1: Installing a heating system can be fairly pointless if a home isn't well insulated, as a lot of your heat will go out through the roof and disappear through the walls (their construction determines just how much). In effect, insulation is like wrapping a duvet around your home - it also protects homes from excess heat in the summer (this is hardly a pressing problem in Ireland, but anyone who's been in a caravan in a continental heatwave will know how oven-like a thin-walled property can become).
2: The easiest and cheapest ways to insulate a home are in the roof space, lagging a boiler and draught-proofing windows. You can do them all yourself.
3: Types of insulation include: blanket insulation, which is made from glass-fibre, mineral fibre and rock fibre. These usually come in rolls. Loose-fill insulation comes in the form of pellets or granules which are poured into a space. It's made from various substances including mineral wool, cork granules or cellulose fibre (made from recycled paper) and comes in bags. This works well where you have irregular joists in a roof space. You can also buy rigid and semi-rigid sheet insulation.
4: Loft insulation with mineral fibre matting is rolled out to fit snugly between joists to cover the floor of the attic space. This is easy enough to do and the product is available from DIY stores or try Capco Insulation Centre. You do need to wear protective clothing, as I've learnt to my cost, or you will itch for days. Some people opt to line the slope of the roof rather than the attic floor but this will mean that you'll end up heating the roof space as well - which is fine if you're actually going to use it as a room.
5: Less common forms of insulation include cut-up newspaper (treated with a fire retardant) and wool which is arguably the best form of insulation for both walls and roofs. Once you've laid insulation on the attic floor you can cover it with boards if you need to use the attic for storage.
6: There are three ways of insulating walls - if, that is, they need insulating. Lots of traditional houses don't necessarily need insulating if they have well-built, thick walls. A traditional rubble stone wall held together with a lime, sand and mortar mix, which has a lime/sand render both outside and inside the wall, will provide good insulation. This is because the materials the wall is made from are fairly porous, are able to breathe and contain a lot of air which creates the duvet effect. The types of wall that may need insulating are very thin ones built with dense materials that harbour little air, resulting in poor insulation.
One way of insulating a wall is to fill the cavity (if the building has a double-wall construction) between the outer and inner layers (known as leaves). A substance, such as polystyrene beads or cellulose fibre, is injected into the wall from the outside to create hundreds of air pockets that hold heat in the walls. But there are differing views on the effectiveness of this form of insulation. One reason the cavity is there is to prevent damp from the outer leaf reaching the inner leaf so if a substance is put between the two it can create a bridge for the damp to cross, enabling it to get to the inner wall. "There is a greater risk of this happening in areas with high winds and driving rain - which would make it difficult in the western and northwestern seaboards and on mountain tops. A number of materials do have additives to prevent moisture penetration, though," according to Tom Halpin of the Irish Energy Centre. Ideally, your contractor will conduct a survey to see whether the wall is suitable for cavity insulation. Ask your contractor if they can provide a long-term guarantee and if they'll make good any damp problems free of charge.
Another way of insulating the walls is to put a form of plasterboard, with insulating material stuck to the back of it, on to the internal wall. However, this reduces the size of the rooms by about 4 inches on each wall. This type of insulation keeps warm air in the room from escaping but it doesn't enable the wall to be used as a heat store. Certain walls, such as stone and brick, are able to retain heat (and cold) for lengthy periods. By allowing the outside of the building to act as a thermal store you can create a more even temperature all year round, helping the house stay warm in winter and cool in summer.
By insulating the exterior of the wall you enable the wall to work as a thermal store but it will take longer to heat up whereas with internal insulation you can give the room a quick blast of heat and it will retain it. External walls are insulated by fixing the insulating material to the outer wall and covering it with a render. This is expensive and only really worth doing if you are revamping the exterior anyway (or building from scratch!) Because you've expanded the exterior wall you may need to adjust the eaves and downpipes and you may need planning permission.
7: When choosing insulation materials, be aware of their effect on the environment and on your own health - you don't want to live among warm toxic fumes. Wool is an excellent insulator and is also environmentally friendly; cellulose - recycled newspaper - can also be pumped into a space. These still aren't widely available here and may have to be imported.
8: Basic window insulators are curtains and shutters. The most cost-effective way of saving heat loss at windows is through weather stripping and these products can be bought in DIY stores - the cheaper ones, such as self-adhesive foam, will need replacing fairly frequently, but it's easy enough to do. In terms of heating costs, draught sealing will pay for itself within months. But be careful not to shut off the air supply. In the past homes were ventilated through their fireplace and chimneys but centrally heated homes which are completely sealed are prone to damp and the build-up of chemicals, such as formaldehyde, from furnishing and building products.
9: Hot Water cylinder jackets pay for themselves very quickly and can be bought in DIY shops. If you're at the building stage then it will be worth insulating hot water pipes beneath floors as well.
10: If you take up the ground floor for any reason, perhaps to put in a damp-proof course, take the opportunity to put insulation under the floor as well but it's not really worth doing if you aren't renovating the floor anyway as the disruption is huge. One simple form of insulation is to put carpets on the floor!
11: If you're insulating a wall or roof you need to be consistent and insulate the entire area. Heat will rush out through any uninsulated areas, known as cold bridges, causing condensation, which will lead to damp patches.
12: The 1997 building regulations have specified minimum insulation values which all new buildings have to comply with but it still may pay you to insulate, as much as you can, beyond these levels.
13: Exterior insulation costs around £55 to £70 (€70 to €89) a square metre (depending on the finish you choose), which equates to around £5,500 (€7,000) for the average house. Dry lining internally costs around £20 to £25 (€25 to €32) a square metre. Cavity wall insulation costs between £4 and £7 (€5 to €9) a square metre and attic insulation costs about £2 to £5 (€2.54 to (€6.35) a square metre. High specification draught proofing costs between £3 and £5 (€4 to €6.35) a square metre.
