods, straw bales, logs, vegetation, rammed earth, hand-made bricks of various types (including dung), rubble & lime mortar, etc. Recycled man-made materials have also been used including tyres, bottles (plastic or glass), plastic crates, etc. You get the picture – for every ′solution′ there are dozens, if not hundreds, of variations.

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A modern version of the typical ′block-built′ wall system uses insulating blocks which are manufactured using aerated concrete, pumice, ash and other lightweight aggregates.

Insulating concrete is a different form of construction that has appeared over the years in various guises. Recent forms of this building method use an insulating mould or shuttering system for walls and normal concrete is poured into this to form the load-bearing part of the wall. A less well-known type of cast insulating concrete was tried in the USA after WWII.

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