Insulation keeps a house cool in summer and warm in winter; and the investment will eventually pay its way in saved energy. Here are some important pointers for installing roof insulation.
- As you put more insulation into your roof space, you will have to heave yourself from the ladder through the ceiling hatch. Securing a stout rope to the rafter directly above the hatch and grab the rope firmly to give yourself a hand and to make this part of the job easier. Add a couple of knots to the rope for a good grip.
- Dust is the enemy of reflective foil insulation. Once the shiny surface is obscured it loses its effectiveness. Clean it to restore its insulating properties, or replace it.
- Before laying insulation, look for holes around wires, pipes and air ducts through which air could flow beneath the insulation. Plug these holes with an injection of fireproof sealant or expanding foam.
- Aluminum foil laminate is an important component in domestic insulation systems as it helps to deflect heat away from the house. Tack this material to the underside of your rafters. If your foil laminate has only one shiny side, make sure the shiny side faces towards the sky.
- If your insulated roof space is unvented, keep a space between the fibreglass batts or blankets and the eaves with proprietary plastic ventilator trays fitted between the joists. Without ventilation, warm moist air rising from the house will condense in the roof space and settle as moisture causing mold and mildew.
- A well-insulated roof can cause the warm air in a house to collect in upstairs rooms. Keep them from overheating with adequate ventilation and adjustable heating.
- Use a broom to push fibreglass batts under the eaves where headroom is limited. Wear protective gear and don't tear the insulation or place it over soffit vents.
- It's the air trapped in the tiny spaces within the insulating material that provides the insulation. Compress your insulation too much and it will be much less effective.
- Keep insulation at least 25 centimetres(10 inches) clear of flues, chimneys (particularly metal chimneys from open fires) and heat-producing electrical fixtures, such as recessed lights, fans and transformers.
- Tack a board or a sheet-metal shield between the joists on each side of a fixture or fit a purpose-made shield to contain loose fill material.
For extra help installing roof vents, here is a handy how to guide.
