General Inspection And Maintenance Of Gutters And Downspouts
- Procedure code:
- Hspg Prepared For Nps - Sero
- Thermal And Moisture Protection
- Gutters & Downspouts
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GENERAL INSPECTION AND MAINTENANCE OF GUTTERS AND DOWNSPOUTS
A. This procedure includes guidance on inspecting and
maintaining gutters and downspouts.
B. Gutters on older structures can cause problems because they
are often integrated with the roof structure such as
built-in gutters, cornice gutters, hidden gutters and
Yankee gutters; and if not properly maintained can result in leaks into roof, cornice, or structure itself. Hung-gutter types are more common on newer structures.
C. A failed gutter often means that damage has spread;
repairs will be extensive, maybe complicated, and
probably expensive. A well-restored gutter, however,
faithfully inspected and maintained, should require no major repairs
for some years.
D. Downspouts, flashing, conductor heads, leaders, roof
drains, and scuppers are all part of the drainage system,
and should be included in the work list when maintenance
or repairs are being evaluated and scheduled for the
A. Liquid bleach:
CAUTION: DO NOT MIX AMMONIA WITH CHLORINE BLEACHES, A
POISONOUS GAS WILL RESULT! DO NOT USE BLEACH ON BIRD
B. Clean, potable water
A. Safety belt or harness
B. Ladders and scaffolding
C. Chicken ladder
D. Garden hose
E. Plumbers test plugs to fit the downspout conductor head
F. Carpenter's level
G. Mason's level
H. Chalk line
I. Shaped wooden or plastic paddle for scraping and sweeping
A. For steep roofs, inspect hanging gutters from ladders.
Do not rest ladders on sheet metal gutters. Establish
roof foot traffic regulations for inspection of built-in
B. Check for interior deterioration which might point to
gutter and/or roof problems.
C. Inspect for buildup of debris and vegetation such as moss
or lichen. Biological material excretes corrosive acids.
This is apt to occur with improper gutter sloping.
D. Check for adequate slope and drainage towards downspouts
E. Make sure all downspout connections have wire strainers
and that they are properly installed. Strainers will
block large debris and leaves that can block downspouts
and sewer lines.
F. Inspect for gutters that are split or cracked with loose,
broken, out of place, hangers, corners or slopes, or
pulling of fasteners, broken joints or seams; excessive
staining or punctures of gutter fabric.
G. Inspect joints frequently; Repair cracks immediately.
H. Look for corrosion around nails. Roof cement on gutters
may hide leaks that have not been corrected.
I. Check for deterioration of adjacent roof and soffit
areas, and behind downspouts. Look for peeling paint or
stains, or eroded mortar joints on adjacent surfaces.
J. Inspect the underside of the roof cornices. Water stains
may be evidence of ice dams.
K. Install soffit ventilators in the cornice. This helps
the cornice dry out and wards off rot after the
inevitable periodic leaks of water into the woodwork.
Ventilators have a drawback, of course, in that by
increasing air flow inside the cornice, they also add to
heat loss in winter. This can be minimized by proper
insulation of attic spaces.
L. Any gutter liners made of tin, galvanized iron, or terne
metal should be kept painted.
M. In addition to scheduled inspections, inspect after each
exposure to unusually severe weather conditions such as
strong winds, large snowfall, or long continuous rains.
N. Examine gutters as a part of the annual roof inspection
and repair defects immediately. Have a competent roofer
and plumber inspect the fabric and the joints for
defects. Small gutter leaks may force water into
concealed cornice and roof areas leading to major
O. Carry out a professional survey every five years.
P. In the Fall, check gutters and clean as necessary once a
week from the time the leaves begin to fall until they
have all fallen. Monthly inspections are recommended
during winter months to insure nothing impedes the flow
of water thereby causing an ice dam in freezing weather.
3.02 ERECTION, INSTALLATION, APPLICATION
A. Debris removal: Clean gutters of debris at least twice
a year especially if surrounded by large trees, in late
fall after all leaves have fallen; and in late spring
after all seed pods, flowers, etc. have fallen. Clogged
leaders can cause water overflow and ice build-up, and
any acidic elements at the bottom of a damp trash pile
can eat away at the metal liner.
1. Sweep debris from gutters with a wood or plastic
tool shaped to fit into radii or corners.
2. Remove and bag debris such as leaves, pine needles,
branches, nests and other litter so that the gutter
3. Where dirt or leaves lodge or normally collect in
the gutters, it is advisable to paint at yearly
4. If debris is blocking downspout, remove a lower
section and flush. Do not allow clog to be forced
into sewer or drainfield system. Realign the
gutters and downspouts.
B. Removing Biological Growth:
NOTE: ACTIVE METALS SUCH AS TIN AND COPPER DO NOT
SUPPORT BIOLOGICAL GROWTH.
1. When moss, lichen, or fungus is present, wipe or
scrape off growth. Use a shaped wooden or plastic
paddle so as not to scratch the surface of the
2. Use a 50/50 solution of liquid bleach and water to
saturate and disinfect the areas of biological
growth. Brush the disinfectant solution on the
gutters. Keep the solution from splashing to avoid
damage to other building material and nearby
3. After disinfectant treatment, scrub and rinse
4. When this type of vegetation persists, contact the
Regional Historic Preservation Officer (RHPO) for
END OF SECTION