(A) Cold weather concrete practice: The I.C.C. Council and the American Concrete Institute ACI-318 have established thresholds for placement of concrete when cold weather conditions exist. The following information is from various excerpts of the applicable code sections as they apply to the placement of concrete in cold weather conditions.
(1) Footings.
(a) Footings can be poured when the temperature is 20 degrees Fahrenheit or above, however the following precautions must be adhered to: When temperature falls below 40 degrees Fahrenheit, ACI-318 cold weather requirements shall be followed.
(b) Concrete shall be maintained at a temperature of not less than 50 degrees Fahrenheit for a minimum of three consecutive days after placement of concrete.
(c) Insulated blankets must protect the concrete and forms left in place during the three day period.
(d) The excavation shall not be left open for more than 24 hours. Protection must be provided to keep soil from freezing with insulated blankets.
(2) Foundation walls.
(a) Foundation walls may be poured when the temperature is 40 degrees Fahrenheit or above. When temperature falls below 40 degrees Fahrenheit, ACI-318 cold weather requirements shall be followed.
(b) Concrete shall be maintained at a temperature of not less than 50 degrees Fahrenheit for a minimum of seven consecutive days.
(c) Insulated blankets shall completely cover and be securely fastened to both sides and the forms must be left in place for a period of no less than three days. ACI-318
(3) Flatwork.
(a) After the first frost, it is the discretion of the Building Official if flat work can continue. Flat work is allowed if the temperature of the concrete is maintained at 50 degrees for seven consecutive days after concrete placement.
(b) The use of salamanders, or other equipment that exhaust flue gases into the area above
concrete floors must be avoided, because of the danger of carbonation to the fresh concrete.
(c) The I.C.C. Code Council and American Concrete Institute ACI-318 provides for alternates for the above. High early strength may be used to substitute the following guidelines. An increase in the amount of cement to a minimum of a six-bag mix and maintaining the concrete at 50 degrees for three consecutive days provides an option for the builders. Additionally, admixtures for high early strength may be added in accordance with the manufactures requirements.
(d) The use of visqueen and straw are not an acceptable means of protection, insulated blankets only.
(e) Please contact the Building Department prior to scheduling concrete.
(B) Drain tile shall be installed around the outside of the foundation adjacent to the footings where encompassing any below grade space. Drain tile shall be connected to a sump pump, which shall discharge into an approved drainage facility or to a point a minimum of ten feet away from the structure and must not cause a nuisance. Drain tile shall be installed between porch areas and basements/crawl spaces, between garages and basements/crawl spaces and between basements and crawl spaces. As a general rule where the area needs dampproofing it needs drain tile run to the sump pump. With the prior approval of the Building Official, drain tile may be "day-lighted" if existing contours allow.
(C) In no case shall footing drains and/or sump pumps be connected to any sanitary sewer system, or septic system.
(D) Rebar shall be provided to connect existing concrete and new concrete together. Where the bottom of the footing for the new structure does not extend to the bottom of the footing for the existing structure a minimum of 6 - #4 rebars shall be installed. Two of which are required in the bottom half of the footing depth (if a footing is proposed as part of the design).
(E) Bottom of footings/foundations for all structures shall be not less than three feet, six inches below finished grade. Minimum size of footings shall be 10" x 20" with standard "keyway", or as approved by the building official.
Exception 1: Where placed on verified solid bed rock
Exception 2: Accessory structures 1,000 square feet or less.
(F) Postholes for decks shall be a minimum of ten inches in diameter and shall extend a minimum of three feet, six inches below finished grade. Postholes shall be sized to carry the loads applied.
Exception #1: Decks can be installed on an existing slab as long as the point loads are less than 750 pounds and the slab is in good condition.
Exception #2: Postholes supporting smaller loads may be allowed to be 8" in diameter around pools and for stair support (entire post must rest on concrete).
(G) Foundation shall be backfilled with clean fill. Do not use debris for backfilling.
(H) All column footings supporting beams must bear centrally on a minimum 36" x 36" square x 12" deep concrete column footing or a continuous strip footing with at least 2 - #4 rebars 12" thick x 24" wide. Rivet, weld or bolt top of steel column to steel girders (or lag screw to wood girders) and anchor bottom by bolts or embed in concrete (on interior of structures). Column footings shall be protected from frost where exposed to the exterior environment.
Exception 1: Columns supported by exterior foundation walls that have horizontal rebar in order to spread out the load.
Exception 2: Smaller column footings may be allowed for smaller loads not associated with the main support beams of the home and for structures other than single family residences, duplex's and townhouses.
(I) All structures shall be required to provide a minimum of four inch thick concrete floor slab. All slabs shall have a minimum of four-inch compacted stone base.
Exception 1: Accessory structures less than 200 sq. ft.
Exception 2: Pole barn construction on one acre parcels or larger provided a 4" stone floor is installed.
Exception 3: Decks
Exception 4: Three season rooms that can show at least 12" of air flow below the structure provided a 6 mil vapor barrier is installed and 4" of pea gravel.
Exception 5: Buildings used for agricultural needs.
Exception 6: Greenhouses.
Exception 7: Crawl spaces with a minimum 2" slush coat of concrete and 4" of stone.
(J) Concrete landings for single family homes, townhouses and duplex's and stairs adjacent to doors of structures shall have wing walls with at least #4 rebar within 3" to 6" from each end and every 2' on center.
Exception: Concrete landings that have foundation walls on all sides surrounding the landing.
(K) All new detached structures 201 square feet to 1,000 square feet that do not extend down to the frost line shall have an 18" deep (12" below finished grade and 6" above) by 12" wide thickened edge. Porches and any other areas shall be included in the square footage.
Exception: Additions to existing accessory structures shall be taken on a case by case basis once existing conditions are determined.
(L) The minimum trench foundation wall thickness shall be 12" in width and extend 42" below grade. Trench foundations shall be allowed for slab on grade construction only.
(M) Wood foundations below grade are prohibited.
Exception: Pole Barn Construction.
(N) The minimum concrete or masonry foundation wall must have an eight inch nominal thickness, minimum foundation wall thickness, 12 inches for trench foundation.
(O) When concrete cannot be placed on undisturbed virgin ground concrete shall be placed only on clean compacted fill (compacted to 95% Proctor density) stone fill or virgin clay free from any vegetation, debris, or organic soils.
Exception: The portion of an addition adjacent to an existing foundation with rebar doweled into existing foundation (see section (D) of this section)
(P) All commercial/industrial structural pier drawings shall be designed, sealed, signed, and dated by a registered design professional.
(Q) Foundation walls with an unsupported length greater than 50 feet and a height greater than 4' but less than 8' shall have a minimum of 1 - #4 vertical rebar at 24" on center for 8" walls and 1 - #4 vertical rebar at 30" on center for 10" walls with rebar placed within 1 1/4" to 2" of the inside face of the wall.
(R) Openings in foundation wall for windows shall have at least 1 - #4 rebar on all 4 sides within 12" of the window frame.
(S) The support of a building shall extend around the entire building.
Exception: Postholes designed to carry the loads applied.
(T) Ten inch wide concrete foundation walls with an unsupported length less than 20' shall not require vertical rebar if 9' or less in height as long as 2 - #4 rebar are installed at top, middle and bottom where the floor diaphragm is attached to the sill plate on top of the foundation wall.
(U) Eight inch wide concrete foundation walls with an unsupported length less than 15' shall not require vertical rebar if 8' or less in height as long as 2 - #4 rebar are installed at top, middle and bottom.
(V) The minimum concrete slab thickness shall not be less than 4". The minimum amount of stone below the concrete slabs shall not be less than 4". Piping of any kind shall not run horizontally inside the slab depth.
Exception: Piping is allowed to run in the slab where structural concrete supports such as footings prohibit running the piping below the slab.
(W) Each plate section attached to a foundation shall have at least 2 code compliant anchor bolts.
(X) Window wells shall have stone and drains at least 2" below the window run to a sump pump.
(Y) Foam sill sealer shall be required below all sill plates attached to foundations.
(Z) Structures shall not be allowed to have some sections capable of moving with frost and other sections protected from frost (foundation insulation can be added to protect shallow portion).
(AA) Structures that require a permit shall have concrete support.
Exception 1: Sheds less than 200 square feet.
Exception 2: Structures where a structural engineer from the State of Illinois has designed an alternative and all manufacturer and research report requirements have been met.
(BB) Structures built under the International Residential Code (IRC) will only be required to submit a soil test if questionable soils are encountered during excavation as determined by the building inspector. It is recommended that areas near a designated flood plain or wetland area perform soil testing.
(Ord. 14-103, passed 5-15-2014; Am. Ord. 21-102, passed 8-19-21) Penalty, see § 150.999