Ensure a combination of adequate insulation and good ventilation

Keeping rain out of your house is key, but you also need to be careful that you’re not trapping moisture inside, writes Kya deLongschamps

Putting a wary eye over the house before winter, we’re striving to improve three areas with our available budget. Obviously we need to keep God’s elements outside — rain lashing the roof, wind borne rain working into the porous, imperfect fabric of the house, and moisture from the wet earth vaulting the protection of the DPC.

Secondly, there’s insulation — retaining heat. A house with a BER of A3 is so tightly made and well insulated it will be comfortably warmed by recycling body heat, passive solar gain and the heat thrown off appliances drawn through the mechanical ventilation with heat recovery (MVHR). Colder, older houses? Cheery sieves.

Thirdly, it’s crucial to ensure regular exchange of air from stale to fresh. Insulation and ventilation are close dance partners. The more you insulate a moisture-rich house, the more condensation will gather inside. Even if you manage to warm the place up, the mould spores and cloying atmosphere will be a skin creeping misery — unhealthy, especially for anyone in the family with respiratory problems.

Starting outside — stand well back and look up — use binoculars. Seeping, dripping, pooling moisture from slipped slates and bowed gutters can reduce indoor comfort levels, ruin interior decoration and set your house up for serious structural problems. Are there any rogue slates? Are the ridge tiles complete? If remedial work is needed, look for a reputable firm with public, employers’ and third-party insurance, VAT registration and recommendations from other customers in your area. Large holes in the fascias or soffits can invite damp and condensation into your attic. Don’t give money upfront to any trout-faced Jonah calling door to door offering to tinker with the roof — a popular autumn scam.

Taking in the rainwater system — be aware of green growth waving from the gutters or staining to the walls that could signal blockages and breaks in runs or down-pipes. Failing gutters holding pooling water against the fabric of the building, or spilling it out of cracks and breaks — the moisture can soak, settle and even freeze in cracks, damaging render. In summer black PVC guttering can get very hot. This can allow joints to spring apart.

If you live in a one-storey bungalow, a steady hand to hold the ladder, a garden trowel, rubber gloves and a hose — might be all you need. If you notice persistent drips as the centre of runs of gutter, they may require re-hanging to ensure a good fall. Small repairs to PVC guttering are doable if you can wrangle a drill, level and touch of waterproof mastic. A seasoned professional firm will give you a quick quote for cleaning gutters by phone or online (ex.repairs). Expect to pay in the area of €100 for fascias, soffits and gutters cleaned with the aid of a cherry picker in a suburban area. If you have a satellite dish, this is a good time to ensure the mounting bracket is secure. Even a small dish can be a dangerous missile.

At ground level, look for the position of your DPC — your defence against capillary action pulling water up the walls, across insulation and into interior surfaces. It should be maintained around 15cm above ground level. Clear away piles of leaves and debris that might allow moisture to ‘jump’ over the damp protection. Ensure vents running below flooring indoors, are clear without damage that could admit vermin. It’s worth looking out for these sneaky conduit points all over the external envelope. If rain is splashing back onto the walls of the house —a gravel path of 10mm shingle might be the answer.

Your greatest single protection from cold is to muffle the house with adequate insulation in the roof (see our guide) and to detail draught-proofing to every floor, door and window. Outside of major renovation works — you can do most of this yourself or with the help of a general contractor.

Seals around windows and doors should be checked individually inside and out — a breezy day is a gift. Run your fingers around the entire perimeter of the unit indoors, noting chill spots. Around edges and under sills, a gun-applied silicone sealant (touch dry in 60 seconds) is useful. Be careful with expanding foam products. They can physically push elements of windows and even doors, out of alignment.

Rubber wedge gaskets, that sit into the window between the frame and the glass outside, must be the correct profile — brings a sample with you to your supplier. Indoors, use stick-on foam strips (around 80c-€1 per linear metre), screw on brushes (from €10) and compression seals suited to the action of your doors and windows (also from €1 per linear metre). Two-piece threshold excluders are highly effective — uniting the base of the door and the floor in a tight, warm seal. From €20 per door. If you have a porch, insulate both external and interior doors to create an air-lock.

If your windows are single pane, or even double glazed but failing, try Exitex Glazing Film, finished with heavy lined curtains held to the walls with Velcro strips. Warmed with a hairdryer glazing film will seal the windows temporarily against draughts. At 4.5m² — €15.99 —Woodies DIY. Never seal trickle vents on windows. We breathe 12,000l of air a day and need that air exchange.

For old wood flooring — small 2mm-5mm gaps can be filled with a recipe of papier-mâché. Try a mixture of newspaper pulped into water and squeezed out, combined with wallpaper paste to make really thick putty. Use a flexible knife to butter this mixture into the gaps, leave to dry for at least 24 hours and sand flat. Large holes and gaps of 6mm plus can be filled permanently with softwood plugs and wedges, glued and tapped in with a wood mallet. Finish with a dense, thick rug.

DraughtEx comes on a roll and can be run into gappy boards and along skirting. Around €40 a 4mm diameter in a 40m roll, it allows for the contraction and expansion of timber flooring and in a neutral colour picks up the individual colour of the floor – very handy, shopireland.ie. The skirting area should be detailed with wooden beading and silicone sealants.

If you have a working fireplace or flue it must be swept at least once a year. Accumulating soot and debris can block the passage of smoke and/or ignite into a chimney fire. A clean flue will also increase the efficiency of your fire, stove or boiler. If you have just moved into a second-hand home, have the chimney swept regardless of what the previous owners may tell you. Expect to pay in the area of €60 for a single chimney to be power-swept. Have your CH boiler serviced whatever fuel you’re using (€100 well spent) and change the batteries on your CO and smoke alarms.

Insulation and ventilation are close dance partners. The more you insulate a moisture-rich house, the more condensation will gather inside