by Perry525 »
Wed Oct 27, 2010 10:50 am
May I say that my wife and daughters are all good at DIY, it can be cars, bikes, homes whatever....you are not alone.
The thing with insulation is that you are trying to save money on heating!
Therefore, the smaller the space to heat, the lower the cost.
From which you can see that letting your expensive heat go up into the loft, is a waste of heat, unless you live up there.
The problem? Heat always moves to cold.
Most people think that laying a bit of insulation between the joists is all that is required.
They don't seen to realise that wood, joists are not a very good insulator by today's standards, they were years ago compared to bricks and single glazed windows, now they drain your heat.
The heat loss is mainly by conduction = heat the room, the air, the ceiling, joists, rafters, roof, slates/tiles, floor boards in loft, sky, all these are joined together.
The best way to insulate is as close to the warm air in the room as possible. That means below the ceiling. Fixing two or three inch thick sheets of polystyrene below/across the ceiling, keep the heat in the room.
It stops that loss by conduction, heating so many parts of the home and sky.
I have a bedroom with 5 inches of insulation, 3 inches between the joists and 2 inches below the joists.
To put this into perspective, last winter night 3-4/1/2010 it got down to minus 28C on my lawn with an air temperature of minus 8.1C.
That bedroom never went below 20.3C with no heating, other than that from the hall outside, (the bedroom door was open,) that is kept at 22C 24/7.
On the 25.6.2010 when it got up to 44.6C outside, the bedroom stayed at 23C.
Lever up the floor boards, if nailed. You may be lucky, they may be screwed down.
Carefully fit sheets of polystyrene between the joists, making them as tight a fit as possible and fill the whole space.
If you buy one inch thick sheets they are easy to cut with a sharp knife, thicker sheets cut with a hand saw.
To make it easy, buy an electric resistance cutter, this will slice through polystyrene like a hot knife through butter. These are expensive but make the job quicker and cleaner. They are used in hand crafts to make polystyrene models.