For doors and windows you have a wide choice of materials. The cheapest option for hinged casement windows is self-adhesive foam strip which sticks to the rebate and compresses to form a tight seal when the window is closed.

Spring-seal excluder is a metal or plastic strip which you either pin or stick to the side of the rebate. Brush strips are suitable for any window which slides, particularly sash windows and patio doors.

If you're not planning on opening, an ill fitting window, use a clear liquid draught sealer. Coat the opening frame with soapy water, squeeze sealant into the frame to form a thick strip then shut the window to compress it. Open the window and allow the sealant to set.

Sash windows are tricky to draughtproof well. On the inside, fit nylon brush strip or spring-seal excluder to the top of the outer sash and to the bottom of the inner one. Fit spring-seal excluder to the frame sides (take the window out to do this). Seal the gap between the meeting rails with spring-seal excluder.

Doors need draughtproofing too, but as they must withstand a lot of opening and shutting, choose robust products. Fit a threshold draught excluder to the base of the door and foam strip or aluminium strips fitted with plastic seals to the sides.

Rake out the loose debris from the gap between the doorframe and the masonry and seal with a flexible exterior grade sealant or mastic. Never use putty or cement mortar.

Plastic film is the cheapest and easiest method but it's only intended for one season's insulation. Apply double-sided tape to the fixed frame and peel off the release paper. Stretch the film across the top, then the sides and bottom, and shrink it in place with a hairdryer. Trim the excess film.

Other types of secondary glazing have sophisticated frames to hold the glazing, allowing it to be either slid open or removed altogether for cleaning and ventilation. Check that the type you choose can be removed quickly in the event of a fire.

Existing cavity walls can be insulated by drilling a series of holes in the brickwork and either pumping or blowing insulation through them into the cavity. This must be carried out by a specialist firm. Old exterior walls can be treated with water-repellent. Interior walls can be insulated with plasterboard studding. Place aluminium foil behind the radiators to reflect heat back into the room.

Seal the gap between the bottom of skirting boards and the floor with quadrant beading, secured to the skirting with panel pins.

Plug any large gaps in a draughty timber floor with slithers of wood planed flush. Smaller gaps can be filled with caulk or decorators fillers. Never seal exterior ventilating bricks. Then cover the whole floor with hardboard, thick underlay and carpet.

Ensure that all exposed pipes, particularly long pipe runs are well lagged, and that the hot water cylinder has a well fitting jacket at least 80mm thick.

You will need at least 150mm of insulation between the joists - this is the level required in all new homes today. Check your existing insulation - it is likely to be only 50mm or 100mm thick, in which case it will need topping-up to the required level.

Do not lay insulation over cables as they may overheat, or under the cold water tank if it is at ceiling level, as it could freeze as a result. Ensure that all tanks are lagged with blanket insulation, a flexible plastic jacket. Insulate exposed pipes with pipe lagging or pre-formed, moulded insulation which is split along its length.