Secondary Glazing

October 30, 2008

Secondary glazing provides an excellent alternative to double glazing in cases where replacing the existing windows is not possible due to preservation orders, though as the seal is not as tight as double glazing, the reduction in heat loss through the window is not as much.

The idea is this, a second pane of glass on a light frame is attached to the inside of the existing frame. This second pane reduces heat loss in two ways. Firstly if creates a barrier between the warm inside air and the cold outside air, reducing convection losses. Secondly it traps a layer of air between two panes, reducing heat loss through conduction.

In cases where the window must be open-able, secondary glazing products are available which allow for this requirement. Options such as horizontal sliders, vertical sliders, and hinged units are available. Magnetic, clip on and screw on units which can be installed during colder months are a cheaper and more robust solution.


Curtains – the best value for money energy saver

October 28, 2008

Curtains can reduce heat loss in the winter by 10% – 25% and reduce drafts significantly. So considering their relatively low cost, and other benefits, are a very good investment. They do this by providing a barrier between the window, and the main room. In general windows have the poorest U-Values in an average room, and so are the focus of most heat loss during colder times. Warm air circulates around the space due to convection and is suddenly cooled when it touches the relatively cold windows. Curtains act as a barrier to this air flow, and so reduce the amount of air being cooled.

Here are some tips to help you save energy with your curtains:

  • Actually use the your curtains when you have them available
  • The more completely the curtains cover the window the better, so have large ones with plenty of overlap and overhang at the ends
  • Lining in curtains reduce air infiltration through them, and so is well worth the investment
  • Curtains should be hung as close to the window as possible to reduce air leaking in from the side.
  • The longer the curtains the better.
  • Install a cornice at the top of a curtain
  • Use Velco to attach the ends of the curtains to the walls and to each other in the centre
  • Blinds do little to reduce heat loss in the winter

The power of the sun

October 25, 2008

Draft proofing hinged windows and doors

October 22, 2008

When draft proofing  hinged type of windows or doors, similar principles can be used for the sides and the top of doors as with the top and bottom of sash windows. First you need some compressive foam seals, or in some cases a roll of soft polystyrene can be a cheaper solution. With the door or window open, these are fitted to the frame on the top and sides of the door or window, along with the bottom of the window frame. When doing this it is important that you cut the strip to the exact size required to provide as tight a seal as possible.

With regards to external doors, the base of the door is often the worst source of drafts following poor installation and years of wear and tear. The solution is a bristle strip, cut to the correct length and attached securely to the base of the door.

In some cases, where very large gaps are present, it may be necessary to install an aluminium strip to provide an even surface which can be used form a tight seal.


Finally, with regards to doors mail boxes and key holes are a source of drafts, and should be fitted with appropriate covers.

Have you Weatherized you house?

October 19, 2008

Weatherization, what a great word. It refers to protecting a building from the elements, or for the purpose of this blog, the particular elements of wind, snow, cold and rain. I’m particularly interested in things you can do to improve energy efficiency and comfort. Anyway, here is a bit of a list

  • Air sealing cracks, gaps, holes around doors, windows, and in walls
  • Block up and insulate gaps around pipes that penetrate the attic ceiling, and other areas with high potential for heat loss.
  • Protecting pipes from corrosion and freezing.
  • Installing drains, foundation waterproofing membranes, downspout extensions, downward-sloping grading, French drains, etc to prevent water flowing under doors or lodging beside walls
  • Insuring that roofing, building wrap (walls), siding, flashing etc can prevent wind, rain or snow from getting in (depending on how much is possible for your area)
  • Have enough insulation to reduce heat losses to an acceptable level
  • Providing proper ventilation to unconditioned spaces to protect a building from the effects of condensation.

Ireland introduces a bicycle tax relief

October 16, 2008

An updated version of this post with all the information you are probably looking for can be found here


In what was generally regarded as a tough budget yesterday, Ireland introduced a Tax relief for workers to buy a bike. I’m really for this. The nay-sayers are having a field day saying that it always rains, or that few people are in a position to cycle, but small steps make big differences. If 100,000 more people in Ireland cycle, just one day a week, that would be a great success. Also it would have great benefits to the congestion, and health.


Anyway… enough editorial, here are the details

From 1 January 2009, the provision of bicycles and associated safety equipment by employers to employees who agree to use the bicycles to cycle to work will be treated as a tax exempt benefit-in-kind. The exemption may only apply once in any five year period in respect of any employee and the limit is €1,000

Draft-proofing sash windows

October 13, 2008

The two materials you will need are bristles strips, and compressive foam seals.


First open the window. Put compressive foam seals on the underside of the top and bottom edge of the window (Marked A). When doing this it is important that you cut the strip to the exact size required to provide as complete a seal as possible. For wider frames it may be possible to install a second layer of compressive frame seal.

Next, close the window, and fit bristle strip to both sides of the beading of the lower sash (Marked B). Do exactly the same for the upper sash BUT on the outside.

Finally to draft proof where the sashs meet (Marked C). Bristle strips should be fitter on both sides with the bristles facing each other just touching. This will stop drafts coming in the middle.