Water, water, water, it should be listed all ten times. It is the number one reason for damage / wear noted in homes. Follow the water, it will show you potential issues.
Starting with the roof, it’s designed is to shed water off the home. So and bi- annual review certainly is in order, before and after winter months. Look for missing, damaged shingles, valley wear, all flashing, and organic debris on the roof, have it cleaned and or repaired as needed. Long term slow leaks can cause severe damage if gone undetected. Standing water only needs 48 hours and the right conditions to incubate mold growth. See diagram –https://www.nachi.org/gallery/images/exterior/general/rain.jpg
2) Water disposition, gutters / downspouts-
Water, now the roof has been reviewed and maintained, we should follow the water, how is it being disposition-ed around the home? I advise all my clients to walk around their home during a heavy rain storm with a raincoat / umbrella to see where all the water is being disposition ed from the roof surface. Once off the roof it should be discarded out and away from the foundation.
Checking and maintaining gutters, downspouts and below grade drains is paramount. Not maintaining these items can make water related issues worse than if there was no system at all and can cause significant damage to the foundation and other components. Clean gutters, watch the water flow inside the gutter to ensure proper pitch and termination into the downspouts.
When water is discharging from the down spout is should be well out and away from the foundation, using splash blocks as / if needed. Many times during a home inspection I see downspouts terminate right at the foundation, now we have collected all the roof water and funneled it back at the foundation to cause issues, not the intent of a gutter system.
Defects – https://www.nachi.org/gallery/images/indoor_air_quality/mold/gutter-defects.jpg
Downspouts – https://www.nachi.org/gallery/images/roofing/gutters_and_downspouts/downspout-extension.jpg
3) Underground perimeter foundation drains and or gutter system subsurface drains-
If subsurface drains are present, (some folks do not even know they are present) they must be reviewed and maintained annually. Footing drains, if working properly control water as it seeps in near the home’s footing, hence it helps controls the water table around the home. If these lines become plugged with sediment and or other debris the water now has no release point and the water table rises. When the water table rises around the foundation you may get water in the basement that has never been there before. Find open/ day-lighted drain pipe to ensure water runs out of it in spring thaw months. If it is not running it should be scope with a camera and or cleaned out by a line clearing company (Roto Router / septic companies). Below grade drainage systems –https://www.nachi.org/gallery/images/foundation/moisture/foundation-drainage.jpg
4) Sump pumps (if present)-
Most sump pumps and pits I see during the inspection process are installed poorly that result in poor results. Most are just below the basement surface, they should be down 18-24″ or deeper to help lower the water table under the slab or floor. They should be in a plastic or clay liner with a cover so water is not evaporating through the home. The pumps should be outfitted with a back flow preventer to stop the double pumping of the same water as it comes back into the pit, extending the pump’s service life span. Again, once the water is pumped out it needed to be out and away from the home. Sump pump – http://www.paragonstl.com/wp-content/uploads/2014/08/sump-pump-anatomy.jpg
5) Grading around the home-
Grade around the home should be positive (sloping away) about 1/4″ per foot if possible. Grade should not be closer than 6″ to the siding. Many homes have built up landscaping materials, bark mulch, stone etc. over many years that do not allow for a positive grade. Remove, regrade, and add soils as needed to reach the objective of keeping the water flowing away from the home. Water intrusion into the basement will eventual evaporate through the entire home. This can cause dampness and decreased comfort levels in the home. If enough moisture is present it can actually cause l mold growth in the attic.
Grading – https://www.nachi.org/gallery/images/foundation/moisture/surface-drainage.jpg
6) Reviewing the foundation-
The foundation should be reviewed for cracks annually to prevent water intrusion during freeze thaw cycles, where water enters the crack during the day and freezes up in the evening causing expansion in the cracks making it bigger, causing avoidable damage.
7) Vegetation around the home-
Many older homes have overgrown vegetation growing near the home that can be very damaging to the home. Vegetation should be kept at a minimum 12″ from the home, bushed, vines, trees etc. Trees should not overhang the roof within 10″ above. Trimming and or removal is needed in some cases. Air and sunlight if blocked will not allow for these areas to be dried. Vegetation left unchecked causes dampness (water again) on siding, trim, windows, masonry etc. that leads to decay or degradation of these materials. Air and sunlight is needed to keep these areas dry.
8) Sealing the siding / trim and deck areas-
All homes need to be sealed, stained, painted etc. to keep water repelling on the surface. Once exposed wood is present, water enters and starts the decay process, Mother Nature taking over. The sunny siding of the home can become sun-bleached, causing cracks, loosened nails and a weathered board look. North or shaded sides cause develop moss /mildew. Keeping up with outside siding / trim is quite important.
9) Maintaining laundry area-
Dryer vents should be clean as needed and ducts should be made of smooth wall steel, not foil or vinyl accordion type of ducting which can trap lint and cause dryer fires. Washing machine hoses should be reviewed annually and replaced when needed. Many homes have incurred major damage from washer hoses that have burst when the owner were away, if this happens hundreds of gallons of water can be dump into a home in short period of time. Water supply to washers should be shut off when not in use to put the pressure back onto the water supply lines that likely are copper and or Pex. These supply lines are rated for much greater psi than the washer hoses.
10) Not having and energy audit performed-
I recommend all homeowners unless already possessing an Energy Star home, have a thermal audit performed preferably with an infrared camera. Efficiency Vermont has pre-qualified Energy Star / BPI contractors listed on their website. If you have ice dams on your home, you should certainly consider a thermal audit. Using heat cables (if present) to remove ice dams is masking the issue of heat loss and is using more energy to get rid of a problem that likely can be solved by air sealing. Air flow – https://www.nachi.org/gallery/images/insulation_and_energy/general/blower-door.jpg
The certainly there are many more items to maintain in the home, but if the mindset is fixated on water / moisture prevention it likely will have a very positive affect on the home, short and long term.