Drainage Management 2017-05-18T21:51:03+00:00

Foundation Maintenance

PREVENTATIVE MAINTENANCE FOR MAINTAINING DRY BASEMENTS AND/OR THE INTEGRITY OF FOUNDATIONS ON PREVIOUSLY UN-AFFECTED HOMES OR HOMES TO WHICH CORRECTIVE REPAIRS HAVE BEEN MADE.

FACT– Both excessively wet or extremely dry soil at foundation bearing level can cause considerable disruption to a foundations integrity.

NOTE– If the integrity of the foundation has been disrupted (ie cracks, settlement, raising, excessive moisture build up, etc.) It may still be possible to maintain a dry basement, but once a leak has occurred and a “path” established, it usually takes more technical corrective action.

Throughout 2011 we have seen a large number of failed waterlines leaking at the foundation due to dry soil conditions causing the clay to shrink and rupturing of the line. Make sure to water your foundation during the long dry spells of summer to prevent this.

Foundation Drains

In most all instances in Mid-Missouri a foundation or footing drain must exist and drain positively down to a storm drain, or to a day light. If such a drain does not exist a sump pump should be installed, on the exterior, if feasible. Contact Gary Naugle Co. for installation.

Drains for foundations must be kept open and free flowing with a rodent barrier maintained at the outlet.

Grade and Grass Cover

The surrounding grade of spaces below grade (basements, crawl spaces, etc.) and concrete slabs adjacent to such areas (porches, garages, patios, etc.) should slope 6″ within 6′, and have a tight, well maintained grass cover. The grade must continue to drain sufficiently beyond this 6′ area.

The surrounding grade of foundation walls and concrete slabs that are even with, or below the floor of the spaces mentioned above, and homes that are built wholly on a concrete slab should have a minimum slope of 4″ within 10′ and have a well maintained grass cover.

Gutter and Downspout Drains/Splash Blocks

A minimum 3′ length splash block should be installed under downspout outlets. The “spill” of this block should be onto tight grass cover or other water penetration resistant surfaces that continue on the sufficient slop to drain. This type of surface drainage is the most dependable.

Drain pipes may be extended underground, but they must be of watertight piping, be kept opened up, and should have a rodent barrier at the outlet. They should be inspected regularly for leakage at the downspout-to-pipe connection.

Landscape Planting

Landscape plantings around foundations should be avoided as much as practical, and open soil gardens are an absolute no.

If plantings exist or will be planted, the previously stated grades should be maintained. However, they may be somewhat less with a good installation of the membrane as follows:

Install a membrane consisting of a double layer of 6 mill or one layer of 10 mill poly film, from the foundation or slab to the area where a tight grass cover will be maintained. Turn the poly up on, and keep it tight to the foundation or slab, and seal any joints in the poly with mastic.

Install the plantings through the poly or install the poly around the plants. Apply bark or other mulch. If a rock mulch is to be used, apply approx. 1″ of sand or a landscape fabric before placing the rock.

If there are edgings around the mulched plantings be sure allowances are made to thoroughly drain the planting area.

Large Trees

Large trees can be, and many times are, disastrous to foundations, because of the enormous amounts of water they take in. A medium size tree (16 inch) can consume up to 50 gallons of water per day. In general, the foundation of the home should be 7′ below the base of any large trees (12″ caliper or more) that have the extreme outside edges of their branches extending over the home.

Other than ignoring the situation for the sake of the trees, the only remedy you have to assure the integrity of the foundation against the effects of the tree is to remove the tree or pier (under pin) the foundation to the required depth. Cutting back the branches will not solve the problem.

NOTE – Garage slabs, slab homes, and the walkout part of basement wall foundations normally have a bearing depth of less than 3′.

Voids at Front Porches etc.

If your home was properly built, the front porch and possibly other areas of concrete on your home are supported on “ears” that are an integral part of the foundation, or the concrete is attached to the foundation by other means.

In such cases there is normally a void or hole that appears under these slabs. The only effect this hole has is to let water get in around the foundation and the hole should be filled enough to stop water penetration.

Yard Grading For Foundation and Waterproofing Repair Work and Yard Regrades for Drainage Management

SCOPE:
These grades are guidelines and not hard and fast rules. A survey of the project should be done before work or grading starts and variances from the optimum or the minimum should be set out by, or discussed with the production department.

CLEARANCES AT:

Siding- (figure 1) clearance below siding should be 6” or more, but in cases where other existing conditions (extreme cases such as sidewalks, misc obstructions, and total lot slope, etc) will not allow the 6”, a minimum 3” would be acceptable

Brick- (figure 2) clearance below brick should be 4” or more with a minimum of 1” for extreme cases.

Note- new construction (room additions, new homes, etc) must have a 8” clearance below the siding (city code).
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SLOPE AWAY FROM HOUSE:

Below Grade Specs- (figure 3) the surrounding grade of spaces below grade (basements, crawl spaces, etc) should slope 8” or more in 6’ with a minimum of 6” in 6’ for extreme cases.

Grade Level Spaces- (figure 4) the surrounding grade of foundation walls and concrete slabs that are adjacent to the below grade space or that are at or below the floor level of the below grade space (porches, garages, walks, patios at walkout masements, etc) should be no less than 6” in 6’ with a minimum of 4” in 6’ for extreme cases.

Slope Beyond 6’– The grade beyond 6’ to 12’ out should be ½” per foot or more with a minimum or ¼” per foot in extreme cases. The grade beyond 12” should be ¼” or more per foot with a minimum or 1/8” per foot in extreme cases.
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PLANTING BED WITH MEMBRANE:

Grade- The slope on a planting bed should be 1” per foot or more with a minimum of 1/2” per foot for extreme cases.

Membrane Installation- Install a membrane consisting of a double layer of 6 mill or one layer of 10 mill poly film, from the foundation or slab to the area where a tight grass cover will be maintained. Turn the poly up on, and keep it tight to the foundation or slab, and seal any joints in the poly with mastic. Install the planting through the poly or install the poly around the plants. Apply bark or other mulch. If an angular rock mulch is to be used, apply approximately 1” or sand before placing the rock. If there are edgings around the mulched plantings, be sure openings are made to thoroughly drain the planting area.

Driveway Slope-
Gravel driveways should slop 6” from the door in the first 8’

DRAINAGE SPECIALTIES:

Splash Blocks Install a 3’ minimum length splash block at gutter downspouts.

Pipe Drains- Install pipe drains with a slope of ¼” per foot or more with a minimum of 1/8” per foot in extreme cases. Install a removable drain screen or gutter connector on the inlet and a rodent barrier screen on the outlet.

FINE GRADING AND SEEDING:

Top Soil- Spread approximately 1” of top soil over harsh and barren sub soil clays.

Fine Grade- The final grade should not be smooth, but it must be “true” with out pockets and humps. The surface may contain clods to 2” in size.

Fertilizer- Apply approximately 2 lbs of fertilizer per 100 sq ft.

Seeding- Apply approximately ¾ lbs of seed mix per 100 sq ft lightly raking into extremely smooth areas.

Mulch- Apply approximately ½ bale of, well torn apart and distributed straw per 100 sq ft.

Watering- Hose down straw enough to dampen and matt down.

Throughout 2011 we have seen a large number of failed waterlines leaking at the foundation due to dry soil conditions causing the clay to shrink and rupturing of the line. Make sure to water your foundation during the long dry spells of summer to prevent this.