Dwell [ Improvements ] Winterizing Your Home January 2007

by Jim Frazier
Images by Russell Byrne

The effects of winter with changes in temperature, wind, and especially water stresses our homes. Taking a few precautions now will possibly save us a lot of trouble and expense in the future.

Winter is tough on buildings, even in our relatively benign Northern California climate. The biggest problem buildings face comes from the effects of moisture penetration.

Water has been called a universal solvent because it seems that, given enough time it will dissolve anything that is soluble — and erode, corrode, or oxidize almost everything else.

All summer long the sun beats on your house’s paint and caulking. The sun’s UV rays cook and dry the materials. Paint grows brittle and blisters in sunshine. The caulking dries out, shrivels, and cracks in its channels. Then water from winter rainfalls seeps in behind the compromised protection and begins to penetrate your home, seeping into unprotected wood and behind siding.

“Doors and windows are major leak zones if they are not properly flashed,” stated Larry Shapiro, business director for Grace Residential Building Materials — a manufacturer of home weather barriers. The situation becomes aggravated when windowsills and trim around exterior doors begin leaking, thus creating messes for the homeowner. But even worse problems come from the water penetration that you don’t detect. This moisture can create dry rot in the wood framing, for example, thus compromising the building’s structural integrity.

“Leaks are the leading cause of rot and mold, which can cause major structural damage to homes and potential health problems for homeowners,” Shapiro said. The worst problem is the possibility of mold growing in the damp and secluded areas behind walls, above ceilings, and beneath floors. Mold spores can attach themselves to any cellulose-based materials, which includes wood and the paper behind dry wall. The spores multiply in wet, dark, and unventilated areas.

There are various species of mold. Black mold (Aspergillus niger) is particularly dangerous. This stuff can even be deadly. Spores may be inhaled into a person’s lungs, and there find the exact dark, calm, and moist conditions in which to grow, resulting in asthmatic-type breathing problems.

A plague of mold can overwhelm a house to the point that the cost of eradicating the unwelcome invader becomes greater than the structure’s value and the building has to be destroyed.

The roof is another area that you should take care with. Many homeowners don’t realize that shakes, shingles, and tiles are essentially decorations for the roof. The underlying roof paper maintains the seal. Besides looking nice, the roof covering’s main job is to protect this essential paper from the destructive UV effects of the sun.

Check your roof in the fall especially if you have pigeons. Pigeons can kill a roof! Their droppings are acidic and their feces can eat away the roofing paper. Then winter comes and the roof begins to leak.

The flat-pitched roofs in some of the older homes create special problems. Water stands on them longer than on a pitched roof.

Dirt, droppings, and dust can also fill gutters and clog downspouts. This is important for a house built on the expanding soil that is so common around here. When rainwater washes over the edges of clogged gutters and downspouts, there is the danger of it soaking into the soil and pooling around the foundations. The soil around the foundation of the house becomes saturated and then begins to expand with the potential of causing a great deal of trouble.

Even if you have a slab you just move the problem to the edge of the slab instead of to the edge of the house’s foundation. The soil expands and, like a hydraulic jack, can literally heave the slab off of level. We grade a house away at a 2% slope to eliminate that problem. However, in my experience almost all homeowners immediately put in landscaping that, in fact, changes the grade.

You can take a number of steps to head off trouble.

Check all the caulking
Walk around the house and examine all the areas that are sealed with caulk. Reseal any areas that are dried, cracked, or shriveled.

Scrape the area clear of all the old caulking. Make sure the area is perfectly dry and free of dust or dirt. You can buy caulking guns from any hardware store. Cut off the tip of the spout with a knife, moving the cut up or down the spout to create the width of caulk bead to match the seam.

Don’t use more caulk than required. Press the caulk solidly into the crack or corner you are filling by rubbing it with your fingertip or with a putty knife. When finished, wipe excess caulk from the area with a damp towel or rag.

Make sure to use paintable caulking. Paint won’t stick to any silicone based material.

Check the paint
The older the paint on your house the more necessary it is to monitor the quality. Paints no longer have the life expectancy that they use to have. Manufacturers have removed the lead and made other changes to meet VOC (Volatile Organic Compound) standards. The new paints are safer if your child eats paint chips but they break down easier and sooner.

Walk around the house and examine the paint particularly at critical points, such as inside corners, door jams, seams, etcetera. Scrape and sand any blistering paint. Make sure the area is perfectly dry and use touch-up paint on those areas. Also touch up places that are worn bare or peeling.

Tap a suspected area lightly with a hammer and listen for a dull instead of a solid sound. A soft sound might indicate the presence of wood that has lost its integrity. Use a screwdriver in problem areas to check for penetration. Have a carpenter or home repair specialist check out the extent of any problem area.  

Areas of dry rot must be cut out and replaced, usually by an experienced individual especially if it is a load-bearing area.

Check for Mold
A house infected by mold produces a pungent odor. It has a dry, dusty smell. You can usually find mold on or inside the walls and in corners that lack ventilation.

If your inspection reveals mold you have to hire the services of licensed mold-remediation companies. Ordinary contractors are not insured or licensed to do this work.

Check the Roof
Carefully examine the roof for loose shingles or curling, missing, or cracked shakes. Examine the flashings around pipes or chimneys.

Be sure that the valley between two intersecting roof lines is clear of obstructions. People don’t realize that these areas can become clogged and water can subsequently breach flashings. I’ve seen that situation many times.

Be especially careful with a tile roof. Don’t get up on one of these things yourself. You will crack the tiles by walking on them. Save this for a specialist.

If you have problems with a flat roof, you might need to replenish the tar on the roof. Hot mop roofing is a process that spreads molten tar over the roofing paper and then gravel is added as a topcoat. The old roofing materials have to be completely stripped. Like the other roof coverings, the main purpose of the gravel is to protect the roof from the sun.

Other Steps
Deep frosts can break pipes in sprinkler systems so turn these off at the end of the watering season. Find the shutoff valve between the main and the irrigation valves and shut the system off at this point. You can have problems with these pipes leaking underground. Wrap with insulation any exposed exterior pipes to protect these from the cold.

Most windows have weep holes for water that gathers inside the frame. Sand and dust can clog these. Make sure these are clear and can drain.

Change the furnace filters. Drain off sentiment from the water heater.

Turn the air conditioner on a couple times during the winter to lubricate the system.

If you have a fireplace hire a professional chimney sweep to clean the flues and chimney every fall.

Take these few easy steps and then enjoy the winter secure in the knowledge that you’ve taken care of the little troubles that, if left unattended, might grow into massive problems.

Happy winterizing! °