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SUSTAINABILITY Insulate your home against heat loss

Outdoor Living
Insulate your home against heat loss

In the home
Andy Wilson

In my previous article, ‘Money Falling Through the Cracks’ (available on, I listed things householders could do to draught-proof their homes and cut down leakage of that precious warm air.
Given the raging financial storm that Ireland is now experiencing, there has probably never been a better time to tighten up on domestic heating costs.
Draughts are relatively easy to tackle; insulation somewhat less so.
A study carried out a few years ago by Joseph Little Architects found that a 5mm gap (less than a quarter inch) between rigid foam insulation and inner block work – a pretty typical situation – increased heat losses by over two-thirds.
A 15mm gap – something I have witnessed depressingly frequently in my work as an energy consultant – effectively renders the insulation useless.
And what’s worse, it’s near impossible to properly rectify. Often the only solution is to line the inside of the building with additional insulation – an expensive and disruptive procedure.
The insulation found in lofts also leaves much to be desired. Typically there is not enough, or it is installed patchily, or it is old and ineffective.
Modern building regulations require around 300mm (12 inches) of insulation in lofts, and this should be taken as the base line on which to assess your own home. Visit your loft and measure the depth of the insulation. Note the parts of the loft – along the edges of gables or around chimneys, for example – where insulation is absent completely, or where the existing insulation has become flattened with dust, mortar or miscellaneous household junk.
Next, get all the defective stuff into bin-liners and off to the landfill, and brush out or hoover all debris and dust.
Consider adding more timber on top of the existing joists, to provide deeper channels for insulation. Building guidelines frequently suggest draping additional insulation across joists as this cuts down thermal bridging through the timber, but in all other respects it’s completely impractical and even counterproductive – burying joists, electricity cables and water pipes under a sea of insulation, making access through the loft hazardous and rendering the loft completely useless as a storage space.
Joists can be deepened by screwing down extra timbers (typically 75mm to 150mm deep), either by screwing down from above if the screws are long enough or in from the side. It is only necessary to deepen every second joist. Next, buy sufficient rolls of quilt insulation to fill up the deepened joist channels. Look out for special offers in builder’s providers. For your own safety, wear a face mask and protective clothing when installing, and avoid working in a loft area alone.
The final touch is to lay cheap flooring over the joists. This protects the insulation, facilitates access, and turns the loft into a useful storage space.

Curtains provide valuable extra insulation over windows and doors. On average, around a quarter of heat losses from buildings are through windows or window frames so there are good energy savings to be made. The coldness emanating from windows can be assessed simply by sitting next to a large window on any cold night.
A good curtain should fit flush with windowsill or floor, and should be tight into the wall. If possible, the curtain should be two or three layers thick. Curtains should never, ever, be drawn over radiators – this is a bit like sitting in front of an open fire with all your outdoor clothes on, and expecting to feel warm!In these recessionary times, there is a lot of potential work out there for anyone handy with a sewing machine, making up insulated curtains to order.

Next time Energy saving at Christmas

Andy Wilson
can be contacted at 087 6714075 or email